Bryant 987MA Installation, Start-up, Operating And Service And Maintenance Instructions

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Page 1

987MA MODULATING 4--WAY MULTIPOISE GAS FURNACE SERIES A .

Installation, Start--up, Operating and

Service and Maintenance Instructions

NOTE: Read the entire instruction manual before starting the

installation.

SAFETY CONSIDERATIONS 3.........................

INTRODUCTION 4...................................

CODES AND STANDARDS 4...........................

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS 4...

ACCESSORIES 5.....................................

LOCATION 5........................................

AIR FOR COMBUSTION AND VENTILATION 9..........

CONDENSATE TRAP 11...............................

Upflow 11........................................

Downflow 11.....................................

Horizontal 11......................................

CONDENSATE DRAIN 16.............................

INSTALLATION 18...................................

Upflow 18........................................

Downflow 18.....................................

Horizontal 19......................................

Filter Arrangement 19...............................

AIR DUCTS 26.......................................

Ductwork Acoustical Treatment 26.....................

GAS PIPING 29......................................

ELECTRICAL CONNECTIONS 30.......................

115--V Wiring 30...................................

J--Box Installation 31................................

24--V Wiring 31....................................

Accessories 31.....................................

Alternate Power Supplies 32..........................

VENTING 38........................................

Special Venting Requirements for Installations in Canada 38.

Materials 39.......................................

Venting Systems 39.................................

Locating Vent Termination 39.........................

Size the Vent and Combustion Air Pipes 40...............

Combustion Air and Vent Piping Insulation Guidelines 40...

Configure the Furnace 40............................

Installing the Vent Termination 41......................

Venting System Length Calculations 44.................

START--UP, ADJUSTMENT, AND SAFETY CHECK 57......

Select Setup Switch Positions 57........................

Prime Condensate Trap 57.............................

Purge Gas Lines 57...................................

Adjustments 58......................................

Check Safety Controls 60..............................

Checklist 61........................................

SERVICE AND MAINTENANCE PROCEDURES 67........

Cleaning Heat Exchangers 72...........................

SEQUENCE OF OPERATION 79........................

PARTS REPLACEMENT GUIDE 84......................

TABLES

Loose Parts Bag Contents 6..............................

Minimum Clearances to Combustible Materials 6.............

Minimum Free Area Required 10.........................

Minimum Space Volumes 10.............................

Filter Size Information 20...............................

Opening Dimensions 22................................

Air Delivery CFM 27...................................

Maximum Capacity of Pipe 30...........................

Electrical Data 32......................................

Vent Termination Kit for Direct Vent (2--Pipe) Systems 39......

Combustion--Air Vent Pipe, Fitting & Cement Material.. 42.....

Maximum Allowable Exposed Vent Lengths Insulation 43......

Maximum Equivalent Vent Length 44......................

Deductions from Maximum Equivalent Vent Length 44........

Altitude Derate Multiplier for U.S.A. 64....................

Blower Off Delay Setup Switch 64........................

Gas Rate 64..........................................

Orifice Size and Manifold Pressure 65.....................

Always Ask For

CERTIFIED

Use of the AHRI Certified TM Mark indicates a manufacturer’s participation in the program. For verification of certification for individual products, go to www.ahridirectory.org.

Portions of the text and tables are reprinted from NFPA 54/ANSI Z223.1--2009E, with permission of National Fire Protection Association, Quincy, MA 02269 and American Gas Association, Washington DC 20001. This reprinted material is not the complete and official position of the NFPA or ANSI on the referenced subject, which is represented only by the standard in its entirety.

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987MA

Required Notice for Massachusetts Installations

IMPORTANT

The Commonwealth of Massachusetts requires compliance with regulation 248 CMR as follows:

5.08: Modifications to NFPA--54, Chapter 10

2) Revise 10.8.3 by adding the following additional requirements: a. For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in

whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting, including but not limited to decks and porches, the following requirements shall be satisfied:

1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall horizontal vented gas fueled equipment, the installing plumber or gasfitter shall observe that a hard wired carbon monoxide detector with an alarm and battery back--up is installed on the floor level where the gas equipment is to be installed. In addition, the installing plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling, building or structure served by the side wall horizontal vented gas fueled equipment. It shall be the responsibility of the property owner to secure the services of qualified licensed professionals for the installation of hard wired carbon monoxide detectors

a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the hard wired

carbon monoxide detector with alarm and battery back--up may be installed on the next adjacent floor level.

b. In the event that the requirements of this subdivision can not be met at the timeof completion of installation, the owner shall

have a period of thirty (30) days to comply with the aboverequirements; provided, however, that during said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall be installed.

2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in accordance with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.

3. SIGNAGE. A metal or plastic identification plate shall be permanently mounted to the exterior of the building at a minimum height of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled heating appliance or equipment. The sign shall read, in print size no less than one--half (1/2) inch in size, ”GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.

4. INSPECTION. The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4.

5. EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:

(1.) The equipment listed in Chapter 10 entitled ”Equipment Not Required To Be Vented” in the most current edition of

NFPA 54 as adopted by the Board; and

(2.) Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate from

the dwelling, building or structure used in whole or in part for residential purposes.

c. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM PROVIDED. When the

manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design or venting system components with the equipment, the instructions provided by the manufacturer for installation of the equipment and the venting system shall include:

1. Detailed instructions for the installation of the venting system design or the venting system components; and

2. A complete parts list for the venting system design or venting system.

d. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED. When

the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does not provide the parts for venting the flue gases, but identifies “special venting systems”, the following requirements shall be satisfied by the manufacturer:

1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation instructions; and

2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a parts list and detailed installation instructions.

e. A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment,

all venting instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain with the appliance or equipment at the completion of the installation.

For questions regarding these requirements, please contact the Commonwealth of Massachusetts Board of State Examiners of Plumbers and

Gas Fitters, 239 Causeway Street, Boston, MA 02114. 617--727--9952.

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SAFETY CONSIDERATIONS

WARNING

FIRE, EXPLOSION, ELECTRICAL SHOCK, AND CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous operation, personal injury, death, or property damage.

Improper installation, adjustment, alteration, service, maintenance, or use can cause carbon monoxide poisoning, explosion, fire, electrical shock, or other conditions which may cause personal injury or property damage. Consult a qualified service agency, local gas supplier, or your distributor or branch for information or assistance. The qualified service agency must use only factory--authorized and listed kits or accessories when modifying this product.

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component damage.

Application of this furnace should be indoors with special attention given to vent sizing and material, gas input rate, air temperature rise, unit leveling, and unit sizing.

Improper installation, adjustment, alteration, service, maintenance, or use can cause explosion, fire, electrical shock, or other conditions which may cause death, personal injury, or property damage. Consult a qualified installer, service agency, or your distributor or branch for information or assistance. The qualified installer or agency must use factory-authorized kits or accessories when modifying this product. Refer to the individual instructions packaged with the kits or accessories when installing.

Installing and servicing heating equipment can be hazardous due to gas and electrical components. Only trained and qualified

personnel should install, repair, or service heating equipment.

Untrained personnel can perform basic maintenance functions such as cleaning and replacing air filters. All other operations must be performed by trained service personnel. When working on heating equipment, observe precautions in literature, on tags, and on labels attached to or shipped with furnace and other safety precautions that may apply.

These instructions cover minimum requirements and conform to existing national standards and safety codes. In some instances, these instructions exceed certain local codes and ordinances, especially those that may not have kept up with changing residential construction practices. We require these instructions as a minimum for a safe installation.

Follow all safety codes. Wear safety glasses, protective clothing, and work gloves. Have a fire extinguisher available. Read these instructions thoroughly and follow all warnings or cautions included in literature and attached to the unit.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care

and wear appropriate protective clothing, safety glasses and gloves when handling parts, and servicing furnaces.

This is the safety--alert symbol . When you see this symbol on the furnace and in instructions or manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING,and

CAUTION. These words are used with the safety--alert symbol. DANGER identifies the most serious hazards which will result in

severe personal injury or death. WARNING signifies a hazard which could result in personal injury or death. CAUTION is used to identify hazards which may result in minor personal injury or product and property damage. NOTE is used to highlight suggestions which will result in enhanced installation, reliability, or operation.

1. Use only with type of gas approved for this furnace. Refer to the furnace rating plate.

2. Install this furnace only in a location and position as specified in the “Location” section of these instructions.

3. Provide adequate combustion and ventilation air to the furnace space as specified in “Air for Combustion and Ventilation” section.

4. Combustion products must be discharged outdoors. Connect this furnace to an approved vent system only, as specified in the “Venting” section of these instructions.

5. Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically for the detection of leaks to check all connections, as specified in the “Gas Piping” section.

6. Always install furnace to operate within the furnace’s intended temperature--rise range with a duct system which has an external static pressure within the allowable range, as specified in the “Start--Up, Adjustments, and Safety Check” section. See furnace rating plate.

7. When a furnace is installed so that supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air shall also be handled by duct(s) sealed to the furnace casing and terminating outside the space containing the furnace. See “Air Ducts” section.

8. A gas--fired furnace for installation in a residential garage must be installed as specified in the warning box in the “Location” section.

9. The furnacemay be used for construction heat provided that the furnace installation and operation complies with the first CAUTION in the LOCATION section of these instructions.

10. These Multipoise Gas--Fired Furnaces are CSA design--certified for use with natural and propane gases (see furnace rating plate) and for installation in alcoves, attics, basements, closets, utility rooms, crawlspaces, and garages. The furnace is factory--shipped for use with natural gas. A CSA (A.G.A. and C.G.A.) listed accessory gas conversion kit is required to convert furnace for use with propane gas.

11. See Table 2 for required clearances to combustible construction.

12. Maintain a 1--in. (25 mm) clearance from combustible materials to supply air ductwork for a distance of 36 in. (914 mm) horizontally from the furnace. See NFPA 90B or local code for further requirements.

13. These furnaces SHALL NOT be installed directly on carpeting, tile, or any other combustible material other than wood flooring. In downflow installations, factory accessory floor base MUST be used when installed on combustible materials and wood flooring. Special base is not required when this furnace is installed on manufacturer’s Coil Assembly Part No. CNRV, CNPV, CAP, or CAR or when Coil Box Part No. KCAKC is used. See Table 2 for clearance to combustible construction information.

987MA

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INTRODUCTION

This 4--way multipoise Category IV condensing furnace is CSA design--certified as a direct (2-pipe) or non-direct vent (1-pipe) furnace. (See Fig. 2.)The furnace is factory--shipped for use with natural gas. The furnace can be converted in the field for use with propane gas when a factory-supplied conversion kit is used. Refer to the furnace rating plate for conversion kit information.

This furnace is not approved for installation in mobile homes, recreational vehicles, or outdoors.

This furnace is designed for minimum continuous return--air temperature of 60_F(15_C) db or intermittent operation down to 55_F(13_C) db such as when used with a night setback thermostat. Return-air temperature must not exceed 80_F(27_C) db. Failure to follow these return-air temperature limits may affect reliability of heat exchangers, motors, and controls. (See Fig. 3).

The furnace should be sized to provide 100 percent of the design heating load requirement plus any margin that occurs because of furnace model size capacity increments. Heating load estimates can be made using approved methods available from Air Conditioning Contractors of America (Manual J); American Society of Heating,

987MA

Refrigerating, and Air--Conditioning Engineers; or other approved engineering methods. Excessive oversizing of the furnace could cause the furnace and/or vent to fail prematurely.

For accessory installation details, refer to the applicable instruction literature.

NOTE: Remove all shipping materials, loose parts bag, and literature before operating the furnace. (See Table 1).

CODES AND STANDARDS

Follow all national and local codes and standards in addition to these instructions. The installation must comply with

regulations of the serving gas supplier, local building, heating, plumbing, and other codes. In absence of local codes, the installation must comply with the national codes listed below and all authorities having jurisdiction.

In the United States and Canada, follow all codes and standards for the following:

Safety

S US: National Fuel Gas Code (NFGC) NFPA 54--2009/ANSI

Z223.1--2009 and the Installation Standards, Warm Air Heating and Air Conditioning Systems ANSI/NFPA 90B

S CANADA: National Standard of Canada, Natural Gas and

Propane Installation Code (NSCNGPIC) CAN/CSA B149.1--2010

General Installation

S US: NFGC and the NFPA 90B. For copies, contact the National

Fire Protection Association Inc., Batterymarch Park, Quincy, MA 02269; or for only the NFGC contact the American Gas Association, 400 N. Capitol, N.W., Washington DC 20001

S CANADA: NSCNGPIC. For a copy, contact Standard Sales,

CSA International, 178 Rexdale Boulevard, Etobicoke (Toronto), Ontario, M9W 1R3, Canada

Combustion and Ventilation Air

S US: Section 9.3 of the NFPA54/ANSI Z223.1--2009 Air for

Combustion and Ventilation

S CANADA: Part 8 of the CAN/CSA B149.1--2010, Venting

Systems and Air Supply for Appliances

Duct Systems

S US and CANADA: Air Conditioning Contractors Association

(ACCA) Manual D, Sheet Metal and Air Conditioning Contractors National Association (SMACNA), or American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) 2005 Fundamentals Handbook Chapter 35

Acoustical Lining and Fibrous Glass Duct

S US and CANADA: current edition of SMACNA, NFPA 90B as

tested by UL Standard 181 for Class I Rigid Air Ducts

Gas Piping and Gas Pipe Pressure Testing

S US: NFPA 54/ANSI Z223.1--2009 NFGC; Chapters 5, 6, 7, and 8

and national plumbing codes. CANADA: CAN/CSA--B149.1--2010, Parts 4, 5, 6, and 9.

In the state of Massachusetts:

S This product must be installed by a licensed plumber or gas fitter. S When flexible connectors are used, the maximum length shall

not exceed 36 in. (914 mm).

S When lever type gas shutoffs are used they shall be T--handle type. S The use of copper tubing for gas piping is not approved by the

state of Massachusetts.

Electrical Connections

S US: National Electrical Code (NEC) ANSI/NFPA 70--2011 S CANADA: Canadian Electrical Code CSA C22.1

ELECTROSTATIC DISCHARGE (ESD)

PRECAUTIONS PROCEDURE

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component damage.

Electrostatic discharge can affect electronic components. Take precautions during furnace installation and servicing to protect the furnace electronic control. Precautions will prevent electrostatic discharges from personnel and hand tools which are held during the procedure. These precautions will help to avoid exposing the control to electrostatic discharge by putting the furnace, the control, and the person at the same electrostatic potential.

1. Disconnect all power to the furnace. Multiple disconnects

may be required. DO NOT TOUCH THE CONTROL

OR ANY WIRE CONNECTED TO THE CONTROL PRIOR TO DISCHARGING YOUR BODY’S ELECTROSTATIC CHARGE TO GROUND.

2. Firmly touch the clean, unpainted, metal surface of the furnace chassis which is close to the control. Tools held in a person’s hand during grounding will be satisfactorily discharged.

3. After touching the chassis, you may proceed to service the control or connecting wires as long as you do nothing to recharge your body with static electricity (for example; DO NOT move or shuffle your feet, do not touch ungrounded objects, etc.).

4. If you touch ungrounded objects (and recharge your body with static electricity), firmly touch a clean, unpainted metal surface of the furnace again before touching control or wires.

5. Use this procedure for installed and uninstalled (ungrounded) furnaces.

6. Before removing a new control from its container, discharge your body’s electrostatic charge to ground to protect the control from damage. If the control is to be installed in a furnace, follow items 1 through 4 before bringing the control or yourself in contact with the furnace. Put all used and new controls into containers before touching ungrounded objects.

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7. An ESD service kit (available from commercial sources) mayalsobeusedtopreventESDdamage.

ACCESSORIES

See Product Data Sheet for a list of accessories for this product

LOCATION

CAUTION

PERSONAL INJURY AND/OR PROPERTY DAMAGE HAZARD

Improper use or installation of this furnace may result in premature furnace component failure. This gas furnace may be used for heating buildings under construction provided that:

--The furnace is permanently installed with all electrical wiring, piping, venting and ducting installed according to these installation instructions. A return air duct is provided, sealed to the furnace casing, and terminated outside the space containing the furnace. This prevents a negative pressure condition as created by the circulating air blower, causing a flame rollout and/or drawing combustion products into the structure.

--The furnace is controlled by a thermostat. It may not be “hot wired” to provide heat continuously to the structure without thermostatic control.

--Clean outside air is provided for combustion. This is to minimize the corrosive effects of adhesives, sealers and other construction materials. It also prevents the entrainment of drywall dust into combustion air, which can cause fouling and plugging of furnace components.

--The temperature of the return air to the furnace is maintained between 55_F(13_C) and 80_F(27_C), with no evening setback or shutdown. The use of the furnace while the structure is under construction is deemed to be intermittent operation per our installation instructions.

--The air temperature rise is within the rated rise range on the furnace rating plate, and the gas input rate has been set to the nameplate value.

--The filters used to clean the circulating air during the construction process must be either changed or thoroughly cleaned prior to occupancy.

--The furnace, ductwork and filters are cleaned as necessary to remove drywall dust and construction debris from all HVAC system components after construction is completed.

--Verify proper furnace operating conditions including ignition, gas input rate, air temperature rise, and venting according to these installation instructions.

General

These furnaces are shipped with the following materials to assist in proper furnace installation. These materials are shipped in the main blower compartment. See Table 1 for loose parts bag contents.

This furnace must:

S be installed so the electrical components are protected from

water.

S not be installed directly on any combustible material other than

wood flooring (refer to SAFETY CONSIDERATIONS).

S be located close to the chimney or vent and attached to an air

distribution system. Refer to Air Ducts section.

S be provided ample space for servicing and cleaning. Always

comply with minimum fire protection clearances shown in Table 2 or on the furnace clearance to combustible construction label.

WARNING

CARBON MONOXIDE POISONING / COMPONENT DAMAGE HAZARD

Failure to follow this warning could result in personal injury or death and unit component damage.

Corrosive or contaminated air may cause failure of parts containing flue gas, which could leak into the living space. Air for combustion must not be contaminated by halogen compounds, which include fluoride, chloride, bromide, and iodide. These elements can corrode heat exchangers and shorten furnace life. Air contaminants are found in aerosol sprays, detergents, bleaches, cleaning solvents, salts, air fresheners, and other household products. Do not install furnace in a corrosive or contaminated atmosphere. Make sure all combustion and circulating air requirements are met, in addition to all local codes and ordinances.

The following types of furnace installations may require OUTDOOR AIR for combustion due to chemical exposures:

S Commercial buildings S Buildings with indoor pools S Laundry rooms S Hobby or craft rooms S Chemical storage areas

If air is exposed to the following substances, it should not be used for combustion air, and outdoor air may be required for combustion:

S Permanent wave solutions S Chlorinated waxes and cleaners S Chlorine based swimming pool chemicals S Water softening chemicals S De--icing salts or chemicals S Carbon tetrachloride S Halogen type refrigerants S Cleaning solvents (such as perchloroethylene) S Printing inks, paint removers, varnishes, etc. S Hydrochloric acid S Cements and glues S Antistatic fabric softeners for clothes dryers S Masonry acid washing materials

All fuel--burning equipment must be supplied with air for fuel combustion. Sufficient air must be provided to avoid negative pressure in the equipment room or space. A positive seal must be made between the furnace cabinet and the return--air duct to prevent pulling air from the burner area.

987MA

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WARNING

987MA

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

When the furnace is installed in a residential garage, the burners and ignition sources must be located at least 18 in. (457 mm) above the floor. The furnace must be located or protected to avoid damage by vehicles. When the furnace is installed in a public garage, airplane hangar, or other building having a hazardous atmosphere, the furnace must be installed in accordance with the NFPA 54/ANSI Z223.1--2009 or CAN/CSA B149.2--2010. (See Fig. 5.)

Table 1 – Loose Parts Bag Contents (Provided in blower compartment)

DESCRIPTION QUANTITY

AirIntakePipeFlange 1

Vent Pipe Flange 1

Coupling Flange Gaskets 2

Sharp Tip Screws (Vent and Inlet Flanges) 10

Vent Pipe Coupling 1

Vent Pipe Coupling Clamps 2

Pressure Switch Tube 1

Outlet Choke Plate (used with 40k BTUH furnaces, only) 1

Drain Tube Elbow 1

Drain Extension Tube 1

Drain Tube Clamps 2

Drain Line Grommet 1

Gas Line Grommet 1

Gas Line Knockout Plug 1

Junction Box Cover 1

Junction Box Base 1

Green Ground Screw 1

Blunt Tip Screws (Junction Box) 3

Thermostat Wire Grommet 1

FIRE HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

Do not install the furnace on its back or hang furnace with control compartment facing downward. Safety control operation will be adversely affected. Never connect return--air ducts to the back of the furnace. (See Fig. 4.)

Location Relative to Cooling Equipment

The cooling coil must be installed parallel with, or on the downstream side of the unit to avoid condensation in the heat exchangers. When installed parallel with the furnace, dampers or other flow control must prevent chilled air from entering the furnace. If the dampers are manually operated, they must be equipped with means to prevent operation of either unit unless the damper is in the full--heat or full--cool position.

Table 2 – Minimum Clearances to Combustible Materials for All Units

POSITION CLEARANCE

Rear 0(0mm)

Front (Combustion air openings in furnace and in structure) 1in.(25mm)

Required for service *24 in. (610 mm)

All Sides of Supply Plenum 1in.(25mm)

Sides 0(0mm)

Vent 0(0mm)

Top of Furnace 1in. (25mm)

* Recommended

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29 1/2

[749.3]

28 3/4

[730.5]

[678.1]

26 11/16

26 3/8

[370.0]

22 7/16

[670.0]

21 1/16

[535.8]

AIR FLOW

[76.2]

1 3/4

[44.5]

AIR INTAKE

7/8

GAS CONN

[22.2]

7/8

[22.2]

THERMOSTAT ENTRY

[76.2 ]

7/8

[22.2]

7/8

[22.2] POWER CONN

28 3/8

[773.7]

30 7/16

[889.0]

SIDE INLET

7/8

17 7/16

[720.4]

28 5/8

[22.2]

[442.3]

[609.7]

[726.9]

[420.9]

16 9/16

20 1/4

[513.9]

[25.4]

11/16

23 3/8

1 5/16

[17.5]

[592.0]

[33.3]

[668.8]

26 5/16

SD5024-4

NONE

PART NUMBER

NEXT SHEET

987MA

6 15/16

[176.1]

2 3/10

[58.4]

987MA

042060

VENT

[76.2]

042080

060100

066120

[76.2]

AIR INTAKE

[170.1]

6 11/16

[678.1]

26 11/16

26 3/8

[670.0]

25 1/8

[638.7]

23 5/16

[592.9]

19 1/8

[485.8]

OUTLET WIDTH

[76.2]

AIR INTAKE

AIR FLOW

5/8

[15.8]

1 3/4

AIR FLOW

[44.5]

GAS CONN

[76.2]

VENT

7/8

[22.2]

CONDENSATE DRAIN TRAP

LOCATION

32 5/8

28 3/16

7/8

[22.2] POWER CONN

7/8

[22.2]

THERMOSTAT ENTRY

[829.5]

[715.9]

28 5/8

[726.4]

7/8

SIDE INLET

25 3/16

20 1/4

[22.2]

[639.1]

[513.9]

16 9/16

[581.9]

22 15/16

17 5/16

[420.9]

14 13/16

[439.2]

[376.3]

WIDTH

BOTTOM RETURN

11/16

[17.5]

[558.3]

[25.4]

of1sideandthebottom,orthebottomonlyreturnairopeningsmayberequiredforairflowrequirementsabove1800CFMat0.5in.W.C.E.S.P.

c. For 1600 CFM ---22 --- in. (559 mm) round or 14 1/2 x 22 1/16--- in. (368 x 560mm) rectangle.

a. For 800 CFM---16 ---in. (406 mm) round or 14 1/2 x 12---i n. (368 x 305 mm) rectangle.

b. For 1200 CFM--- 20--- in. (508 mm) round or 14 1/2 x 19 1/2---i n. (368 x 495 mm) rectangle.

d. For airflow requirements above 1800 CFM, see Air Delivery table in these installation instructions for specific use of single side inlets. The use of both side inlets, a combination

NOTE: Doors may vary by model.

[668.8]

26 5/16

[534.0]

A11522

Fig. 1 -- Dimensional Drawing

Page 8

THE BLOWER IS LOCATED

TO THE RIGHT OF THE

BURNER SECTION, AND

AIR CONDITIONED AIR IS

DISCHARGED TO THE LEFT.

THE BLOWER IS

LOCATED BELOW THE

BURNER SECTION, AND

CONDITIONED AIR IS

DISCHARGED UPWARD.

987MA

THE BLOWER IS

LOCATED ABOVE THE

BURNER SECTION, AND

CONDITIONED AIR IS

DISCHARGED DOWNWARD

Fig. 2 -- Multipoise Orientations

SUPPLY AIR

Fig. 3 -- Freeze Protection and Return Air Temperature

THE BLOWER IS

LOCATED TO THE LEFT

OF THE BURNER SECTION,

AND CONDITIONED AIR IS

DISCHARGED TO THE RIGHT.

A02097

80 / 27˚C

/ 16˚C

A10490

Fig. 4 -- Prohibited Installations

A10494

18-IN. (457.2 mm)

MINIMUM TO BURNERS

A93044

Fig. 5 -- Installation in a Garage

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AIR FOR COMBUSTION AND

VENTILATION

Introduction

Direct Vent (2--pipe) Applications

When the furnace is installed as a direct vent (2-pipe) furnace, no special provisions for air for combustion are required. However, other gas appliances installed in the space with the furnace may require outside air for combustion. Follow the guidelines below to insure that other gas appliances have sufficient air for combustion.

Ventilated Combustion Air Applications

When the furnace is installed using the ventilated combustion air option, the attic or crawlspace must freely communicate with the outdoor to provide sufficient air for combustion. The combustion air pipe cannot be terminated in attics or crawlspaces that use ventilation fans designed to operate during the heating season. If ventilation fans are present in these areas, the combustion air pipe must terminate outdoors as a Direct Vent/ 2-Pipe system.

All air for combustion is piped directly to the furnace from a space that is well ventilated with outdoor air (such as an attic or crawl space) and the space is well isolated from the living space or garage. In addition, other gas appliances installed in the space with the furnace may require outside air for combustion. Follow the guidelines below to insure that the roof or crawlspace walls have sufficient free area to provide sufficient air for combustion and ventilation for the furnaces. The guidelines below can be used to insure that other gas appliances have sufficient air for combustion.

Provisions for adequate combustion, ventilation, and dilution air must be provided in accordance with:

S U.S.A. Installations: Section 9.3 of the NFPA 54/ANSI

Z223.1--2009 , Air for Combustion and Ventilation and applicable provisions of the local building codes.

S Canada: Part 8 of the CAN/CSA--B149.1--2010, Venting

Systems and Air Supply for Appliances.

Outdoor Combustion Air Method

1. Provide the space with sufficient air for proper combustion, ventilation, and dilution of flue gases using permanent horizontal or vertical duct(s) or opening(s) directly communicating with the outdoors or spaces that freely communicate with the outdoors.

2. Fig. 6 illustrates how to provide TWO OUTDOOR OPENINGS, one inlet and one outlet combustion and ventilation air opening, to the outdoors.

a. One opening MUST commence within 12 in. (300 mm)

of the ceiling and the second opening MUST commence within 12 in. (300 mm) of the floor.

b. Size openings and ducts per Fig. 6 and Table 3.

c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq.

mm) of free areaper 2,000 Btuh (1,100mm binedinput for allgasappliances in thespaceper Fig. 6and Tab le 3 .

d. TWO OPENINGS OR VERTICAL DUCTS require 1

sq. in. (645 sq. mm) of free area per 4,000 Btuh (550

/kW) for combined input of all gas appliances in the

mm space per Fig. 6 and Table 3.

3. ONE OUTDOOR OPENING requires:

a. 1 sq. in. (645 sq. mm) of free area per 3,000 Btuh (734

/kW) for combined input of all gas appliances in the

mm space per Fig. 6 and Table 3.

b. Not less than thesum of the areas ofall vent connectors in

the space.

The opening shall commence within 12 in. (300 mm) of the ceiling. Appliances in the space shall have clearances of at least 1 in. (25 mm) from the sides and back and 6 in. (150 mm) from the front. The opening shall directly communicate with the outdoors or shall communicate through a vertical or horizontal duct to the outdoors or spaces (crawl or attic) that freely communicate with the outdoors.

/kW) of com-

987MA

CAUTION

FURNACE CORROSION HAZARD

Failure to follow this caution may result in furnace damage. Air for combustion must not be contaminated by halogen

compounds, which include fluoride, chloride, bromide, and iodide. These elements can corrode heat exchangers and shorten furnace life. Air contaminants are found in aerosol sprays, detergents, bleaches, cleaning solvents, salts, air fresheners, and other household products.

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

The operation of exhaust fans, kitchen ventilation fans, clothes dryers, attic exhaust fans or fireplaces could create a NEGATIVE PRESSURE CONDITION at the furnace. Make--up air MUST be provided for the ventilation devices, in addition to that required by the furnace. Refer to the Carbon Monoxide Poisoning Hazard warning in the venting section of these instructions to determine if an adequate amount ofmake--up air isavailable.

Page 10

Table 3 – Minimum Free Area Required for Each Combustion AirOpening or Duct to Outdoors

TWO HORIZONTAL DUCTS

FURNACE

INPUT

(BTUH)

40,000*

60,000

80,000 100,000 120,000

140,000*

*Not all families have these models.

(1 SQ. IN./2,000 BTUH)

(1,100 SQ. MM/KW)

Free Area of

Opening and D uct

Sq. In (Sq. mm)

20 (12904) 5 (127) 14 (8696) 5 (127) 10 (6452) 4 (102)

30 (19355) 6 (152) 20 (13043) 5 (127) 15 (9678) 5 (127)

40 (25807) 7 (178) 27 (17391) 6 (152) 20 (12904) 5 (127)

50 (32258) 8 (203) 34 (21739) 7 (178) 25 (16130) 6 (152)

60 (38709) 9 (229) 40 (26087) 7 (178) 30 (19355) 6 (152)

70 (45161) 10 (254) 47 ( 30435) 8 (203) 35 (22581) 7 (178)

Round Duct

In. (mm) Dia

FURNACE WATER HEATER TOTAL INPUT

100,000 + 30,000 = (130,000 divided by 4,000) = 32.5 Sq. In. for each two Vertical Ducts or Openings

60,000 + 40,000 = (100,000 divided by 3,000) = 33.3 Sq. In. for each Single Duct or Opening

80,000 + 30,000 = (110,000 divided by 2,000) = 55.0 Sq. In. for each two Horizontal Ducts

Table 4 – Minimum Space Volumes for 100% Combustion, Ventilation and Dilution Air from Outdoors

987MA

OTHER THAN FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

ACH

0.60

0.50

0.40

0.30

0.20

0.10

0.00

NP = Not Permitted

30 40 50 40 60 80 100 120 140

1,050 (29.7)

1,260 (35.6)

1,575 (44.5)

2,100 (59.4)

3,150 (89.1)

6,300

(178.0)

NP NP NP NP NP NP NP NP NP

1,400 (39.6)

1,680 (47.5)

2,100 (59.4)

2,800 (79.2)

4,200

(118.9)

8,400

(237.8)

1,750

(49.5)

2,100 (59.4)

2,625 (74.3)

3,500 (99.1)

5,250

(148.6)

10,500

(297.3)

SINGLE DUCT OR OPENING

(1 SQ. IN./3,000 BTUH)

(734 SQ. MM/KW)

Free Area of

Opening and D uct

Sq. In (Sq. mm)

Round Duct

In. (mm) Dia

EXAMPLES: Determining Free Area

FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

SpaceVolumeFt3(M3)

1,400 (39.6)

1,680 (47.5)

2,100 (59.4)

2,800 (79.2)

4,200

(118.9)

8,400

(237.8)

DUCTS

OUTDOORS

1,500 (42.5)

1,800 (51.0)

2,250 (63.7)

3,000 (84.9)

4,500

(127.3)

9,000

(254.6)

1 SQ IN. PER 4000 BTUH*

2,000 (56.6)

2,400 (67.9)

3,000 (84.9)

4,000

(113.2)

6,000

(169.8)

12,000 (339.5)

TWO OPENINGS OR

VERTICAL DUCTS

(1 SQ. IN./4,000 BTUH)

Free Area of Open-

2,500 (70.8)

3,000 (84.9)

3,750

(106.1)

5,000

(141.5)

7,500

(212.2)

15,000 (424.4)

(550 SQ. MM/KW)

ing and Duct

Sq. In ( mm)

(101.9)

(127.3)

(169.8)

(254.6)

18,000 (509.2)

3,000 (84.9)

3,600

4,500

6,000

9,000

Round Duct

In. (mm) Dia.

3,500 (99.1)

4,200

(118.9)

5,250

(148.6)

7,000

(198.1)

10,500

(297.1)

21,000

(594.1)

(305mm)

12″ MAX

1 SQ IN. PER 2000 BTUH*

DUCTS

OUTDOORS

1 SQ IN. PER 2000 BTUH*

(305mm)

12″ MAX

CIRCULATING AIR DUCTS

NOTE: Use any of the following combinations of openings:

AIR DUCTS

CIRCULATING

*Minimum dimensions of 3---in. (76 mm).

OF COMBUSTION AIR

CLEARANCE IN FRONT

A&BC&DD&EF&G

VENT THROUGH ROOF

(76mm)

AT LEAST 3 IN.

OPENINGS SHALL BE

OUTDOORS

DUCT

12″ MAX

(305mm)

1 SQ IN.

1 SQ IN. PER 4000 BTUH*

12″ MAX

PER 4000

BTUH*

OUTDOORS

PER 4000

BTUH*

12″ MAX

(305mm)

Fig. 6 -- Air for Combustion, Ventilation, and Dilution for Outdoors

A03174

Page 11

CONDENSATE TRAP

Condensate Trap--Upflow Orientation

When the furnace is installed in the upflow position, it is not necessary to relocate the condensate trap or associated tubing. Refer to Fig. 7 for upflow condensate trap information. Refer to Condensate Drain section for information how to install the condensate drain.

Condensate Trap--Downflow Orientation.

When the furnace is installed in the downflow position, the factory--installed trap will be located at the upper left corner of the collector box. When the furnace is installed in the downflow orientation, the factory--installed trap must be relocated for proper condensate drainage.

To Relocate the Condensate Trap:

S Orient the furnace in the downflow position. S Fig. 8 shows the condensate trap and tubing before and after

relocation.

S Refer to the appropriate figure to begin the trap conversion. S Remove the relief tube from the condensate trap. S Remove the screw that secures the condensate trap to the

collector box.

S Remove the trap. S Remove the relief tube from of the port on the collector box. It is

not necessary to remove thehose from the inducer assembly.

S Remove the pressure switch tube from the port on the collector

box.

S Remove the pressure switch tube from the stand--offs on the

inducer assembly

S Loosen the clamp around the inlet of the vent elbow on the

inducer.

S Removethe middle and bottom plugs from the lower right side

of the collector box and set aside. Do Not Discard Plugs.

S Refer to the appropriate figure to begin the trap conversion. S Install the 2 plugs previous removed from the collector box in

the ports where the condensate trap was removed.

S Install the trap over the ports on the lower right side of the

collector box.

S Secure the trap to the collector box with the screw. S Connect the relief tube to the condensate trap to the relief port of

the condensate trap.

S If necessary, slide the relief tube in the inducer stand--offs to

adjust the position of the tube.

S Connect the relief tube to the relief port of the condensate trap. S Route the pressure switch tube to the port on the collector box

next to the condensate trap. Trim off any excesstube to avoid sags or kinks in the tube.

S Rotate the vent elbow to the desired position and tighten the

clamp 15 lb--in.

S Refer to Condensate Drain section for information how to install

the condensate drain.

Condensate Trap--Horizontal Orientation.

When the furnace is installed in the horizontal right position, the factory--installed trap will be located at the bottom left corner of the collector box. When the furnace is installed in the horizontal left position, the factory--installed trap will be located at the top of the collector box. The trap must be repositioned on the collector box for proper condensate drainage.

When the furnace is installed as a direct--vent furnace, a field supplied, accessory Horizontal Installation Kit is required for all horizontal installations. The kit contains a rubber Casing Grommet designed to seal between the furnace casing and the condensate trap.

NOTE: The condensate trap extends below the side of the casing in the horizontal position. A minimum of 2 in. (51 mm) of clearance is required between the casing side and the furnace platform for the trap to extend out of the casing in the horizontal position. In areas where the ambient temperature will fall below 32_ F. ( 0_C), a field--supplied condensate freeze protection kit is required. See Product Data for current kit offering. Follow the instructions included in the kit.

To Relocate the Condensate Trap:

S Remove the knockout in the casing for the Casing Grommet. S Install the grommet in the casing.

NOTE: This grommet is only required for Direct--Vent applications.

S Orient the furnace in the desired position. S Allow for 2 in. (51 mm) of clearance underneath the furnace for

the condensate trap and drain line.

S Fig. 9 shows the condensate trap and tubing before and after

relocation in the horizontal right position.

S Fig. 10 shows the condensate trap and tubing before and after

relocation in the horizontal left position.

S Refer to the appropriate figure to begin the trap conversion. S Remove the relief tube from the condensate trap. S Remove the screw that secures the condensate trap to the

collector box.

S Remove the trap.

Horizontal Left only:

S Remove the relief tube from the port on the collector box. It is

not necessary to remove thetube from the inducer assembly.

S Remove the pressure switch tube from the port on the collector

box.

S Remove the pressure switch tube from the stand--offs on the

inducer assembly.

For Horizontal Right only:

S The pressure switch tube location is not modified. S Loosen the clamp around the inlet of the vent elbow on the

inducer.

S Remove the plugs from the collector box and set aside. Do Not

Discard Plugs.

For Horizontal Left only:

S Removethe middle and right plug from the ports at the bottom

of the collector box.

For Horizontal Right only:

S Remove the plug to the right of the condensate trap. S Refer to the appropriate figure to begin the trap conversion. S Install the plugs previous removed from the collector box in the

ports where the condensatetrap was removed.

S Install the trap over the ports on the lower side of the collector

box.

S Secure the trap to the collector box with the screw. S Connect the relief tube to the condensate trap to the relief port of

the condensate trap.

S If necessary, slide the relief tube in the inducer stand--offs to

adjust the position of the tube.

987MA

Page 12

For Horizontal Left only:

S Connect the relief tube to the relief port of the condensate trap. S Connect the pressure switch tube to the port on the collector box

next to the condensate trap. Trim off any excesstube to avoid sags or kinks in the tube.

S Rotate the vent elbow to the desired position and tighten the

clamp 15 lb--in.

S Refer to Condensate Drain section for information how to install

the condensate drain.

Condensate Drain Protection

Freezing condensate left in condensate trap and drain line may

cause cracks, and possible water damage may occur. Freeze protection of the condensate trap is required when the furnace is installed in the horizontal position and the attic temperature is below 32 deg. F (0 deg. C). If freeze protection for the condensate trap is required, use condensate freeze protection accessory. See Product Data for current kit offering.

The remaining condensate drain line can be protected by using a 3 to 6 watt per ft. (.3M) at 120v and 40_F(4.4_C) self--regulating, shielded, and waterproof heat tape. Wrap field drain pipe with heat tape, approximately 1 wrap per ft. (.3M). Follow manufacturer’s recommendations and installation instructions supplied with heat tape.

987MA

Collector Box

Plugs

Condensate Trap

Relief Port

Fig. 7 -- Upflow Trap Configuration

Vent Pipe Clamp

Pressure Switch

(Appearance May Vary)

Vent Elbow Clamp

Vent Elbow

Collector Box

Plug

Condensate Trap

Relief Port

Condensate Trap

Outlet

Port

A11306

Page 13

Remove relief tube from relief port on condensate trap.

Remove pressure switch tube from pressure switch port.

Remove trap from collector box.

Loosen clamp on inlet to vent elbow.

Install plugs on open ports on collector box.

Connect relief tube to port on collector box.

Route tube through

inducer stand-offs

Remove tube from relief port.

Remove middle and bottom plugs. DO NOT DISCARD.

Trim excess tube.

Connect pressure switch tube to port on collector box.

Attach condensate trap with screw to collector box.

987MA

Rotate elbow to desired position and

tighten clamp to 15 lb.-in.

Slide tube in stand-offs to adjust length.

Connect relief tube to relief port on condensate trap.

Align condensate trap over middle and bottom ports of collector box.

A11277

Fig. 8 -- Downflow Trap Configuration

(Appearance May Vary)

Page 14

Remove plug from collector box. DO NOT DISCARD.

If alternate vent position is required, loosen clamp on inlet of vent elbow.

987MA

Remove trap from collector box.

Unconverted Factory Trap Configuration

As Viewed in the Horizontal Right Orientation

Slide relief tube in stand-offs to adjust length.

Attach condensate trap to collector box with screw.

Install plug in open port on collector box.

Horizontal Right Trap Configuration

Vent elbow shown in alternate orientation. Tighten clamp on inlet to vent elbow 15 lb.-in.

Align trap over middle and right-hand port on collector box.

A11278

Fig. 9 -- Horizontal Right Trap Configuration

(Appearance May Vary)

Page 15

If alternate vent position is required, loosen clamp on vent elbow inlet.

Remove relief tube from port on collector box.

Remove trap from collector box.

Remove relief tube from relief port on condensate trap.

Remove pressure switch tube from port on collector box.

987MA

Remove middle and right plug from collector box.

Unconverted Factory Trap Configuration

As Viewed in the Horizontal Left Orientation

Rotate elbow to desired position and torque clamp on inlet 15 lb.-in.

Slide relief tube in stand-offs to adjust length.

Attach condensate trap to collector box with screw.

Align trap over middle and right-hand port on collector box.

Install plugs in open ports on collector box.

Connect relief tube to port on collector box.

Trim excess tube. Route pressure switch tube underneath relief tube and connect to port on collector box.

Connect relief tube to relief port on condensate trap.

Horizontal Left Trap Configuration

A11279

Fig. 10 -- Horizontal Left Configuration

(Appearance May Vary)

Page 16

CONDENSATE DRAIN CONNECTION

Upflow/Downflow Orientation

In the Upflow or Downflow orientation, the condensate trap is inside the furnace casing. The condensate drain must be routed from the trap through the furnace casing. The condensate drain can be routed through the left or right side of the casing. (The left or right side is as you are viewing the furnace.) The furnace condensate drain can be connected to the Air Conditioning condensate drain as shown in Fig. 12.

NOTE: On narrower casings, it may be easier to remove the condensate trap, connect the drain line components and re-install the condensate trap. Read the steps thoroughly to familiarize yourself with the required steps.

For Right Side Condensate Drain:

1. Remove the 7/8--in. knock--out from the right side of the casing. (See Fig. 11 .)

2. Remove the pre--formed drain tube and two spring clamps from the loose parts bag.

987MA

3. Slide a spring clamp 1 inch (25 mm) down the plain end of the drain tube.

4. From inside the casing, insert the formed grommet end of the tube through the 7/8--in. knockout in the casing.

5. Pull the tube through the casing from the outside until it is seated in the knockout

6. Attach the plain end of the drain tube to the outlet stub on the drain trap. Secure the drain tube to the trap with the spring clamp.

7. Slide a spring clamp over the open end of the drain tube outside the casing.

8. Open the spring clamp and connect a field--supplied 1/2--in. CPVC street elbow to the open end of the drain tube. (See Fig. 13.)

9. Connect additional 1/2--in. CPVC piping to a condensate pump approved for use with acidic furnace condensate or to a code--approved drain.

For Left Side Condensate Drain Connection:

1. For left side condensate drainage, the drain line is routed from the condensate trap, behind the inducer and out through the left side of the casing. A pre-formed “Z” pipe is provided in the loose parts bag shipped with the furnace. The “Z” pipe is long enough to extend out of the casing on the 14 3/16-in. (360 mm) wide furnace. Larger casings will require a field supplied CPVC pipe and to extend the drain line out of the furnace.

2. The “Z” pipe is connected to the condensate trap by modifying the formed rubber drain tube. Connect the drain line as shown below:

3. Remove the knock-out from the left side of the casing. (See Fig. 11.)

4. Install the grommet for the 1/2-in. CPVC drain line in the 7/8-in. knockout in the casing.

5. Remove the pre-formed drain tube, the offset 1/2-in. CPVC pipe and two spring clamps from the loose parts bag.

6. Remove the formed grommet on the tube by cutting the tube along the vertical line located about 1 inch (25 mm) away from the formed grommet.(See Fig. 14.)

7. Slide a spring clamp 1 inch (25 mm) down the plain end of the drain tube.

8. With the bend in the tube oriented horizontally and plain end of the tube pointing away from you, insert the 1/2-in. CPVC pipe into the other end of the drain tube. Rotate the tube so the offset in the tube points away from you. Slide a spring clamp over the open end of the 1/2-in. CPVC tube

and secure the cut end of drain tube to the pipe. (See Fig.

15)

9. Prime the bare end of the pipe with CPVC primer.

10. Route the offset pipe behind the inducer assembly and through the grommet in the casing, if the “Z” pipe is long enough. If the “Z” pipe is not long enough, continue with installation.

11. Attach the plain end of the drain tube to the outlet stub on the drain trap. Secure the drain tube to the trap with the spring clamp.

12. If the “Z” pipe does not extend through the casing, slide a piece of field supplied CPVC through the grommet in the casing, otherwise, go to Step 17.

13. Cement a 1/2-in. CPVC coupling to the end of the CPVC pipe.

14. Apply cement to the end of the “Z” pipe connected to the condensate trap.

15. Connect the field-supplied CPVC pipe to the CPVC pipe connected to the condensate trap.

16. Cut off excess CPVC pipe outside the casing.

17. Connect additional 1/2-in. CPVC piping to a condensate pump approved for use with acidic furnace condensate or to a code-approved drain.

18. When a condensate pump is not used, slope the pipe away from the furnace to allow for proper drainage.

Horizontal Orientation

1. In the Horizontal orientation, a field supplied accessory drain trap grommet is required to seal the gap between the casing and the condensate trap for direct vent applications, only. The condensate trap outlet extends 2 in. (51 mm) below the furnace casing. To allow for servicing the trap, the condensate drain tube in the loose parts bag can be modified to make a coupler to allow for future service of the condensate trap and drain line.

2. Remove the knock-out for the condensate trap in the side of the casing.

3. Install the drain trap grommet in the casing. (For direct vent applications.) If necessary, remove the trap, install the grommet and re-install the trap.

4. Remove the pre-formed drain tube, the offset 1/2-in. CPVC pipe and two spring clamps from the loose parts bag.

5. Remove the formed grommet on the tube to create an elbow or straight connector. (See Fig. 14.)

6. Connect the cut tube to the outlet of the condensate trap with 1 spring clamp.

7. Slide the other spring clamp down the plain end of the drain tube.

8. Connect additional 1/2-in. CPVC piping to the open end of the tube.

9. Slide the spring clamp down over the 1/2-in. CPVC pipe

10. Connect additional 1/2-in. CPVC piping to a condensate pump approved for use with acidic furnace condensate or to a code-approved drain.

11. When a condensate pump is not used, slope the pipe away from the furnace to allow for proper drainage.

Page 17

CAUTION

Cut and remove formed end of drain tube for left side and horizontal drain connection

CUT HAZARD

Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care

and wear appropriate protective clothing, safety glasses and gloves when handling parts, and servicing furnaces.

Fig. 11 -- Knockout Removal

OPEN STAND PIPE FOR A/C OR HUMIDIFIER DRAIN

TEE

TO OPEN DRAIN

Fig. 12 -- Example of Field Drain Attachment

A11305

A11276

RIGHT SIDE DRAIN ELBOW

Fig. 14 -- Modify Drain Tube

Attach tube to condensate trap

Cut formed end o condensate drain tube

Field supplied 1/2” CPVC coupling & drain extension 17 1/2“, 21” and 24 1/2” casing

Field supplied 1/2” CPVC to drain

Casing grommet from loose parts bag

Connect short end of “Z” pipe to modied drain tube

TRAP, DRAIN ELBOW WITH DISCHARGE PIPE

Modied drain tube connect to condensate trap and “Z” pipe

Field-supplied 1/2” CPVC coupling & drain pipe 17 1/2“, 21” and 24 1/2” casings

LEFT SIDE DRAIN ROUTED BEHIND INDUCER

Fig. 15 -- Drain Trap Connection and Routing

(Appearance May Vary)

987MA

A11388

A11344

INSTALL CLAMPS ON DRAIN TUBE ATTACH DRAIN TUBE TO CONDENSATE DRAIN TRAP

PULL DRAIN STUB THROUGH CASING

Fig. 13 -- Formed Tube Grommet

A11342

Remove knockout. Install grommet before relocating condensate trap.

A11348

Fig. 16 -- Horizontal Drain Trap Grommet

Page 18

INSTALLATION

Upflow Installation

NOTE: The furnace must be pitched forward as shown in Fig. 22

for proper condensate drainage.

Supply Air Connections

For a furnace not equipped with a cooling coil, the outlet duct shall be provided with a removable access panel. This opening shall be accessible when the furnace is installed and shall be of such a size that the heat exchanger can be viewed for possible openings using light assistance or a probe can be inserted for sampling the air stream. The cover attachment shall prevent leaks.

Connect supply--air duct to flanges on furnace supply--air outlet. Bend flange upward to 90_ with wide duct pliers. (See Fig. 19.) The supply--air duct must be connected to ONLY the furnace supply--outlet--air duct flanges or air conditioning coil casing (when used). DO NOT cut main furnace casing side to attach supply air duct, humidifier, or other accessories. All accessories MUST be connected to duct external to furnace main casing.

Return Air Connections

987MA

WARNING

FIRE HAZARD

A failure to follow this warning could cause personal injury, death and/or property damage.

Never connect return--air ducts to the back of the furnace. Follow instructions below.

The return--air duct must be connected to bottom, sides (left or right), or a combination of bottom and side(s) of main furnace casing. Bypass humidifier may be attached into unused return air side of the furnace casing. (See Fig. 23, 24, 25.)

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom return--air opening. Remove this panel when bottom return air is used. This panel may be used as the bottom closure of an accessory bottom return air box, or discarded. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove 4 screws holding bottom plate. (See Fig. 21.)

2. Remove bottom plate.

3. Remove bottom closure panel.

4. Reinstall bottom plate and screws.

Side Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom return--air opening. This panel MUST be in place when only side return air is used.

NOTE: Side return--air openings can be used in UPFLOW and some HORIZONTAL configurations. Do not use side return--air openings in DOWNFLOW configuration. (See Fig. 23, 24, 25.)

Leveling Legs (If Desired)

In upflow position with side return inlet(s), leveling legs may be used. (See Fig. 20.) Install field--supplied, 5/16 x 1--1/2 in. (8 x 38 mm) (max) corrosion--resistant machine bolts, washers and nuts.

NOTE: Bottom closure must be used when leveling legs are used. It may be necessary to remove and reinstall bottom closure panel to install leveling legs. To remove bottom closure panel, see Item 1 in Bottom Return Air Inlet section in Step 1 above.

To install leveling legs:

1. Position furnace on its back. Locate and drill a hole in each bottom corner of furnace.

2. For each leg, install nut on bolt and then install bolt with nut in hole. (Install flat washer if desired.)

3. Install another nut on other side of furnace base. (Install flat washer if desired.)

4. Adjust outside nut to provide desired height, and tighten inside nut to secure arrangement.

5. Reinstall bottom closure panel if removed.

Downflow Installation

NOTE: The furnace must be pitched forward as shown in Fig. 22

for proper condensate drainage.

Supply Air Connections

NOTE: For downflow applications, this furnace is approved for

use on combustible flooring when any one of the following 3 accessories are used:

S Special Base, KGASB S Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR S Coil Box Part No. KCAKC

1. Determine application being installed from Table 6.

2. Construct hole in floor per Table 6 and Fig. 18.

3. Construct plenum to dimensions specified in Table 6 and Fig. 18.

4. Install special base coil assembly or coil box as shown in in Fig. 18.

NOTE: It is recommended that the perforated supply--air duct flanges be completely removed from furnace when installing the furnace on a factory--supplied cased coil or coil box. To remove the supply--air duct flange, use wide duct pliers or hand seamers to bend flange back and forth until it breaks off. Be careful of sharp edges. (See Fig. 19.)

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care

and wear appropriate protective clothing, safety glasses and gloves when handling parts, and servicing furnaces.

Connect supply--air duct to supply--air outlet on furnace. Bend flange inward past 90_ with wide duct pliers (See Fig. 19.) The supply--air duct must be connected to ONLY the furnace supply outlet or air conditioning coil casing (when used). When installed on combustible material, supply--air duct must be connected to ONLY the factory--approved accessory subbase, or a factory--approved air conditioning coil casing. DO NOT cut main furnace casing to attach supply side air duct, humidifier, or other accessories. All accessories MUST be connected to duct external to furnace casing.

Return Air Connections

WARNING

FIRE HAZARD

A failure to follow this warning could cause personal injury, death and/or property damage.

Never connect return--air ducts to the back of the furnace. Follow instructions below.

The return--air duct must be connected to return--air opening (bottom inlet). DO NOT cut into casing sides (left or right). Bypass humidifier connections should be made at ductwork or coil casing sides exterior to furnace. (See Fig. 24.)

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom return--air opening. Remove and discard this panel when

Page 19

bottom return air is used in downflow applications. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove 4 screws holding bottom plate. (See Fig. 21.)

2. Remove bottom plate.

3. Remove bottom closure panel.

4. Reinstall bottom plate and screws.

Horizontal Installation

NOTE: The furnace must be pitched forward as shown in Fig. 22

for proper condensate drainage.

WARNING

FIRE, EXPLOSION, AND CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury, death, or property damage.

The furnace can be installed horizontally in an attic or crawlspace on either the left--hand (LH) or right--hand (RH) side. The furnace can be hung from floor joists, rafters or trusses or installed on a non--combustible platform, blocks, bricks or pad.

Platform Furnace Support

Construct working platform at location where all required furnace clearances are met. (See Table 2 and Fig. 26.) For furnaces with 1--in. (25 mm) clearance requirement on side, set furnace on non--combustible blocks, bricks or angle iron. For crawlspace installations, if the furnace is not suspended from the floor joists, the ground underneath furnace must be level and the furnace set on blocks or bricks.

Suspended Furnace Support

The furnace must be supported under the entire length of the furnace with threaded rod and angle iron. (See Fig. 27.) Secure angle iron to bottom of furnace as shown.

Roll--Out Protection

Provide a minimum 12--in. x 22--in. (305 x 559 mm) piece of sheet metal for flame roll--out protection in front of burner area for furnaces closer than 12--in. (305 mm) above the combustible deck or suspended furnaces closer than 12--in. (305 mm) to joists. The sheet metal MUST extend underneath the furnace casing by 1--in. (25 mm) with the door removed.

The bottom closure panel on furnaces of widths 17--1/2--in. (445 mm) and larger may be used for flame roll--out protection when bottom of furnace is used for return air connection. See Fig. 26 for proper orientation of roll--out shield.

Supply Air Connections

Return Air Connections

The return--air duct must be connected to bottom of the furnace. The side of casing that faces downward may also be used for return air connection. A combination of the bottom and downward facing side may also be used. Bypass humidifier may be attached into unused return air side of the furnace casing. (See Fig. 25.)

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom return--air opening. Remove this panel when bottom return air is used. This panel may be used as a roll--out shield or discard. To remove bottom closure panel, perform the following:

1. Tilt or raise furnace and remove 4 screws holding bottom plate. (See Fig. 21.)

2. Remove bottom plate.

3. Remove bottom closure panel.

4. Reinstall bottom plate and screws.

Side Return Air Inlet

These furnaces are shipped with bottom closure panel installed in bottom return--air opening. This panel MUST be in place when side return air inlet(s) are used without a bottom return air inlet.

Not all horizontal furnaces are approved for side return air connections (See Fig. 25.)

Filter Arrangement

WARNING

FIRE, CARBON MONOXIDE AND POISONING HAZARD

Failure to follow this warning could result in fire, personal injury or death.

Never operate a furnace without a filter or filtration device installed. Never operate a furnace with filter or filtration device access doors removed.

There are no provisions for an internal filter rack in these furnaces. An external filter is required.

The furnace is shipped with a factory-supplied Media Filter Cabinet. The Media Filter Cabinet uses either a standard 1-inch (25 mm) filter or 4-inch (102 mm) wide Media Filter which can be purchased separately. A field supplied accessory air cleaner may also be used in place of the media cabinet.

The Media Cabinet is sized for bottom return applications for use in upflow, downflow and horizontal applications. A 16--inch (406 mm) Media Cabinet is shipped with the 14--3/16-in. (360 mm) furnace and includes block-off plates

For upflow side return applications, the Media Cabinet (or field supplied accessory air cleaner) can be installed on the side of the furnace or side and bottom when a bottom plenum is used. (See Fig. 17 and 23.)

For downflow applications, the Media Cabinet (or field supplied accessory air cleaner) must only be connected to the bottom opening on the furnace. See Fig. 17 and 24.

For horizontal applications, the Media Cabinet (or field supplied accessory air cleaner) for all models can be connected to the bottom opening on the furnace. For side return use in the horizontal position, refer to Fig. 25. If both side and bottom openings are used in Fig. 25, each opening used will require a filter.

The media cabinet (or field supplied accessory air cleaner) can also be installed in the common return duct prior to entering the return air opening in any orientation.

Refer to the instructions supplied with Media Cabinet or accessory air filter for assembly and other details. See Table 5 for filter size details.

987MA

Page 20

Table 5 – Filter Size Information -- In. (mm)

FURNACE CASING WIDTH

17 --- 1/2 (445)

21 (533)

24 --- 1/2 (622)

* Recommended to maintain air filter face vel ocity. See Product Data for part number.

SIDE RETURN BOTTOM RETURN

16 x 25 x 3/4

(406 x 635 x 19)

16 x 25 x 3/4

(406 x 635 x 19)

16 x 25 x 3/4

(406 x 635 x 19)

FILTER SIZE

Air Filter Located in Filter Cabinet

FILTER CABINET HEIGHT --- IN (MM) F I L T E R S I Z E --- I N ( M M ) FILTER TYPE

(1) 16 x 25 x 3/4*

16 (406)

987MA

* Filters with a side return ---air may have a different filter size. Measure the filter to obtain the correct size. * Recommended to maintain air filter face vel ocity. See Product Data for part number.

20 (508)

24 (610)

(406 x 635 x 19) or

(1) 16 x 25 x 4---5/16

(406 x 635 x 110)

(1) 20 x 25 x 3/4*

(508 x 635 x 19) or

(1) 20 x 25 x 4---5/16

(508 x 635 x 110)

(1) 24 x 25 x 3/4*or

(610 x 635 x 19) or

(1) 24 x 25 x 4---5/16

(610 x 635 x 110)

16 x 25 x 3/4

(406 x 635 x 19)

20 x 25 x 3/4

(508 x 635 x 19)

24 x 25 x 3/4

(610 x 635 x 19)

FILTER TYPE

Washable*

Washable or Media*

Page 21

14-3/16 and 17-1/2-in.

Furnace

21-in. Furnace

4-Ton or less, AC

capacity airflow

4-in. Block Off Plate

Screws

1/2-in.

16-in. Media Cabinet

Media Cabinet Installation

Side Return

21- or 24-1/2-in.

Furnace

Up to 5-Ton AC

capacity airflow

20- or 24-in. Media

Cabinet

Bottom Return Plenum

20- or -24-in. Media Cabinet Installation

for Combination Side and Bottom Return

20-in. Media Cabinet

Media Cabinet Installation Option for

4-Ton or Less A/C Capacity

21-in. Furnace up to 5-Ton AC Capacity

24-1/2-in. Furnace up to 4-Ton AC Capacity

45°

Transition

20- or 24-in. Media Cabinet

20- or -24-in. Media Cabinet Installation

with Angled Transition

987MA

14-3/16-in. Furnace

Screw

Filler plates

14--3/16-in. Furnace with Filler Plates, Centered

14-3/16-in. Furnace

Screws

Screw

Filler plate

14--3/16-in. Furnace with Filler Plates, Off--Set to Right

A11437

Fig. 17 -- Media Filter

Page 22

FURNACE

(OR COIL CASING

WHEN USED)

FURNACE

APPROVED

COIL ASSEMBLY

COIL BOX

987MA

FURNACE

CASING

WIDTH

IN. (mm)

17–1/2

(445)

(533)

24 --- 1/2

(622)

PLENUM

OPENING

FLOOR

OPENING

COMBUSTIBLE

FLOORING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

FLOOR

OPENING

Fig. 18 -- Installation on Combustible Flooring

Table 6 – Opening Dimensions -- In. (mm)

APPLICATION

Upflow Applications on Combustible or Noncombustible Floor-

Downflow Applications on Noncombustible Flooring (KGASB

Downflow applications on combustible flooring (KGASB sub-

Downflow Applications on Combustible Flooring with CNPV,

CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB

Upflow Applications on Combustible or Noncombustible Floor-

Downflow Applications on Noncombustible Flooring (KGASB

Downflow applications on combustible flooring (KGASB sub-

Downflow Applications on Combustible Flooring with CNPV,

CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB

Upflow Applications on Combustible or Noncombustible Floor-

Downflow Applications on Noncombustible Flooring (KGASB

Downflow applications on Combustible flooring (KGASB sub-

Downflow Applications on Combustible Flooring with CNPV,

CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB

ing (KGASB subbase not required)

subbase not required)

base required)

subbase not required)

ing (KGASB subbase not required)

subbase not required)

base required)

subbase not required)

ing (KGASB subbase not required)

subbase not required)

base required)

subbase not required)

COMBUSTIBLE

FLOORING

SHEET METAL

PLENUM

FLOOR

OPENING

PLENUM OPENING FLOOR OPENING

A B C D

(406)

15--- 7/8

(403)

15--- 1/8

(384)

15--- 1/2

(394)

19--- 1/2

(495)

19--- 3/8

(492)

18--- 5/8

(473)

(483)

(584)

22--- 7/8

(581)

22--- 1/8

(562)

22--- 1/2

(572)

21--- 5/8

(549)

(483)

21--- 5/8

(549)

(483)

21--- 1/8

(537)

(483)

16--- 5/8

(422)

16--- 1/2

(419)

16--- 3/4

(425)

16--- 1/2

(419)

20--- 1/8

(511)

(508)

20--- 1/4

(514)

(508)

23--- 5/8

(600)

23--- 1/2

(597)

23--- 3/4

(603)

23--- 1/2

(597)

22--- 1/4

(565)

19--- 5/8

(498)

20--- 5/8

(600)

(508)

22--- 1/4

(565)

19--- 5/8

(498)

20--- 5/8

(600)

(508)

22--- 1/4

(565)

19--- 5/8

(498)

20--- 5/8

(600)

(508)

A10491

Page 23

PERFORATED DISCHARGE DUCT FLANGE

UPFLOW DOWNFLOW HORIZONTAL

90°

(8mm)

(44mm)

1 3 / 4 ″

120°

MIN

YES

120°

MIN

YES

120° MIN

YES

987MA

A10493

Fig. 19 -- Duct Flanges

″

(8mm)

″

/ 4 ″

1 (44mm)

(8mm)

″

(44mm)

4 ″

(44mm)

Fig. 20 -- Leveling Legs

LEVEL 0-IN. (0 MM) TO 1/2-IN. (13 MM) MAX

(8mm)

″

UPFLOW OR DOWNFLOW

A89014

Fig. 21 -- Removing Bottom Closure Panel

MIN 1/4-IN. (6 MM) TO 1/2-IN. (13 MM) MAX

HORIZONTAL

Fig. 22 -- Furnace Pitch Requirements

BOTTOM CLOSURE PAN EL

BOTTOM PLA TE

A11092

A11237

Page 24

ANY COMBINATION OF 1, 2, OR 3 PERMITTED.

987MA

Fig. 23 -- Upflow Return Air Configurations and Restrictions

Fig. 25 -- Horizontal Return Air Configurations

A11036

HORIZONTAL TOP RETURN NOT PERMITTED FOR ANY MODEL

and Restrictions

A11037

Fig. 24 -- Downflow Return Air Configurations

and Restrictions

A11038

Page 25

COMBUSTION - AIR PIPE (SEE VENTING SECTION)

2-IN.

(51 mm)

30 IN. (762 mm)

MIN. WORK AREA

987MA

ROLLOUT PROTECTION REQUIRED

Install 12” x 22” (305 x 559 mm) sheet metal in front of burner compartment area.

Fig. 26 -- Working Platform for Attic Installation

COMBUSTION-AIR PIPE (SEE VENTING SECTION)

2-IN.

(51 mm)

A11154

A11155

Fig. 27 -- Suspended Furnace Installation

Page 26

AIR DUCTS

General Requirements

The duct system should be designed and sized according to accepted national standards such as those published by: Air Conditioning Contractors Association (ACCA), Sheet Metal and Air Conditioning Contractors National Association (SMACNA) or American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) or consult The Air Systems Design Guidelines reference tables available from your local distributor. The duct system should be sized to handle the required system design CFM at the design external static pressure. The furnace airflow rates are provided in Table 7--Air Delivery--CFM (With Filter). When a furnace is installed so that the supply ducts carry air circulated by the furnace to areas outside the space containing the furnace, the return air shall also be handled by duct(s) sealed to the furnace casing and terminating outside the space containing the furnace.

Secure ductwork with proper fasteners for type of ductwork used. Seal supply-- and return--duct connections to furnace with code approved tape or duct sealer.

987MA

NOTE: Flexible connections should be used between ductwork and furnace to prevent transmission of vibration.

Ductwork passing through unconditioned space should be insulated to enhance system performance. When air conditioning is used, a vapor barrier is recommended.

Maintain a 1--in. (25 mm) clearance from combustible materials to supply air ductwork for a distance of 36--in. (914 mm) horizontally from the furnace. See NFPA 90B or local code for further requirements.

Ductwork Acoustical Treatment

NOTE: Metal duct systems that do not have a 90 degree elbow

and 10 ft. (3 M) of main duct to the first branch take--off may require internal acoustical lining. As an alternative, fibrous ductwork may be used if constructed and installed in accordance with the latest edition of SMACNA construction standard on fibrous glass ducts. Both acoustical lining and fibrous ductwork shall comply with NFPA 90B as tested by UL Standard 181 for Class 1 Rigid air ducts.

NOTE: For horizontal applications, the top most flange may be bent past 90_ to allow the evaporator coil to hang on the flange temporarily while the remaining attachment and sealing of the coil are performed.

Page 27

INPUT

BTUH

Table 7 – Air Delivery -- CFM (With Filter)

(SW1-5 and SW4-3 set to OFF, except as indicated. See Notes 1 and 2.)

Cooling Switch Settings External Static Pressure (E.S.P.)

SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

OFF OFF OFF 1060 1070 1080 1080 1075 1065 1050 1035 1025 1010

OFF OFF ON 545 530 520 525 510

OFF ON OFF 710 710 710 695 690

OFF ON ON 875 880 890 895 895 890 885 880 870 855

ON OFF OFF 1060 1070 1080 1080 1075 1065 1050 1035 1025 1010

60000

INPUT

BTUH

80000

ON OFF ON 1235 1240 1250 1255 1255 1250 1230 1190 1155 1115

ON ON OFF 1235 1240 1250 1255 1255 1250 1230 1190 1155 1115

ON ON ON 1235 1240 1250 1255 1255 1250 1230 1190 1155 1115

Maximum Cooling Airflow

Maximum Heat Airflow

Intermediate Heat Airflow

Minimum Heat Airflow

1425 1425 1405 1370 1335 1300 1260 1225 1190 1155

1075 1085 1095 1095 1090 1080 1065 1050 1035 1020

535 515 505 515 495

420 410 415 400 380

Cooling Switch Settings External Static Pressure (E.S.P.)

SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

OFF OFF OFF 1055 1065 1080 1075 1065 1050 1045 1035 1025 1005

OFF OFF ON 520 505 505 495 490

OFF ON OFF 665 685 680 660 665

OFF ON ON 885 895 905 900 900 895 885 875 860 845

ON OFF OFF 1055 1065 1080 1075 1065 1050 1045 1035 1025 1005

ON OFF ON 1245 1245 1255 1255 1260 1255 1250 1235 1220 1185

ON ON OFF 1245 1245 1255 1255 1260 1255 1250 1235 1220 1185

ON ON ON 1245 1245 1255 1255 1260 1255 1250 1235 1220 1185

Maximum Cooling Airflow

Maximum Heat Airflow

Intermediate Heat Airflow

Minimum Heat Airflow

1520 1485 1450 1415 1375 1335 1300 1265 1225 1190

755 745 755 755 765

620 625 630 620 610

987MA

Page 28

INPUT

BTUH

Table 7 -- Air Delivery -- CFM (With Filter) (Continued)

(SW1-5 and SW4-3 set to OFF, except as indicated. See Notes 1 and 2.)

Cooling Switch Settings External Static Pressure (E.S.P.)

SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

OFF OFF OFF 1815 1810 1805 1800 1785 1765 1745 1720 1710 1685

OFF OFF ON 765 775 755 730 710

OFF ON OFF 930 940 935 930 935

OFF ON ON 1095 1120 1120 1105 1095 1100 1085 1075 1055 1050

ON OFF OFF 1245 1270 1275 1280 1290 1280 1285 1270 1260 1245

100000

ON OFF ON 1440 1445 1455 1445 1450 1440 1440 1425 1415 1405

ON ON OFF 1815 1810 1805 1800 1785 1765 1745 1720 1710 1685

ON ON ON 1815 1810 1805 1800 1785 1765 1745 1720 1710 1685

2055 2055 2050 2045 2030 2015 1995 1940 1870 1805

1495 1515 1515 1520 1525 1520 1515 1505 1490 1480

900 905 900 900 890

725 725 720 690 670

987MA

INPUT

BTUH

Maximum Cooling Airflow

Maximum Heat Airflow

Intermediate Heat Airflow

Minimum Heat Airflow

Cooling Switch Settings External Static Pressure (E.S.P.)

SW2-3 SW2-2 SW2-1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

OFF OFF OFF 1850 1855 1860 1855 1850 1830 1805 1775 1750 1730

OFF OFF ON 765 745 740 705 680

OFF ON OFF 930 925 915 900 885

OFF ON ON 1095 1100 1110 1105 1085

ON OFF OFF 1265 1255 1265 1280 1275 1285 1270 1260 1250 1230

120000

ON OFF ON 1465 1455 1470 1465 1465 1470 1455 1450 1435 1415

ON ON OFF 1850 1855 1860 1855 1850 1830 1805 1775 1750 1730

ON ON ON 2200 2200 2200 2190 2185 2170 2145 2085 1990 1890

Maximum Cooling Airflow

Maximum Heat Airflow

Intermediate Heat Airflow

Minimum Heat Airflow

2200 2200 2200 2190 2185 2170 2145 2085 1990 1890

1815 1820 1825 1820 1815 1795 1775 1745 1720 1700

1095 1100 1110 1105 1085

905 900 890 875 855

1. Nominal 350 CFM/ton cooling airflow is delivered with SW1-5 and SW4-2 set to OFF.

Set SW1-5 to ON for nominal 400 CFM/ton (+15% airflow). Set SW4-3 to ON for nominal 325 CFM/ton (-7% airflow). Set both SW1-5 and SW4-3 to ON for nominal 370 CFM/ton (+7% airflow).

2. Maximum cooling airflow is achieved when switches SW3-1, SW3-2, SW3-3 and SW1-5 are set to ON, and SW4-3 is set to OFF.

3. All heating CFM's are when minimum/intermediate heat rise adjustment switch (SW1-3) and comfort/efficiency adjustment switch (SW1-4) are both set to OFF.

4. Ductwork must be sized for maximum-heating CFM within the operational range of E.S.P. Operation within the blank areas of the chart is not recommended

because maximum-heat operation will be above 1.0 E.S.P.

5. All airflows on 21" (533 mm) casing size furnaces are 5% less on side return only installations.

6. Side returns for 24.5" (622 mm) casing sizes require two sides, or side and bottom, to allow sufficient airflow at the return of the furnace.

Page 29

GAS PIPING

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Never purge a gas line into a combustion chamber. Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically for the detection of leaks to check all connections. A fire or explosion may result causing property damage, personal injury or loss of life.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Use proper length of pipe to avoid stress on gas control manifold and gas valve.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Gas valve inlet and/or inlet pipe must remain capped until gas supply line is permanently installed to protect the valve from moisture and debris. Also, install a sediment trap in the gas supply piping at the inlet to the gas valve.

Gas piping must be installed in accordance with national and local codes. Refer to current edition of NFGC in the U.S.A. Refer to current edition of CAN/CSA B149.1 in Canada.

Installations must be made in accordance with all authorities having jurisdiction. If possible, the gas supply line should be a separate line running directly from meter to furnace.

NOTE: Use a back--up wrench on the inlet of the gas valve when connecting the gas line to the gas valve.

NOTE: In the state of Massachusetts:

1. Gas supply connections MUST be performed by a licensed plumber or gas fitter.

2. When flexible connectors are used, the maximum length shall not exceed 36 in. (915 mm).

3. When lever handle type manual equipment shutoff valves are used, they shall be T--handle valves.

4. The use of copper tubing for gas piping is NOT approved by the state of Massachusetts.

Refer to Table 8 for recommended gas pipe sizing. Risers must be used to connect to furnace and to meter. Support all gas piping with appropriate straps, hangers, etc. Use a minimum of 1 hanger every 6 ft. (1.8 M). Joint compound (pipe dope) should be applied sparingly and only to male threads of joints. Pipe dope must be resistant to the action of propane gas.

WARNING

FIRE OR EXPLOSION HAZARD

A failure to follow this warning could result in personal injury, death, and/or property damage.

If local codes allow the use of a flexible gas appliance connector, always use a new listed connector. Do not use a connector which has previously served another gas appliance. Black iron pipe shall be installed at the furnace gas control valve and extend a minimum of 2--in. (51 mm) outside the furnace.

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in furnace damage. Connect gas pipe to furnace using a backup wrench to

avoid damaging gas controls and burner misalignment.

An accessible manual equipment shutoff valve MUST be installed external to furnace casing and within 6 ft. (1.8 M) of furnace.

Install a sediment trap in riser leading to furnace as shown in Fig.

29. Connect a capped nipple into lower end of tee. Capped nipple should extend below level of furnace gas controls. Place a ground joint union between furnace gas control valve and exterior manual equipment gas shutoff valve.

A 1/8--in. (3 mm) NPT plugged tapping, accessible for test gauge connection, MUST be installed immediately upstream of gas supply connection to furnace and downstream of manual equipment shutoff valve.

Piping should be pressure and leak tested in accordance with the current addition of the NFGC in the United States, local, and national plumbing and gas codes before the furnace has been connected. Refer to current edition of NSCNGPIC in Canada. After all connections have been made, purge lines and check for leakage at furnace prior to operating furnace.

NOTE: The furnace gas control valve inlet pressure tap connection is suitable to use as test gauge connection providing test pressure DOES NOT exceed maximum 0.5 psig (14--In. W.C.) stated on gas control valve. (See Fig. 50.)

If pressure exceeds 0.5 psig (14--In. W.C.), gas supply pipe must be disconnected from furnace and capped before and during supply pipe pressure test. If test pressure is equal to or less than 0.5 psig (14--In. W.C.), turn off electric shutoff switch located on furnace gas control valve and accessible manual equipment shutoff valve before and during supply pipe pressure test. After all connections have been made, purge lines and check for leakage at furnace prior to operating furnace.

The gas supply pressure shall be within the maximum and minimum inlet supply pressures marked on the rating plate with the furnace burners ON and OFF.

Some installations require gas entry on right side of furnace (as viewed in upflow). (See Fig. 28.)

Gas Pipe Grommet

For direct vent (2-pipe) applications, the knockout for the gas pipe must be sealed to prevent air leakage. Remove the knockout, install the grommet in the knockout, then insert the gas pipe. The grommet is included in the loose parts bag. See Fig. 28.

987MA

Page 30

Table 8 – Maximum Capacity of Pipe

NOMINAL

IRON PIPE

SIZE

IN. (MM)

1/2 (13) 175 120 97 82 73 3/4 (19) 360 250 200 170 151

1 ( 25) 680 465 375 320 285 1-1/4 (32) 1400 950 770 660 580 1-1/2 (39) 2100 1460 1180 990 900

* Cubic ft of gas per hr for gas pressures o f 0.5 psig (14---In. W.C.) or less and a pressure drop of 0.5 --- In. W.C. (based on a 0.60 specific gravit y gas). Ref: Table 8 above and 6.2 of NFPA54/ANSI Z223.1--- 2009.

Left Side Gas Entry. Gas Pipe Grommet Required For Direct Vent Applications.

(3.0)20(6.0)30(9.1)40(12.1)50(15.2)

LENGTH OF PIPE --- FT (M)

Gas Pipe Grommet Required For Direct Vent Applications

987MA

Fig. 28 -- Gas Entry

GAS

SUPPLY

FRONT

MANUAL SHUT OFF VALV E (REQUIRED)

SEDIMENT TRAP

UNION

Fig. 29 -- Typical Gas Pipe Arrangement

NOTE: Union may be inside the vestibule where permitted by local codes.

ELECTRICAL CONNECTIONS

A11338

A11035

Field--supplied wiring shall conform with the limitations of 63_F (33_C) rise.

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, or property damage.

The cabinet MUST have an uninterrupted or unbroken ground according to NEC ANSI/NFPA 70--2011 or local codes to minimize personal injury if an electrical fault should occur. In Canada, refer to Canadian Electrical Code CSA C22.1. This may consist of electrical wire, conduit approved for electrical ground or a listed, grounded power cord (where permitted by local code) when installed in accordance with existing electrical codes. Refer to the power cord manufacturer’s ratings for proper wire gauge. Do not use gas piping as an electrical ground.

CAUTION

FURNACE MAY NOT OPERATE HAZARD

Failure to follow this caution may result in intermittent furnace operation.

Furnace control must be grounded for proper operation or else control will lock out. Control must remain grounded through green/yellow wire routed to gasvalve and manifold bracket screw.

115-- V Wiring

Furnace must have a 115-v power supply properly connected and grounded.

NOTE: Proper polarity must be maintained for 115-v wiring. If polarity is incorrect, control LED status indicator light will flash rapidly and furnace will NOT operate.

Verify that the voltage, frequency, and phase correspond to that specified on unit rating plate. Also, check to be sure that service provided by utility is sufficient to handle load imposed by this equipment. Refer to rating plate or Table 9 for equipment electrical specifications.

U.S.A. Installations: Make all electrical connections in accordance with the current edition of the National Electrical Code (NEC) ANSI/NFPA 70 and any local codes or ordinances that might apply.

Canada Installations: Make all electrical connections in accordance with the current edition of the Canadian Electrical Code CSA C22.1 and any local codes or ordinances that might apply.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal

injury or death.

Blower door switch opens 115--v power to control. No

component operation can occur. Do not bypass or close

switch with blower door removed.

See Fig. 33 for field wiring diagram showing typical field 115--v wiring. Check all factory and field electrical connections for tightness.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death, or property damage.

Do not connect aluminum wire between disconnect switch and furnace. Use only copper wire. See Fig. 31.

Use a separate, fused branch electrical circuit with a properly sized fuse or circuit breaker for this furnace. See Table 9 for wire size and fuse specifications. A readily accessible means of electrical disconnect must be located within sight of the furnace.

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J--Box Installation

WARNING

FIRE OR ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal

injury, death, or property damage.

If field--supplied manual disconnect switch is to be mounted

on furnace casing side, select a location where a drill or

fastener cannot damage electrical or gas components.

The J-Box is used when field line voltage electrical connections are made to the furnace wiring harness inside the furnace casing. The J-Box is not required if a field-supplied electrical box is attached to the outside of the furnace casing and the box is grounded to the green ground wire of the main wiring harness and the earth ground of the field electrical supply.

The J--Box cover, mounting bracket and screws are shipped in the loose parts bag included with the furnace. The J--Box can be mounted on the left or right side of the casing, as viewed from the upflow position.

Remove the J--Box cover and mounting bracket from the loose parts bag. Select a 7/8--in. (22 mm) knock-out on the desired side of the casing. Remove the knock-out from the casing. Drill two (2) 1/8--in. (3 mm) pilot holes in the casing dimples by the desired 7/8--in. (22 mm) knock-out.

Align the J--box mounting bracket against the inside of the casing and secure the mounting bracket with the screws. (See Fig. 30.)

Electrical Box on Furnace Casing Side

NOTE: Check that duct on side of furnace will not interfere with

installed electrical box.

1. Fasten a field-supplied external electrical box to the outside of the casing by driving two field-supplied screws from inside electrical box into casing. (See Fig. 31.)

2. Route field power wiring into external electrical box.

3. Pull furnace power wires through 1/2-in. (12 mm) diameter hole in J-Box. If necessary, loosen power wires from strain-relief wire-tie on furnace wiring harness.

4. Connect any code required external disconnect(s) to field power wiring.

5. Route external field power wires through holes in electrical box and casing.

6. Connect field ground wire and factory ground wire to green ground screw on J--Box mounting bracket as shown in Fig.

30.

7. Connect field power and neutral leads to furnace power leads as shown in Fig. 33.

8. Attach furnace J-Box cover to mounting bracket with screws supplied in loose parts bag. Do not pinch wires between cover and bracket.

9. Complete external disconnect wiring and installation. Connect line voltage leads as shown in Fig. 31. Use best practices (NEC in U.S.A. for wire bushings, strain relief, etc., CANADA: Canadian Electrical Code CSA C22.1)

Power Cord Installation in Furnace J--Box

NOTE: Power cords must be able to handle the electrical

requirements listed in Table 9. Refer to power cord manufacturer’s listings.

1. Install J--Box mounting bracket to inside of furnace casing. (See Fig. 30.)

2. Route listed power cord through 7/8--in. (22 mm) diameter hole in casing and J--Box bracket.

3. Secure power cord to J--Box bracket with a strain relief bushing or a connector approved for the type of cord used.

4. Pull furnace power wires through 1/2--in. (12 mm) diameter hole in J--Box. If necessary, loosen power wires from strain—relief wire--tie on furnace wiring harness.

5. Connect field ground wire and factory ground wire to green ground screw on J--Box mounting bracket as shown in Fig.

30.

6. Connect power cord power and neutral leads to furnace power leads as shown in Fig. 33.

7. Attach furnace J--Box cover to mounting bracket with screws supplied in loose parts bag. Do not pinch wires between cover and bracket. (See Fig. 30).

BX Cable Installation in Furnace J--Box

1. Install J--Box mounting bracket to inside of furnace casing. See Fig. 30.

2. Route BX connector through 7/8--in. (22 mm) diameter hole in casing and J--Box bracket.

3. Secure BX cable to J--Box bracket with connectors approved for the type of cable used.

4. Connect field ground wire and factory ground wire to green ground screw on J--Box mounting bracket as shown in Fig.

30.

5. Connect field power and neutral leads to furnace power leads. as shown in Fig. 33.

6. Attach furnace J--Box cover to mounting bracket with screws supplied in loose parts bag. Do not pinch wires between cover and bracket.

24--V Wiring

Make field 24--v connections at the 24--v terminal strip. (See Fig.

34.) Connect terminal Y/Y2 as shown in Fig. 33 for proper cooling operation. Use only AWG No. 18, color--coded, copper thermostat wire.

NOTE: Use AWG No. 18 color-coded copper thermostat wire for lengths up to 100 ft. (30.5 M). For wire lengths over 100 ft., use AWG No. 16 wire.

The 24--v circuit contains an automotive--type, 3--amp. fuse located on the control. Any direct shorts during installation, service, or maintenance could cause this fuse to blow. If fuse replacement is required, use ONLY a 3--amp. fuse of identical size. See Fig. 34.

Thermostats

For best results, use a communicating wall control to control this modulating furnace. A single stage or two--stage heating and cooling thermostat can be used with the furnace. The furnace control board CPU will control the furnace and outdoor unit staging. A two stage heating and cooling thermostat can also be used to control the staging. However, full modulating capability will not be available when the furnace staging is controlled by the thermostat. Furnace staging will be limited to Minimum and Maximum inputs or Intermediate and Maximum inputs depending on the configuration of set-up switches SW1-2 and SW4-2. For two stage thermostat control of a 2-stage outdoor unit, remove the ACRDJ jumper from the furnace control board. Refer to typical thermostat wiring diagrams and the Sequence of Operation section for additional details. Consult the thermostat installation instructions for specific information about configuring the thermostat. See Fig. 34 and 35.

Accessories (See Fig. 32 and 34.)

1. Electronic Air Cleaner (EAC) Connect an accessory Electronic Air Cleaner (if used) using 1/4--in. female quick connect terminals to the two male 1/4--in. quick--connect terminals on the control board marked EAC--1 and EAC--2. The terminals are rated for 115VAC, 1.0 amps maximum and are energized during blower motor operation.

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Page 32

2. Humidifier (HUM)

The HUM terminal is a 24 VAC output, energized when the blower is operating during a call for heat.

Connect an accessory 24 VAC, 0.5 amp. maximum humidifier (if used) to the ¼--in. male quick--connect HUM terminal and COM--24V screw terminal on the control board thermostat strip.

NOTE: If the humidifier has its own 24 VAC power supply, an isolation relay may be required. Connect the 24 VAC coil of the isolation relay to the HUM and COM/24V screw terminal on the control board thermostat strip. (See Fig. 32.)

3. Communication Connector (ABCD connection) This connection is used when the furnace is controlled by

Alternate Power Supplies

This furnace is designed to operate on utility generated power which has a smooth sinusoidal waveform. If the furnace is to be operated on a generator or other alternate power supply, the alternate power supply must produce a smooth sinusoidal waveform for compatibility with the furnace electronics. The alternate power supply must generate the same voltage, phase, and frequency (Hz) as shown in Table 9 or the furnace rating plate.

Power from an alternate power supply that is non-sinusoidal may damage the furnace electronics or cause erratic operation.

Contact the alternate power supply manufacturer for specifications and details.

an optional communicating User Interface instead of a standard thermostat. The ABCD plug is supplied with the User Interface. Refer to the instructions supplied with the User Interface for complete details. See Fig. 34.

4. Outside Air Thermistor (OAT) The OAT connection is used in conjunction with communicating User Interface. It is not required when the furnace

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is controlled by a standard type thermostat. Refer to the instructions supplied with the User Interface for complete details.

Table 9 – Electrical Data

MODULATING

UNIT SIZE V O LT S ---

60,000 1 1 5 --- 6 0 --- 1 127 104 9.7 12.7 14 29 (8.8) 15

80,000 1 1 5 --- 6 0 --- 1 127 104 9.7 12.7 14 29 (8.8) 15 100,000 1 1 5 --- 6 0 --- 1 127 104 14.8 19.1 12 30 (9.1) 20 120,000 1 1 5 --- 6 0 --- 1 127 104 14.8 19.1 12 30 (9.1) 20

* Permissible limits of the voltage range at which th e unit operates satisfactorily. # Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier,

etc.) full load amps.

{Time---delay type is recommended. }Length shown is as measured one way along wire path between furnace and service panel for maximum 2 percent voltage drop.

H E R T Z ---

PHASE

OPERATING VOLTAGE

RANGE*

Maximum* Minimum*

MAXIMUM

UNIT

AMPS

UNIT

AMPACITY#

MINIMUM

WIRE

SIZE AWG

MAXIMUM

WIRE

LENGTH

FT (M)}

FUSE OR CKT

MAXIMUM

BKR

AMPS{

Page 33

J BOX LOCATIONS

J−BO X MOUNTING SCREWS

J−BO X MOUNTING BRACKET

GROUND SCREW

J−BOX COVER

NEUTRAL

LINE VOLTAGE

DISCONNECT

GROUND

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ELECTRIC

SWITCH

COPPER

WIRE ONLY

Fig. 30 -- Installing J--Box (When Used)

(Appearance May Vary)

A11156

ALUMINUM

WIRE

A11146

Fig. 31 -- Field--Supplied Electrical Box on Furnace Casing

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To Humidifier Leads

To HUM Terminal On

Furnace Control Board

24 V

Coil

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To Humidifier Leads

BLOWER

DOOR

SWITCH

BLK

WHT

GND

115-VOLT FIELD-

SUPPLIED

FUSED

DISCONNECT

To Com/24V Screw Terminal

on Thermostat Strip

Fig. 32 -- Field--supplied Isolation Relay for Humidifiers with Internal Power Supply

FIELD 24-VOLT WIRING FIELD 115-, 208/230-, 460-VOLT WIRING FACTORY 24-VOLT WIRING FACTORY 115-VOLT WIRING

BLK

WHT

JUNCTION BOX

FIVE

WIRE

THREE-WIRE

HEATING-

ONLY

FURNACE

COM

O N

W/W1

Y/Y2

R O

24-VOLT

TERMINAL

BLOCK

NOTE 2

WCY RG

NOTE 1

NOTES: 1.

Connect Y/Y2-terminal as shown for proper operation. Some thermostats require a "C" terminal connection as shown.

2. If any of the original wire, as supplied, must be replaced, use

3. same type or equivalent wire.

1-STAGE THERMOSTAT TERMINALS

CONDENSING

UNIT

FIELD-SUPPLIED

FUSED DISCONNECT

GND

A11157

208/230- OR 460-VOLT THREE PHASE

208/230VOLT SINGLE PHASE

A11401

Fig. 33 -- Typical Two--Stage Field Wiring Diagram

Page 35

24-V THERMOSTAT

TERMINALS

PL2 – HOT SURFACE

IGNITER & INDUCER

MOTOR CONNECTOR

115-VAC (L2) NEUTRAL

CONNECTIONS

115-VAC (L1) LINE

VOLTAGE CONNECTIONS

EAC-1 TERMINAL

(115-VAC 1.0 AMP MAX.)

PL1 – LOW VOLTAGE MAIN

HARNESS CONNECTOR

PL3 – ECM BLOWER

HARNESS

CONNECTOR

TRANSFORMER 24-VAC

CONNECTIONS

3-AMP FUSE

STATUS AND COMM

LED LIGHTS

SW1 SETUP

SWITCHES AND

BLOWER OFF-

DELAY

MODEL PLUG CONNECTOR

AIR CONDITIONING

(A/C) AIRFLOW

SETUP SWITCHES

COMMUNICATION

CONNECTOR

CONTINUOUS FAN

(CF) AIRFLOW

SETUP SWITCHES

OUTDOOR

AIR TEMP

CONNECTOR

HUMIDIFIER

TERMINAL (24-VAC

0.5 AMP MAX.

ACRDJ – AIR

CONDITIONING

RELAY DISABLE

JUMPER

FLASH

UPGRADE

CONNECTOR

(FACTORY

ONLY)

SW4 SETUP

SWITCHES

SOFTWARE

VERSION

PART NUMBER AND

DATE CODE WWYY

PL8 - MODULATING

GAS VALVE

CONNECTOR

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A11425

Fig. 34 -- Modulating Furnace Control

Page 36

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THERMOSTAT

11, and 16

Modulating and 2-Stage Furnace with Single-Speed Air Conditioner

THERMOSTAT

15, and 16

Modulating and 2-Stage Furnace with Single-Speed Heat Pump

THERMOSTAT

Modulating and 2-Stage Furnace with Two-Speed Air Conditioner

12 and 16

Modulating and 2-Stage Furnace with Two-Speed Heat Pump

Fig. 35 -- Thermostat Wiring Diagrams

15, and 16

A11274

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NOTES FOR THERMOSTAT WIRING DIAGRAMS

1. Heat pump MUST have a high pressure switch for dual fuel applications.

2. Refer to outdoor equipment Installation Instructions for additional information and setup procedure.

3. If the heat pump date code is 1501E or earlier, select the “ZONE” position on the two speed heat pump control. Heat pumps with date code 1601E and later do not have or require a “ZONE” selection.

4. Outdoor Air Temperature - sensor must be attached in all dual fuel applications.

5. Configure the thermostat for air conditioner installations. Refer to thermostat instructions.

6. Configure thermostat for heat pump installations. Refer to thermostat instructions.

7. Configure thermostat for single-stage compressor operation. Refer to thermostat instructions.

8. Configure thermostat for two-stage compressor operation. Refer to thermostat instructions.

9. Configure thermostat for Dual Fuel Operation. Refer to thermostat instructions.

10. NO connection should be made to the furnace HUM terminal when using a thermostat with a 24 volt humidifier output.

11. Optional connection - If wire is connected to W2 on furnace control board, either dip switch SW1-2 or SW4-2 on furnace control should be set in ON position to allow thermostat to control furnace at 2 stages Min/Max or Intermediate/Max.

12. Optional connection - If wire is connected, ACRDJ jumper on furnace control should be removed to allow thermostat to control outdoor unit staging.

13. Furnace must control its own staging operation via furnace control algorithm. This is factory default.

14. The RVS Sensing terminal “L” should not be connected. This is internally used to sense defrost operation.

15. If thermostat has internal control of heat pump balance point, DO NOT SELECT the “FURNACE INTERFACE” or “BALANCE POINT” option on the two-speed heat pump control board. Refer to thermostat instructions

16. Configure Dehumidify function to remove 24 VAC from Dehum terminal on a demand to dehumidify.

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Page 38

VENTING

Furnace is set in place in the required orientation.

Special Venting Requirements for Installations in Canada

Installation in Canada must conform to the requirements of CAN/CSA B149 code. Vent systems must be composed of pipe, fittings, cements, and primers listed to ULC S636. The special vent fittings and accessory concentric vent termination kits and accessory external drain trap have been certified to ULC S636 for use with those Royal Pipe and IPEX PVC vent components which have been certified to this standard. In Canada, the primer and cement must be of the same manufacturer as the vent system – GVS-65 Primer (Purple) for Royal Pipe or IPEX System 636, PVC/CPVC Primer, Purple Violet for Flue Gas Venting and GVS-65 PVC Solvent Cement for Royal Pipe or IPEX System

t, PVC Cement for Flue Gas Venting, rated Class IIA, 65 deg

636

(1)

C. must be used with this venting system - do not mix primers and cements from one manufacturer with a vent system from a different manufacturer. Follow the manufacturer’s instructions in the use of primer and cement and never use primer or cement beyond its

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expiration date. The safe operation, as defined by ULC S636, of the vent system is

based on following these installation instructions, the vent system manufacturer’s installation instructions, and proper use of primer and cement. All fire stop and roof flashing used with this system must be UL listed material. Acceptability under Canadian standard CAN/CSA B149 is dependent upon full compliance with all installation instructions. Under this standard, it is recommended that the vent system be checked once a year by qualified service personnel.

The authority having jurisdiction (gas inspection authority, municipal building department, fire department, etc) should be consulted before installation to determine the need to obtain a permit.

*IPEX System 636™ is a trademark of IPEX Inc.

Consignes spéciales pour l’installation de ventilation au Canada

L’installation faite au Canada doit se conformer aux exigences du code CAN/CSA B149--2010. Ce systême de ventillation doit se composer de tuyaux, raccords, ciments et apprêts conformes au ULC S636. La tuyauterie de ventillation des gaz, ses accessoires, le terminal concentrique mural ainsi que l’ensemble du drain de condensat extérieur ont été certifiés ULCS 636 pour l’application des composantes Royal Pipe, IPEX PVC qui sont certifiées à ce standard. Au Canada, l’apprêt et le ciment doivent être du même fabricant quele système d’évacuation. L’apprêt GVS-65 (Purple) et le ciment-solvant GVS-65 doivent être utilisé avec les Royal Pipe. Système IPEX 636, apprêt PVC/CPVC, Purple pour évacuation des gaz de combustion et système IPEX 636(1)t, ciment PVC pour évacuation des gaz de combustion, coté classe IIA, 65 deg C. doivent être utilisés avec le système d’évacuation IPEX 636 – Ne pas combiner l ’apprêt et le ciment d’un manufacturier avec un système d’évacuation d’un manufacturier différent.

Bien suivre les indications du manufacturier lors de l’utilisation de l’apprêt et du ciment et ne pas utiliser ceux-ci si la date d’expiration est atteinte.

L’opération sécuritaire, tel que définit par ULC S636, du système de ventilation est basé sur les instructions d’installation suivantes, ainsi que l’usage approprié de l’apprêt et ciment. Tout arrêt feu et solin de toit utilisés avec ce système doivent être des matériaux listés UL. L’acceptation du standard Canadien CAN/CSA B149 est directement relié à l’installation conforme aux instructions cihaut mentionnées. Le standard Canadien recommande l’ inspection par un personnel qualifié et ce, une fois par année.

Les autorité es ayant juridiction (inspecteurs de gas, inspecteurs en bâtiments, département des incendies, etc) devraient être consultées avant l’installation afin de déterminer si un permis est requis.

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon monoxide poisoning or death.

The following steps shall be followed for each appliance connected to the venting system being placed into operation, while all other appliances connected to the venting system are not in operation:

1. Seal any unused openings in venting system.

2. Inspect the venting system for proper size and horizontal pitch, as required in the National Fuel Gas Code, NFPA 54/ANSI Z223.1--2009 and these instructions. In Canada, refer to CAN/CSA-B149.1--2010. Determine that there is no blockage or restriction, leakage, corrosion and other deficiencies, which could cause an unsafe condition.

3. As far as practical, close all building doors and windows and all doors between the space in which the appliance(s) connected to the venting system are located and other spaces of the building.

4. Close fireplace dampers.

5. Turn on clothes dryers and any appliance not connected to the venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they are operating at maximum speed. Do not operate a summer exhaust fan.

6. Follow the lighting instructions. Place the appliance being inspected into operation. Adjust the thermostat so appliance is operating continuously.

7. Test for spillage from draft hood equipped appliances at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or candle.

8. If improper venting is observed during any of the above tests, the venting system must be corrected in accordance with the National Fuel Gas Code, NFPA 54/ANSI Z223.1--2009. In Canada, refer to CAN/ CSA--B149.1--2010.

9. After it has been determined that each appliance connected to the venting system properly vents when tested as outlined above, return doors, windows, exhaust fans, fireplace dampers and any other gas--fired burning appliance to their previous conditions of use.

General

If this furnace replaces a furnace that was connected to a vent system or chimney, the vent or vent connectors of other remaining appliances may need to be re--sized. Vent systems or vent connectors of other appliances must be sized to the minimum size as determined using appropriate table found in the current edition of National Fuel Gas Code NFPA 54/ANSI Z--223.1. In Canada, refer to CAN/CSA--B149.1.

An abandoned masonry chimney may be used as a raceway for properly insulated and supported combustion--air (when applicable) and vent pipes. Each furnace must have its own set of combustion--air and vent pipes and be terminated individually, as shown in Fig. 46 for Direct Vent (2--Pipe) system or Fig. 47 for ventilated combustion air option.

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A furnace shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel.

Other gas appliances with their own venting system may also use the abandoned chimney as a raceway providing it is permitted by local code, the current edition of the National Fuel Gas Code and the vent or liner manufacturer’s installation instructions. Care must be taken to prevent the exhaust gases from one appliance from contaminating the combustion air of other gas appliances.

Do not take combustion air from inside the chimney when using ventilated combustion air or single pipe vent option.

These furnaces can be vented as either direct vent furnace or as ventilated combustion air system. Each type of venting system is described below. Common venting between furnaces or other appliances prohibited.

Materials

U.S.A.

Combustion air and vent pipe, fittings, primers, and solvents must conform to American National Standards Institute (ANSI) standards and American Society for Testing and Materials (ASTM) standards. See Table 11 for approved materials for use in the U.S.A.

Canada

Special Venting Requirements for Installations in Canada Installation in Canada must conform to the requirements of CAN/CSA B149 code. Vent systems must be composed of pipe, fittings, cements, and primers listed to ULC S636.

Ven ti ng Systems

A factory accessory KGAVT vent termination kit must be used for all direct vent terminations. Termination kits are available for 2--in. or 3--in. pipe. See Table 10 for available options.

Table 10 – Vent Termination Kit for Direct Vent (2--pipe)

Systems

DIRECT VENT

(2 --- PIPE)

TERMINATION KIT

2 --- i n . (5 1 m m )

Concentric Vent Kit

3 --- i n . (7 6 m m )

Concentric Vent Kit

2 --- i n . (5 1 m m )

Termination Bracket

Kit

3 --- i n . (7 6 m m )

Termination Bracket

Kit

TERMINATION

SYSTEM

Single Penetration of

Wall or Roof

Single Penetration of

wall or Roof

2 -- -Pipe Termin ation

System

2 -- -Pipe Termin ation

System

Direct Vent / 2-Pipe System

In a direct-vent (2-pipe) system, all air for combustion is taken directly from outdoor atmosphere, and all flue products are discharged to outdoor atmosphere. Combustion-air and vent pipes must terminate together in the same atmospheric pressure zone, either through the roof or a sidewall (roof termination preferred). A factory accessory vent termination kit MUST be used in a direct vent (2-pipe) system. See Fig. 44 for required clearances.

Ventilated Combustion Air Systems

In a ventilated combustion air option, the vent terminates and discharges the flue products directly to the outdoors similar to a direct vent system. See Fig. 45 for required clearances.

All air for combustion is piped directly to the furnace from a space that is well ventilated with outdoor air (such as an attic or crawl space) and the space is well isolated from the living space or garage. Combustion air requirements for this option are the same as the requirements for providing outside air for combustion for a single pipe vent system. Refer to the “Air For Combustion and Ventilation Section.

Provisions for adequate combustion, ventilation, and dilution air must be provided in accordance with:

DIAM. OF COMBUSTION AIR AND VENT

PIPES --- IN. (mm)

1, 1 --- 1/2, 2, or 2 ---1/2

(24, 36, 51, 64 mm)

2---1/2, 3 or 4

(64, 76, 102 mm)

1, 1 --- 1/2 or 2

(25, 36, 51 mm)

2---1/2, 3 or 4

(64, 76, 102 mm)

U.S.A. Installations: Section 9.3 NFPA 54/ANSI Z223.1-2009, Air for Combustion and Ventilation and applicable provisions of the local building codes.

Canadian Installations: Part 8 of CAN/CSA-B149.1-10. Venting Systems and Air Supply for Appliances and all authorities having jurisdiction.

Locating the Vent Termination

General

NOTE: Termination Requirements for the Provinces of Alberta and Saskatchewan are located at the end of this section.

Combustion--air (direct vent/2--pipe system only) and vent pipe must terminate outside structure, either through sidewall or roof.

For vent termination clearance, refer to Fig. 44 for Direct Vent/2--Pipe system and Fig. 45 for Non--direct Vent/1--Pipe system. For exterior termination arrangements, refer to Fig. 46 for Direct Vent/2--Pipe system and Fig. 47 for Non-- Direct/1--Pipe system.

Roof termination is preferred since it is less susceptible to damage or contamination, and it has less visible vent vapors. Sidewall terminations require sealing or shielding of building surfaces with a corrosive resistance material due to corrosive combustion products of vent system.

NOTE: (Direct Vent/2--Pipe system ONLY) A factory accessory termination kit MUST be used. See Table 10 for availableoptions.

When determining appropriate location for termination, consider the following guidelines:

1. Comply with all clearance requirements stated in Fig. 44 or Fig. 45 per application.

2. Termination or termination kit should be positioned where vent vapors will not damage plants/shrubs or air conditioning equipment.

3. Termination or termination kit should be positioned so that it will not be affected by wind eddy, such as inside building corners, nor by recirculation of flue gases, airborne leaves, or light snow.

4. Termination ortermination kit should be positioned where it will not be damaged by or subjected to foreign objects such as stones, balls, etc.

5. Termination or termination kit should be positioned where vent vapors are not objectionable.

Direct Vent / 2-Pipe System

Direct vent (2--pipe) vent and combustion air pipes must terminate outside the structure. Follow all clearances as shown Fig. 44. Allowable vent and combustion air terminations are shown in Fig.

46.

Ventilated Combustion Air

The vent pipe for a Ventilated Combustion Air System must terminate outdoors. Follow all vent termination clearances shown in Fig. 45. Allowable vent terminations are shown in Fig. 47. The combustion air pipe terminates in a well--ventilated attic or crawl space. Follow the clearances as shown in Fig. 49. When the furnace is installed in a well ventilated attic or crawlspace, install the combustion air pipe as shown in Fig. .43

The combustion air pipe cannot terminate in attics or crawl spaces that use ventilation fans designed to operate in the heating season. If ventilation fans are present in these areas, the combustion air pipe must terminate outdoors as a Direct Vent System.

Termination Requirements for the Provinces of Alberta and Saskatchewan

The Provinces of Alberta and Saskatchewan require a minimum unobstructed distance of 4 ft. (1.2 M) from the foundation to the property line of the adjacent lot for vent termination of any appliance with an input over 35,000 btuh. If there is less than 4 ft.

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(1.2 M) of unobstructed distance to the property line of the adjacent lot, no type of vent termination is permitted for appliances with inputs greater than 35,000 btuh.

There are no additional restrictions on unobstructed distances greater than 8 ft. (2.4 M). All single, two-pipe and concentric vents may be used, providing all other Code and manufacturer’s requirements in these instructions are adhered to. Refer to the appropriate Vent Termination section above for locating the vent termination

If the unobstructed distance from the foundation to the property line of the adjacent lot is no less than 4 ft. (1.2 M) and no greater than 8 ft. (2.4 M), it will be necessary to re-direct the flue gas plume. In this situation, a concentric vent kit cannot be used. A 2-pipe termination (or single pipe termination when permitted) that re-directs the flue gas away by use of an elbow or tee, certified to ULC S636 from the adjacent property line must be used. See Fig.

48. The concentric vent kit currently cannot be modified to attach an

elbow to the vent portion of the rain cap. A tee attached to the rain cap could potentially direct the flue gas plume toward the intake air

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stream and contaminate the incoming combustion air for the furnace.

Refer to Fig. 48 for terminations approved for use in Alberta and Saskatchewan.

Size the Vent and Combustion Air Pipes

General

Furnace combustion air and vent pipe connections are sized for 2-in. (51 mm) pipe. Any pipe diameter change should be made outside furnace casing in vertical pipe. Any change is diameter to the pipe must be made as close to the furnace as reasonably possible.

The Maximum Vent Length for the vent and combustion air pipe (when used) is determined from the Maximum Equivalent Vent Length in Table 13 or 15, minus the number of fittings multiplied by the deduction for each type of fitting used from Table 14.

The measured length of pipe used in a single or 2--pipe termination is included in the total vent length. Include a deduction for a Tee when used for Alberta and Saskatchewan terminations. Concentric vent terminations, pipe lengths or elbows do not require a deduction from the Maximum Equivalent Vent Length.

1. Measure the individual distance from the furnace to the termination for each pipe.

2. Select a Maximum Equivalent Vent Length (MEVL) longer than the measured distance of the individual vent and combustion air connections to the vent termination.

3. Count the number of elbows for each pipe.

4. For each pipe, multiply the number of elbows by the equivalent length for the type of elbow used. Record the equivalent length of all the elbows for each pipe.

5. If a Tee is used on the termination, record the equivalent length of the Tee used.

6. Record the equivalent length of the termination to be used.

7. Subtract the equivalent lengths of the fittings and terminations from the Maximum Equivalent Vent Length.

8. If the Maximum Vent Length calculated is longer than the individual measured length of the vent pipe and combustion air pipe, then the diameter of pipe selected may be used.

9. If the Maximum Vent Length calculated is shorter than the individual measured length of either the vent pipe or the combustion air pipe, recalculate the Maximum Vent Length using the next larger diameter pipe.

NOTE: The vent pipe and combustion air pipe must be the same diameter.

NOTE: If the Maximum Vent Length for diameter of the pipe selected is longer than the measured length and the equivalent

length of all the fitting and terminations, recalculate using the next smaller diameter. If the recalculated Maximum Vent Length is longer than the measured length of the vent pipe and combustion air pipe, then that diameter of pipe selected may be used.

When installing vent systems of short pipe lengths, use the smallest allowable pipe diameter. Do not use pipe size greater than required or incomplete combustion, flame disturbance, or flame sense lockout may occur.

Combustion Air and Vent Piping Insulation Guidelines

NOTE: Use closed cell, neoprene insulation or equivalent.

The vent pipe may pass through unconditioned areas. The amount of exposed pipe allowed is shown in Table 12.

1. Using winter design temperature (used in load calculations), find appropriate temperature for your application and furnace model.

2. Determine the amount of total and exposed vent pipe.

3. Determine required insulation thickness for exposed pipe length(s).

4. When combustion air inlet piping is installed above a suspended ceiling, the pipe MUST be insulated with moisture resistant insulation such as Armaflex or other equivalent type of insulation.

5. Insulate combustion air inlet piping when run in warm, humid spaces.

6. Install the insulation per the insulation manufacturer’s installation instructions.

NOTE: Pipe length (ft. / M) specified for maximum pipe lengths located in unconditioned spaces cannot exceed total allowable pipe length as calculated from Table 13 or 15.

Configure the Furnace

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

To route the vent pipe and combustion air pipe through the furnace, the manufacturer supplied kit must be used. Failure to properly seal the blower compartment from the furnace vestibule could result in the circulation of carbon monoxide throughout the structure. The vent pipe and combustion air pipe must be a continuous pipe while passing through the blower compartment. Seals supplied in this kit must be installed per the instructions provided. Follow all procedures outlined in these instructions.

Install the Vent and Combustion Air Pipe

With the furnace installed in the required position, remove the desired knockouts from the casing. It will be necessary to remove one knockout for the vent pipe and the other knockout for the combustion air connection. (See Fig. 11.)

Use a flat blade screwdriver and tap on the knockout on opposite sides, where the knockout meets the casing. Fold the knockout down with duct pliers and work the knockout back and forth until it is removed. Trim any excess metal from the knockout with tin snips.

The vent elbow can be rotated to the required location on the casing if necessary. See Fig. 37. To rotate the vent elbow:

1. Loosen the clamp on the inlet of the vent elbow attached to the inducer.

Page 41

2. Rotate the vent elbow to the required position. There are rounded notches in the vent elbow to align it with the inducer housing for each orientation.

3. Tighten the clamp around the vent elbow. Torque the clamp to 15 lb--in. See Fig. 38--41.

Installing the Vent Pipe Adapter and Combustion Air Pipe Adapter

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or death.

NOTE: The rubber coupling that attaches to the vent pipe adapter must be used. The adapter seals the vent pipe to the casing and reduces the strain on the vent elbow attached to the inducer.

1. Apply the gaskets to the vent pipe and combustion air pipe adapters. See Fig. 36.

NOTE: The vent pipe adapter and the combustion air pipe adapter have the same ID however, the combustion air pipe adapter has a pipe stop at the end.

2. Align the screw holes in the plastic vent pipe adapter with the dimples in the casing.

3. Pilot drill the screw holes for the adapter in the casing and attach the vent pipe adapter to the furnace with sheet metal screws

4. Slide the end of the rubber vent coupling with notches in it over the standoffs on the vent pipe adapter.

5. Insert a length of vent pipe through the coupling into the outlet of the vent elbow.

6. Tighten the clamp around the outlet of the vent elbow. Torque the clamp to 15 lb--in.

Install the remaining vent and combustion air pipes as shown below. It is recommended that all pipes be cut, prepared, and preassembled before permanently cementing any joint.

1. Working from furnace to outside, cut pipe to required length(s).

2. Deburr inside and outside of pipe.

3. Chamfer outside edge of pipe for better distribution of primer and cement.

4. Clean and dry all surfaces to be joined.

5. Check dry fit of pipe and mark insertion depth on pipe.

6. Insert the vent pipe into the vent elbow.

7. Torque clamp on vent elbow 15 lb--in.

8. Torque clamp on vent coupling 15 lb--in.

9. Insert the combustion air pipe into the adapter.

10. Pilot drill a screw hole through the adapter into the combustion air pipe and secure the pipe to the adapter with sheet metal screws.

11. Seal around the combustion air pipe with silicone or foil tape.

12. After pipes have been cut and preassembled, apply generous layer of cement primer to pipe fitting socket and end of pipe

to insertion mark. Quickly apply approved cement to end of pipe and fitting socket (over primer). Apply cement in a light, uniform coat on inside of socket to prevent buildup of excess cement. Apply second coat.

13. While cement is still wet, twist pipe into socket with 1/4--in. turn. Be sure pipe is fully inserted into fitting socket.

14. Wipe excess cement from joint. A continuous bead of cement will be visible around perimeter of a properly made joint.

15. Handle pipe joints carefully until cement sets.

16. Horizontal portions of the venting system shall be supported to prevent sagging. Support combustion air piping and vent piping a minimum of every 5 ft. (1.5M)[3 ft. (.91M) for SDR--21 or --26 PVC] using perforated metal hanging strap or commercially available hangars designed to support plastic pipe.

17. Prevent condensate from accumulating in the pipes by sloping the combustion air piping and vent piping downward towards furnace a minimum of 1/4-in. per linear ft. with no sags between hangers.

18. Complete the vent and combustion air pipe installation by connecting the concentric vent or by installing the required termination elbows as shown in Fig. 46, 47 and 48. For Ventilated Combustion Air Termination, See Fig. 49

19. Use appropriate methods to seal openings where combustion air pipe and vent pipe pass through roof or sidewall.

Optional Installation of the Vent Pipe

This option provides a disconnect point for the vent pipe. The vent pipe must be cemented to the plastic vent pipe adapter to maintain a sealed vestibule. See Fig. 42.

1. Insert a length of vent pipe through the casing into the outlet of the vent elbow.

2. Slide the plastic vent pipe adapter over the length of the vent pipe down to the furnace casing. Mark the pipe where it is flush with the outlet of the adapter.

3. Remove the pipe from the furnace and the adapter and cut off any excess pipe.

4. Clean and prime the end of the pipe that is flush with the vent adapter with a primer that is appropriate for the type of pipe being used.

5. Re--insert the pipe through the casing into the vent elbow.

6. Tighten the clamp around the outlet of the vent elbow. Torque the clamp to 15 lb--in.

7. Apply cement to the end of the pipe and to the inside of the plastic vent adapter.

8. Slide the adapter over the vent pipe and align the screw holes in the adapter with the dimples in the furnace casing.

9. Pilot drill 1/8--in. screw holes for the adapter in the casing and secure the adapter to the furnace with sheet metal screws.

10. Loosen the clamps on the rubber vent coupling.

11. Slide the end of the coupling with notches in it over the standoffs in the vent pipe adapter.

12. Tighten the clamp of the coupling over the vent pipe adapter. Torque the lower clamp around the vent pipe adapter to 15 lb--in.

13. Pilot drill a 1/8--in. hole in the combustion air pipe adapter.

14. Complete the vent and combustion air pipe as shown in “Install the Vent and Combustion Air Pipe”

Installing the Vent Termination

Roof Terminations

A roof termination of any type will require a 4-in. (102 mm) flashing for a 2 inch (51 mm) concentric vent or a 5--in. diameter (127 mm) flashing for a 3-inch (76 mm) concentric vent kit. For

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Page 42

two-pipe or single pipe vent systems, a flashing for each pipe of the required diameter will be necessary.

It is recommended that the flashing be installed by a roofer or competent professional prior to installing the concentric vent. The terminations can be installed on a flat or pitched roof.

Concentric Vent

Single or multiple concentric vent must be installed as shown in Fig. 46. Maintain the required separation distance between vents or pairs of vents as shown in Fig. 46 and all clearance shown in Fig. 44.

Cut one 4--in. (102 mm) diameter hole for 2--in. (51 mm) kit, or one 5--in. (127 mm) diameter hole for 3--in. (76 mm) kit in the desired location.

Loosely assemble concentric vent/combustion air termination components together using instructions in kit.

Slide assembled kit with rain shield REMOVED through hole in wall or roof flashing.

NOTE: Do not allow insulation or other materials to accumulate inside of pipe assembly when installing it through hole.

987MA

Disassemble loose pipe fittings. Clean and cement using same procedures as used for system piping.

Two--Pipe and Single--Pipe Terminations

Single and two pipe vent must be installed as shown in Fig. 46 and

47. Maintain the required separation distance between vents or pairs of vents as shown in Fig. 46 and 47. and all clearance shown in Fig. 44 and 45.

Cut the required number of holes in the roof or sidewall for vent and (when used) combustion air pipes. Sidewall holes for two-pipe vent terminations should be side-by-side, allowing space between the pipes for the elbows to fit on the pipes.

Holes in the roof for two pipe terminations should be spaced no more than 18 in. (457 mm) apart.

Termination elbows will be installed after the vent and (if used) combustion air pipe is installed.

Sidewall Terminations Concentric Vent Termination

Determine an appropriate location for termination kit using the guidelines provided in section “Locating The Vent Termination” in this instruction.

1. Cut one 4--in. diameter hole for 2--in. kit, or one 5--in. diameter hole for 3--in. kit.

2. Loosely assemble concentric vent/combustion air termination components together using instructions in kit.

3. Slide assembled kit with rain shield REMOVED through hole.

NOTE: Do not allow insulation or other materials to accumulate inside of pipe assembly when installing it through hole.

4. Locate assembly through sidewall with rain shield positioned no more than 1--in. (25 mm) from wall as shown in Fig. 46.

5. Disassemble loose pipe fittings. Clean and cement using same procedures as used for system piping.

Direct Vent (2--pipe) Termination

Determine an appropriate location for termination kit using the guidelines provided in section “Locating The Vent Termination” in this instruction.

1. Cut 2 holes, 1 for each pipe, of appropriate size for pipe size being used.

2. Loosely install elbow in bracket and place assembly on combustion--air pipe.

3. Install bracket as shown in Fig. 46 and 48.

NOTE: For applications using vent pipe option indicated by dashed lines in Fig. 46 and 47, rotate vent elbow 90_ from position.

4. Disassemble loose pipe fittings. Clean and cement using same procedures as used for system piping.

For ventilated Combustion Air Terminations, terminate as shown in Fig. 47.

(Direct Vent / 2-Pipe System ONLY)

When 2 or more furnaces are vented near each other, 2 vent terminations may be installed as shown in Fig. 46, but next vent termination must be at least 36 in. (914 mm) away from first 2 terminations. It is important that vent terminations be made as showninFig.46toavoidrecirculationoffluegases.

Inducer Outlet Restrictor

The loose parts bag may contain an inducer outlet restrictor. The outlet restrictor is NOT used on these furnaces. Discard restrictor.

Table 11 – Approved Combustion-Air and Vent Pipe, Fitting and Cement Materials (U.S.A. Installations)

ASTM SPECIFICATION

(MARKED ON MATERIAL)

D1527 ABS Pipe — — S c h e d u l e --- 4 0 D1785 PVC Pipe — — S c h e d u l e --- 4 0 D2235 For ABS — — Solvent Cement For ABS D2241 PVC Pipe — — S D R --- 2 1 & S D R --- 2 6 D2466 PVC — Fittings — Sc h e d u l e --- 4 0 D2468 ABS — Fittings — S c h e d u l e --- 4 0 D2564 For PVC — — Solvent Cement For PVC D2661 ABS Pipe Fittings — DWV at Schedule---40 IPS sizes D2665 PVC Pipe Fittings — DWV

F438 CPVC — Fittings — S c h e d u l e --- 4 0 F441 CPVC Pipe — — Sc h e d u l e --- 4 0 F442 CPVC Pipe — — SDR F493 For CP VC — — Solvent Cement For C PVC

F628 ABS Pipe — —

F656 For PVC — — Primer For PVC F891 PVC Pipe — — Cellular Core Schedule - -- 40 & DWV

MATERIAL PIPE FITTINGS

SOLVENT CEMENT

AND PRIMERS

DESCRIPTION

Cellular Core DWV at Schedule---40

IPS sizes

Page 43

Modulating

Furnace

Max Heat

Input

60000

Winter

Design Temp

°F(°C)

20 (-10)

0 (-20)

-20 (-30)

-40 (-40)

Table 12 – Maximum Allowable Exposed Vent Lengths Insulation Table -- Ft. / M

Maximum Length of Uninsulated and Insulated Vent Pipe-Ft (M)

No Insulatio n 3/8-in. (9.5 mm) 1/2-in. (12.7 mm)

Pipe Length

in Ft. & M

Ft. 34.0 29.0 28.0 23.0 N/A 55.0 88.0 79.0 69.0 N/A 55.0 104.0 93.0 81.0 N/A

M 10.4 8.8 8.5 7.0 N/A 16.8 26.8 24.1 21.0 N/A 16.8 31.7 28.3 24.7 N/A

Ft. 14.0 9.0 7.0 0.0 N/A 55.0 49.0 43.0 34.0 N/A 55.0 60.0 52.0 42.0 N/A

M 4.3 2.7 2.1 0.0 N/A 16.8 14.9 13.1 10.4 N/A 16.8 18.3 15.8 12.8 N/A

Ft. 5.0 0.0 0.0 0.0 N/A 41.0 32.0 26.0 18.0 N/A 50.0 40.0 33.0 24.0 N/A

M 1.5 0.0 0.0 0.0 N/A 12.5 9.8 7.9 5.5 N/A 15.2 12.2 10.1 7.3 N/A

Ft. 0.0 0.0 0.0 0.0 N/A 30.0 21.0 16.0 8.0 N/A 37.0 28.0 22.0 13.0 N/A

M 0.0 0.0 0.0 0.0 N/A 9.1 6.4 4.9 2.4 N/A 11.3 8.5 6.7 4.0 N/A

Pipe Diameter-in. (mm) Pipe Diameter-in. (mm) Pipe Diameter-in. (mm)

1.5 2.0 2.5 3.0 4.0 1.5 2.0 2.5 3.0 4.0 1.5 2.0 2.5 3.0 4.0

(38) (51) (64) (76) (102) (38) (51) (64) (76) (102) (38) (51) (64) (76) (102)

20 (-10)

0 (-20)

80000

-20 (-30)

-40 (-40)

20 (-10)

0 (-20)

100000

-20 (-30)

-40 (-40)

20 (-10)

0 (-20)

120000

-20 (-30)

-40 (-40)

* Pipe length (ft) specified for maximum pipe lengths located in unconditioned spaces. Pipes located in unconditioned space cannot exceed total allowable pipe length calculated from Table 13 or 15.

† Insulation thickness based on R value of 3.5 per in.

Ft. 35.0 39.0 39.0 33.0 25.0 35.0 118.0 107.0 92.0 76.0 35.0 130.0 125.0 109.0 90.0

M 10.7 11.9 11.9 10.1 7.6 10.7 36.0 32.6 28.0 23.2 10.7 39.6 38.1 33.2 27.4

Ft. 22.0 16.0 14.0 7.0 0.0 35.0 69.0 60.0 49.0 35.0 35.0 83.0 72.0 60.0 45.0

M 6.7 4.9 4.3 2.1 0.0 10.7 21.0 18.3 14.9 10.7 10.7 25.3 21.9 18.3 13.7

Ft. 11.0 5.0 2.0 0.0 0.0 35.0 46.0 39.0 29.0 16.0 35.0 57.0 48.0 37.0 23.0

M 3.4 1.5 0.6 0.0 0.0 10.7 14.0 11.9 8.8 4.9 10.7 17.4 14.6 11.3 7.0

Ft. 4.0 0.0 0.0 0.0 0.0 35.0 33.0 26.0 17.0 4.0 35.0 41.0 34.0 24.0 11.0

M 1.2 0.0 0.0 0.0 0.0 10.7 10.1 7.9 5.2 1.2 10.7 12.5 10.4 7.3 3.4

Ft. N/A 47.0 47.0 41.0 32.0 N/A 50.0 110.0 112.0 93.0 N/A 50.0 110.0 132.0 110.0

M N/A 14.3 14.3 12.5 9.8 N/A 15.2 33.5 34.1 28.3 N/A 15.2 33.5 40.2 33.5

Ft. N/A 21.0 19.0 12.0 1.0 N/A 50.0 74.0 61.0 45.0 N/A 50.0 89.0 74.0 57.0

M N/A 6.4 5.8 3.7 0.3 N/ A 15.2 22.6 18.6 13.7 N/A 15.2 27.1 22.6 17.4

Ft. N/A 8.0 6.0 0.0 0.0 N/A 50.0 49.0 38.0 23.0 N/A 50.0 60.0 48.0 32.0

M N/A 2.4 1.8 0.0 0.0 N/ A 15.2 14.9 11.6 7.0 N/A 15.2 18.3 14.6 9.8

Ft. N/A 1.0 0.0 0.0 0.0 N/A 42.0 34.0 24.0 10.0 N/A 50.0 43.0 32.0 18.0

M N/A 0.3 0.0 0.0 0.0 N/ A 12.8 10.4 7.3 3.0 N/A 15.2 13.1 9.8 5.5

Ft. N/A N/A 15.0 49.0 40.0 N/A N/A 15.0 100.0 111.0 N/A N/A 15.0 100.0 131.0

M N/A N/A 4.6 14.9 12.2 N/A N/A 4.6 30.5 33.8 N/A N/A 4.6 30.5 39.9

Ft. N/A N/A 15.0 17.0 6.0 N/A N/A 15.0 75.0 57.0 N/A N/A 15.0 90.0 70.0

M N/A N/A 4.6 5.2 1.8 N/A N/A 4.6 22.9 17.4 N/A N/A 4.6 27.4 21.3

Ft. N/A N/A 10.0 2.0 0.0 N/A N/A 15.0 48.0 32.0 N/A N/A 15.0 59.0 42.0

M N/A N/A 3.0 0.6 0.0 N/A N/A 4.6 14.6 9.8 N/A N/A 4.6 18.0 12.8

Ft. N/A N/A 1.0 0.0 0.0 N/A N/A 15.0 32.0 17.0 N/A N/ A 15.0 41.0 25.0

M N/A N/A 0.3 0.0 0.0 N/A N/A 4.6 9.8 5.2 N/A N/A 4.6 12.5 7.6

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Page 44

NOTE: Maximum Equivalent Vent Length (MEVL) does NOT include elbows or terminations. Use Table 14 - Deductions from

Maximum Equivalent Vent Length to determine allowable vent length for each application.

Altitude

FT (M)

0 to 2000 (0 to 610)

2001 to 3000

(610 to 914)

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3001 to 4000 (914 to 1219)

4001 to 4500

(1219 to

1370)

* See notes at end of venting tables. *See Table 15 for altitudes over 4500 ft. (1370 M)

Unit Size

BTU/Hr

60,000 55 (16.8) 135 (41.1) 235 (71.6) 265 (80.8) NA

80,000 35 (10.7) 130 (39.6) 175 (53.3) 235 (71.6) 265 (80.8)

100,000 NA 50 (15.2) 110 (33.5) 235 (71.6) 265 (80.8)

120,000 NA NA 15 (4.6) 100 (30.5) 250 (76.2)

60,000 45 (13.7) 127 (38.7) 222 (67.7) 250 (76.2) NA

80,000 30 (9.1) 90 (27.4) 165 (50.3) 222 (67.7) 249 (75.9)

100,000 NA 40 (12.2) 104 (31.7) 223 (68.0) 250 (76.2)

120,000 NA NA 11 (3.4) 93 (28.3) 237 (72.2)

60,000 40 (12.2) 119 (36.3) 210 (64.0) 235 (71.6) NA

80,000 25 (7.6) 85 (25.9) 155 (47.2) 210 (64.0) 232 (70.7)

100,000 NA 40 (12.2) 98 (29.9) 211 (64.3) 236 (71.9)

120,000 NA NA 8 (2.4) 86 (26.2) 224 (68.3)

60,000 35 (10.7) 115 (35.1) 204 (62.2) 228 (69.5) NA

80,000 23 (7.0) 85 (25.9) 150 (45.7) 202 (61.6) 224 (68.3)

100,000 NA 40 (12.2) 94 (28.7) 205 (62.5) 229 (69.8)

120,000 NA NA NA 83 (25.3) 217 (66.1)

Table 13 – Maximum Equivalent Vent Length -- Ft. (M)

0 to 4500 Ft. (0 to 1370 M) Altitude

DIRECT VENT (2-PIPE) AND VENTILATED COMBUSTION AIR ONLY

Vent Pipe Diameter (in.)

1-1/2 2 2-1/2 3 4

Table 14 – Deductions from Maximum Equivalent Vent Length -- Ft. (M)

Pipe Diameter (in): 1-1/2 2 2-1/2 3* 4*

Mitered 90º Elbow 8 (2.4) 8 (2.4) 8 (2.4) NA NA NA NA

Medium Radius 90º Elbow 5 (1.5) 5 (1.5) 5 (1.5) NA NA NA NA

Long Radius 90º Elbow 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9)

Mitered 45º Elbow 4 (1.2) 4 (1.2) 4 (1.2) NA NA NA NA

Medium Radius 45º Elbow 2.5 (0.8) 2.5 (0.8) 2.5 (0.8) NA NA NA NA

Long Radius 45º Elbow 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5)

Tee 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9)

* Note: 3 --- and 4 ---in. Vent pipe systems require long radiu s elbows.

Venting System Length Calculations

The maximum length for each vent pipe (inlet or exhaust) equals the Maximum Equivalent Vent Length (MEVL) from Table 13 or Table 15 minus the number of elbows multiplied by the deduction for each elbow in Table 14.

Standard vent terminations and concentric vent terminations count for zero deductions.

Example

A direct--vent 60,000 Btuh furnace installed at 2100 ft. (640 m) with 2--in.(51 mm) Vent piping. Venting system includes, FOR EACH PIPE, (3) 90_ long radius elbows, (2) 45_ long radius elbows and a concentric vent kit.

Maximum Equivalent Vent Length = 127 ft. (From Table 13)

Deduct (3) 90 long radius 3 x 3 ft. = - 9 ft. (From Table 14) Deduct (2) 45 long radius 2 x 1.5 ft. = - 3 ft. (From Table 14)

Maximum Vent Length = 115 ft. For EACH vent or inlet pipe

Page 45

NOTE: Maximum Equivalent Vent Length (MEVL) does NOT include elbows or terminations. Use Table 14 - Deductions from

Maximum Equivalent Vent Length to determine allowable vent length for each application.

Table 15 – Maximum Equivalent Vent Length -- Ft. (M)

4501 to 10,000 Ft. (0 to 1370 M) Altitude

Altitude

FT (M)

4501 to 5000

(1370 to

1524)

5001 to 6000

(1524 to

1829)

6001 to 7000

(1829 to

2134)

7001 to 8000

(2134 to

2438)

8001 to 9000

(2438 to

2743)

9001 to

10,000

(2743 to

3048)

Unit Size

1-1/2 2 2-1/2 3 4

60,000 35 (10.7) 111 (33.8) 198 (60.4) 221 (67.4) NA

80,000 23 (7.0) 85 (25.9) 146 (44.5) 195 (59.4) 216 (65.8)

100,000 NA 40 (12.2) 91 (27.7) 200 (61.0) 222 (67.7)

120,000 NA NA NA 80 (24.4) 211 (64.3)

60,000 37 (11.3) 103 (31.4) 186 (56.7) 207 (63.1) NA

80,000 22 (6.7) 76 (23.2) 137 (41.8) 183 (55.8) 200 (61.0)

100,000 NA 33 (10.1) 85 (25.9) 188 (57.3) 208 (63.4)

120,000 NA NA NA 74 (22.6) 199 (60.7)

60,000 35 (10.7) 96 (29.3) 174 (53.0) 194 (59.1) NA

80,000 20 (6.1) 71 (21.6) 120 (36.6) 171 (52.1) 185 (56.4)

100,000 NA 31 (9.4) 79 (24.1) 178 (54.3) 195 (59.4)

120,000 NA NA NA 68 (20.7) 187 (57.0)

60,000 32 (9.8) 89 (27.1) 163 (49.7) 181 (55.2) NA

80,000 18 (5.5) 66 (20.1) 120 (36.6) 159 (48.5) 170 (51.8)

100,000 NA 29 (8.8) 73 (22.3) 167 (50.9) 182 (55.5)

120,000 NA NA NA 62 (18.9) 175 (53.3)

60,000 30 (9.1) 82 (25.0) 152 (46.3) 168 (51.2) NA

80,000 17 (5.2) 62 (18.9) 111 (33.8) 148 (45.1) 156 (47.5)

100,000 NA 27 (8.2) 67 (20.4) 157 (47.9) 170 (51.8)

120,000 NA NA NA 56 (17.1) 164 (50.0)

60,000 27 (8.2) 76 (23.2) 142 (43.3) 156 (47.5) NA

80,000 15 (4.6) 57 (17.4) 103 (31.4) 137 (41.8) 142 (43.3)

100,000 NA 24 (7.3) 62 (18.9) 147 (44.8) 157 (47.9)

120,000 NA NA NA 51 (15.5) 153 (46.6)

DIRECT VENT (2-PIPE) AND VENTILATED COMBUSTION AIR ONLY

Vent Pipe Diameter

987MA

Notes:

1. 3-- - and 4 ---in. Vent pipe systems require lon g radius elbows.

2. Vent sizing for C anadian installa tions over 4500 ft. (1370 M) above sea level are subject to acceptance by the local authorities having jurisdiction.

3. NA -- - Not allowed; pressure switch will not close, or flame disturbance may result.

4. Do not use pipe size greater than those specified in table or incomplete combustion, flame disturbance, or flame sense lockout may occur.

5. Size both the combustion --- air and vent pipe independently, then use the larger diameter for both pipes.

6. Assume the two 45_ elbows equal one 90_ elbow. Wide radius elbows are desirable and may be required in some cases.

7. Elbows and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.

8. The minimum pipe length is 5 ft. (1.5 M) for all application s.

9. Use 3 ---in. (76 mm) diameter vent termination kit for installations requiring 4 --- in. (102 mm) diameter pipe.

Page 46

987MA

Attach gaskets to vent pipe and combustion air adapters.

Fig. 36 -- Vent Coupling and Adapter with Gaskets

Vent Coupling and Adapter

VENT ELBOW CLAMP TORQUE 15 LB-IN.

A11314

MODULATING INDUCER ASSEMBLY

INDUCER OUTLET

Fig. 37 -- Inducer Vent Elbow

(Appearance May Vary)

VENT PIPE CLAMP TORQUE 15 LB-IN.

VENT ELBOW

A11286

Page 47

Any other unused

knockout may be used

for combustion air

connection.

Any other unused

knockout may be used

Rotate vent elbow to

required position.

A11309

for combustion air

connection.

Rotate vent elbow to

required position.

A11308

Any other unused

knockout may be used

for combustion air

connection.

A11310

Attach vent pipe adapter with gasket to furnace casing.

Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.

Slide vent pipe through adapter and coupling into vent elbow.

Insert vent pipe into vent elbow.

Torque all clamps 15 lb.-in.

Attach combustion air pipe adapter with gasket to furnace.

Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.

hole in adapter and secure with a #7 x 1/2-in sheet metal screw.

Fig. 38 -- Upflow Configurations

(Appearance May Vary)

987MA

A11399

Page 48

987MA

Rotate vent elbow to

required position.

Rotate vent elbow to

required position.

Any other unused

knockout may be used

for combustion air

connection.

A11311

A11312

A11313

Downflow Vertical

Requires Accessory Internal Vent Kit.

See Product Data for current kit number.

Attach vent pipe adapter with gasket to furnace casing.

Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.

Slide vent pipe through adapter and coupling into vent elbow.

Insert vent pipe into vent elbow.

Torque all clamps 15 lb.-in.

Attach combustion air pipe adapter with gasket to furnace.

Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.

hole in adapter and secure with a #7 x 1/2-in sheet metal screw.

Fig. 39 -- Downflow Configurations

(Appearance May Vary)

A11400

Page 49

HORIZONTAL LEFT VERTICAL VENT CONFIGURATION

HORIZONTAL LEFT RIGHT VENT CONFIGURATION*

*Requires Accessory Internal Vent Kit See Product Data for Current Kit Number

HORIZONTAL LEFT LEFT VENT CONFIGURATION

987MA

Attach vent pipe adapter with gasket to furnace casing.

Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.

Slide vent pipe through adapter and coupling into vent elbow.

Insert vent pipe into vent elbow.

Torque all clamps 15 lb.-in.

Attach combustion air pipe adapter with gasket to furnace.

Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.

hole in adapter and secure with a #7 x 1/2-in sheet metal screw.

A11340

Fig. 40 -- Horizontal Left

(Appearance May Vary)

Page 50

HORIZONTAL RIGHT -

987MA

VERTICAL VENT CONFIGURATION

HORIZONTAL RIGHT LEFT VENT CONFIGURATION* *Requires Internal Vent Kit See Product Data for Current Kit Number

HORIZONTAL RIGHT RIGHT VENT CONFIGURATION

Attach vent pipe adapter with gasket to furnace casing.

Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.

Slide vent pipe through adapter and coupling into vent elbow.

Insert vent pipe into vent elbow.

Torque all clamps 15 lb.-in.

Attach combustion air pipe adapter with gasket to furnace.

Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.

hole in adapter and secure with a #7 x 1/2-in sheet metal screw.

A11341

Fig. 41 -- Horizontal Right

(Appearance May Vary)

Page 51

VENT PIPE ADAPTER WITH GASKET INSTALLED ON FURNACE VENT PIPE IS CUT FLUSH WITH TOP OF ADAPTER.

ALIGN NOTCHES IN VENT PIPE COUPLING OVER STAND-OFF ON ADAPTER. TORQUE LOWER CLAMP 15 LB-IN. WHEN REMAINING VENT PIPE IS INSTALLED, TORQUE UPPER CLAMP TO 15 LB-IN.

987MA

VENT PIPE FLUSH WITH ADAPTER

Fig. 42 -- Vent Pipe Flush with Adaptor

Point elbow down towards back of furnace

VENT PIPE FLUSH SHOWING COUPLING

A11339

12” MINIMUM

256.0 mm

CASING SIDE ATTACHMENT COMBUSTION AIR PIPE (ATTIC OR CRAWLSPACE ONLY)

TOP PLATE ATTACHMENT COMBUSTION AIR PIPE (ATTIC OR CRAWLSPACE ONLY)

A11376

Fig. 43 -- Combustion Air Pipe Attachment

Page 52

987MA

Clearance Description Canadian Installation (1) U.S. Installation (2)

Item

Clearance above grade, veranda, porch, deck, bal-

cony or anticipated snow le vel

B Clearance to a window or door that may be opened

C Clearance to a permane ntly cl osed window

Vertical clearance to a ventilated soffit located above the terminal within a horizontal di stance of 2 feet (61

cm) from the centerline o f the terminal

E Clearance to an unventilated soff it F Clearance to a n outside corner

G Clearancetoaninsidecorner

Clearance to each side o f the cente rline extended above electrical meter or gas service regulator as-

sembly

I Clearance to service regulator vent outlet 3ft.(.9M)

Clearance to non--- mechanical air supply inlet to building or the combustion air inlet to any other appli-

ance

K Clearance to a mechanical air supply inlet 6ft.(1.8M) 3ft.(.9M)

L Clearance under a veranda, porch, deck, or balcony

Clearance to each side o f the cente rline extended above or below vent terminal of the furnace to a dryer

or water heater vent, or other appliance’s direct vent intake or exhaust

Clearance to the vent termi nal of a dryer vent, wa ter heater vent, or other applia nces direct ve nt intake or

exhaust

O Clearance from a plumbing vent stack 3ft.(.9M) 3ft.(.9M)

Clearance above paved sidewalk or paved driveway

located on public property

(1) In accordance with the current C A N / CSA B (2) In accordance with the current ANSI Z22 3.1.NFPA 54, National Fuel Gas Code Notes:

1. The vent forthis appliance shall not terminate:

a. Over public walkways; or

b. Near soffit vents of crawl space vents or oth er areas where condensate or vap or could create a nuisance o r hazard or property damage; o r

c. Where condensate vapor could cause damage orcould be detrimental to the operation of regulators,relief valves,or otherequipment.

2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion products of adjacent vents. Recirculation can cause poor combustio n, inlet condensate problems, and accelerated corrosion of the heat exchan gers.

3. Avoid v enting under a deck or large overhang. Recirculation could o ccur and cause performance or system problems.

149.1, Natural Gas and Propane Installation Code.

12 in. (305 mm). 18 in. (457 mm) above roof surface. 12 in. (305 mm)

12 in. (305 mm) for appliances > 10,000 Btuh (3kW) and </--- 100,000 Btuh (30 kW), 36 in. (914 mm) for appliances > 100,000 Btuh (30 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or C A N / CSA B149.1, clearances shall be in accordance with local installation codes and the requirements of the gas supplier and the manufacturer’s installation instructions.

3ft.(.9M)within15ft. (4.6 M) abovethemeter/ regulator assembly

12 in. (305 mm) for appliances > 10,000 Btuh(3kW) and </--- 100,000 Btuh (30 kW), 36 in. (914 mm) for appliances > 100,000 Btuh (30 kW)

12 in. (305 mm). Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides b eneath the f loor.

12 in. (305 mm) 12 in. (305 mm)

3ft.(.9M) 3ft.(.9M)

7 ft. (2.1 M). A vent shall not terminate above a sidewalk or paved driveway that is locate d betwee n two single family dwellings and serves both dwellings.

Fig. 44 -- Direct Vent Termination Clearance

9 in. (229 mm) for appliances > 10,000 Btuh (3kW) and </--- 50,000 Btuh (15 kW), 12 in. (305 mm) for appliances > 500,000 Btuh (15 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or C A N / CSA B149.1, clearances shall be in accordance with loca l installation codes and the requi rements of the gas supplier and the manufacturer’s installation instructions.

3ft.(.9M)within15ft. (4.6 M) abovethemeter/ regulator assembly

*3 ft. (.9 M) *For cl eara nces not specified in ANSI Z223 .1 /NFPA 54or C A N / CSA B149.1, clearances shall be in accordance wi th local i nstallati on codes and the requirements of the gas supplier and the manufa cturer’s installation instructions.

9 in. (229 mm) for appliances > 10,000 Btuh (3kW) and </--- 50,000 Btuh (15 kW), 12 in. (305 mm) for appliances > 500,000 Btuh (15 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or C A N / CSA B149.1, clearances shall be in accordance with loca l installation codes and the requi rements of the gas supplier and the manufacturer’s installation instructions.

For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B149.1, clearances shall be in accordance with loca l installation codes and the requi rements of the gas supplier and the manufacturer’s installation instructions.

A11046

Page 53

Item Clearance Description Canadian Installation (1) U.S. Installation (2)

Clearance above grade, veranda, porch, deck, bal-

cony or anticipated snow le vel

B Clearance to a window or door that may be opened

C Cle arance t o a pe rmanently close d windo w

Vertical clearance to a ventilated soffit located above the terminal within a horizontal di stance of 2 feet (61

cm) from the centerline of the te rminal

E Cl earance to an unventila ted soffit F Cleara nce to an outside corner G Clea rance to an inside corner

Clearance to each side o f the cente rline extended above electrical meter or gas service regulator as-

sembly

I Clearance to service regulator vent outlet 3ft.(.9M)

Clearance to non--- mechanical air supply inlet to building or the combustion air inlet to any other appli-

ance

K Clearance to a mechanical air supply inlet 6ft.(1.8M) 3ft.(.9M)

L Clearance under a veranda, porch, deck, or balcony

Clearance to each side o f the cente rline extended above or below vent terminal of the furnace to a dryer

or water heater vent, or other appliance’s direct vent intake or exhaust

Clearance to the vent termi nal of a dryer vent, wa ter heater vent, or other applia nces direct ve nt intake or

exhaust

O Clea rance from a plumbing vent sta ck 3ft.(.9M) 3ft.(.9M)

Clearance above paved sidewalk or paved driveway

locate d on publ ic property

(1) In accordance with the current C A N / CSA B (2) In accordance with the current ANSI Z22 3.1.NFPA 54, National Fuel Gas Code Notes:

1. The vent forthis appliance shall not terminate:

a. Over public walkways; or

b. Near soffit vents of crawl space vents or oth er areas where condensate or vap or could create a nuisance o r hazard or property damage; o r

c. Where condensate vapor could cause damage orcould be detrimental to the operation of regulators,relief valves,or otherequipment.

2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion products of adjacent vents. Recirculation can cause poor combustion, inlet conden sate problems, and accelerated co rrosion of the heat exch angers.

3. Avoid v enting und er a deck or large overhang. R ecirculation could o ccur and cause performance or system problems.

149.1, Natural Gas and Propane Installation Code.

12 in. (305 mm). 18 in. (457 mm) above roof surface. 12 in. (305 mm)

6 in. (152 mm) for appliances </--- 10,000 Btuh (3kW) 12 in. (305 mm) for appliances > 10,000 Btuh (3kW), and </--- 100,000 Btuh (30kW), 36 in. (914 mm) for appliances > 100,000 Btuh (30 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B149.1, clearances shall be in accordance with local installation codes and the requirements of the gas supplier and the manufacturer’s installation instructions.

3ft.(.9M)within15ft. (4.6 M) abovethemeter/ regulator assembly

6 in. (152 mm) for appliances </--- 10,000 Btuh (3kW) 12 in. (305 mm) for appliances > 10,000 Btuh (3kW), and </--- 100,000 Btuh (30kW), 36 in. (914 mm) for appliances > 100,000 Btuh (30 kW)

12 in. (305 mm). Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides b eneath the floo r.

12 in. (305 mm) 12 in. (305 mm)

3ft.(.9M) 3ft.(.9M)

7 ft. (2.1 M). A vent shall not terminate above a sidewalk or paved driveway that is locate d betwee n two single family dwellings and serves both dwellings.

4 ft. (1.2 M) belo w or to the side of the openi ng. 1 ft. (.3 M) above the opening.

For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B149.1, clearances shall be in accordance with loca l installation codes and the requi rements of the gas supplier and the manufacturer’s installation instructions.

3ft.(.9M)within15ft.(4.6M)abovethemeter/regulator assembly.

* 3 ft. (.9 M) * For clea rances not specified in ANSI Z223.1/NFPA54 orCAN/CSAB149.1,clearancesshall be in accordance with loca l install ation co des and the requirements of the gas supplier and the manufacturer’s installation instructions.

4 ft. (1.2 M) belo w or to the side of the openi ng. 1 ft. (.3 M) above the opening.

For clearances not specified in ANSI Z223.1/NFPA 54 or C A N / CSA B149.1, clearances shall be in accordance with loca l installation codes and the requi rements of the gas supplier and the manufacturer’s installation instructions.

7ft.(2.1M).

Fig. 45 -- Ventilated Combustion Air and Non--Direct Vent Termination Clearance

987MA

A11047

Page 54

987MA

V e r tical separation between comb ustion air and v ent

8 3/4 in. (222mm)f or 3 in. (76mm)ki t

6 3/4 in. (172mm)f or 2 in. (51mm) ki t

Maintain 12 in. (305mm)min. clearance abo ve highest anticipated sno w le ve l Maximum of 24 in.(614mm) abo v e roof

Note: "A" denotes 0 to < 2 in. Between the first 2 vents Third vent must be > 36 in. away

Roof T e rm ination (Pref erred)

18 in. maximu m

90 °

At least 36 in.

(914mm)

(457mm)

A t least 36 in

(914mm)

(51mm)

Concent ri c V ent and Comb ustion Ai r

Abandoned masonr y used as race wa y (per code)

(914mm)

in.

min fro m

ov erhang or roof

(typ)

in.

(305mm)

At least 36 in.

(914mm)

in. (305mm)

separation between

bottom ofcomb ustion air and bottom of v ent (typ)

Maintain 12 min. clearance abo ve highest anticipated sno w le ve l or grade whiche ve r is greater (typ)

Roof T er mination (pre fe rred)

Side wa ll te rm inatio n

in. (305mm)

of less than 12

At least

36 in.

(914mm)

above highest snow level

Maintain 12

in.

min. clearance abo ve highest anticipated sno w le ve l, maximum of 24 in . abo v e roof

in. (25mm)

t le

s t

Concent ri c V ent and Comb ustion - Air Side T e rm inatio n

(305mm)

maximum (typ) from wall to inlet

in. (305mm)

ov erhang or roof

Maintain 12 min. clearance ab ov e highest anticipated sno w le v el or grade which eve r is greate r

minimum fro m

(305mm)

in.

Fig. 46 -- Combustion Air and Vent Pipe Termination for Direct Vent (2--Pipe) System

Roof Termination (Preferred)

Ven t

(305mm)

Maintain 12 in .

minimum clearance

above highest anticipated

snow level maximum of

24 in. (610mm) above roof.

Abandoned masonry used as raceway (per code)

12 in. min. (305 mm)from

overhang or roof

Sidewall Termination

with Straight Pipe (preferred)

90°

Side wall termination with 2 elbows (preferred)

12 in. (305 mm) min. from

overhang or roof

Maintain 12 in. (305mm) minimum clearance above highest anticipated snow level or grade whichever is greater.

6 in. (152mm) minimum clearance

between wall and end of vent pipe.

10 in. (254mm) maximum pipe length

Maintain 12 in. (305mm) minimum clearance above highest anticipated snow level or grade whichever is greater

A05090

Fig. 47 -- Vent Pipe Termination for Non--Direct Vent and Ventilated Combustion Air System

A05091

Page 55

NOTE: This illustration is for reference only. Your unit may differ in appearance or may not include all components shown.

VENT

Angle

22.5 to

off wall

BRACKET

COUPLING

COMBUSTION-AIR (ELBOW PARALLEL

TO WALL)

OVERHANG OR ROOF

MAINTAIN 12 IN. CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL OR GRADE, WHICHEVER IS GREATER.

12 IN. SEPARATION BETWEEN BOTTOM OF COMBUSTION AIR AND BOTTOM OF VENT

L10F022

987MA

EXHAUST

OVERHANG

Clearance to overhang per code

12 in. (304.8mm) MIN. Ground Level OR Snow Level

Fig. 48 -- Alberta and Saskatchewan Vent Termination

A11346

Page 56

Ventilated Combustion Air intake pipe

Pipe hangar

3” (76 mm)

987MA

Ventilated Combustion Air intake termination in crawl space

12” (305 mm)

CRAWL SPACE

highest level of insulation

Fig. 49 -- Vent Terminations for Ventilated Combustion Air

ATTIC

A10497

Page 57

START--UP, ADJUSTMENT, AND SAFETY

CHECK

General

1. Furnace must have a 115-v power supply properly connected and grounded.

NOTE: Proper polarity must be maintained for 115-v wiring. Control status indicator light flashes rapidly and furnace does not operate if polarity is incorrect.

2. Thermostat wire connections at terminals R, W/W1, G, Y/Y2, etc. must be made at 24-v terminal block on furnace control. See communicating wall control instructions for proper wiring of communicating controls.

3. Natural gas service pressure must not exceed 0.5 psig (14in. w.c.), but must be no less than 0.16 psig (4.5-in. w.c.).

4. Blower door must be in place to complete 115-v electrical circuit to furnace.

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in intermittent unit operation or performance satisfaction.

These furnaces are equipped with a manual reset limit switch in burner assembly. This switch opens and shuts off power to the gas valve is an overheat condition (flame rollout) occurs in burner assembly. Correct inadequate combustion--air supply or improper venting condition before resetting switch. DO NOT jumper this switch.

Before operating furnace, check flame rollout manual reset switch for continuity. If necessary, press button to reset switch.

EAC-1 terminal is energized whenever blower operates. HUM terminal is only energized when blower is energized in heating.

Select Setup Switch Positions

There are 4 sets of setup switches on the furnace control board. These switches configure the furnace for correct application requirement. They also select the airflow settings for Air Conditioning and Continuous Fan CFMs.

The Setup Switch locations are shown and described on Fig. 54. The set up switches are also shown on the unit wiring label.

Setup Switches (SW1)

The furnace control has 8 setup switches that may be set to meet the application requirements. To set these setup switches for the appropriate requirement:

S Remove blower door. S Locate setup switches on furnace control. S Configure the set-up switches as necessary for the application. S Replace blower door.

NOTE: If a bypass humidifier is used, setup switch SW1-3 (Min/Int Rise Adjust) should be in ON position. This compensates for the increased temperature in return air resulting from bypass.

NOTE: If modulating dampers are used, blower motor automatically compensates for modulating dampers.

Air Conditioning (A/C) Setup Switches (SW2)

The air conditioning setup switches are used to match furnace airflow to cooling unit used.

To set the desired cooling airflow:

1. Remove blower door.

2. Locate A/C setup switches on furnace control.

3. Determine air conditioning tonnage used.

4. Configure the switches for the required cooling airflow.

NOTE: Excessive airflow caused by improper A/C switch setup may cause condensate blow-off in cooling mode.

5. Replace blower door.

Continuous Fan (CF) Setup Switches (SW3)

The CF setup switches are used to select desired airflow when thermostat is in continuous fan mode or to select low-cooling airflow for two-speed cooling units. This setup feature allows continuous fan airflow or low-cooling airflow to be adjusted. To set desired continuous fan airflow or low-cooling airflow:

1. Remove blower door.

2. Locate CF setup switches on furnace control.

3. Determine desired continuous fan airflow or low-cooling airflow.

4. Configure the switches for the required continuous fan or low--cooling airflow.

5. Replace blower door.

Additional Setup Switches (SW4)

The furnace control has 3 additional setup switches labeled SW4. Setup switch SW4-2 can be used to lock the furnace into intermediate heat. When setup switch SW4-2 is ON it will over ride setup switch SW1-2 if it is ON SW4--3 is used to adjust airflow. See communicating control instructions for use of SW4--1. To activate setup switch SW4-2 and SW4--3:

1. Remove blower door.

2. Locate setup switch SW4 on furnace control.

3. Configure the switches for the required heat stages and airflow if necessary.

4. Replace blower door.

Prime Condensate Trap with Water

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in intermittent unit operation or performance satisfaction.

Condensate trap must be PRIMED or proper draining may not occur. The condensate trap has two internal chambers which can ONLY be primed by pouring water into the inducer drain side of condensate trap.

1. Remove upper and middle collector box drain plugs opposite of the condensate trap. (See Fig. 57.)

2. Connect field-supplied 1/2-in. (13 mm) OD tube to upper collector box drain connection.

3. Insert field-supplied funnel into tube.

4. Pour one quart of water into funnel/tube. Water should run through collector box, overfill condensate trap, and flow into open field drain.

5. Remove funnel; replace collector box drain plug.

6. Connect field-supplied 1/2-in. (13 mm) OD tube to middle collector box drain port.

7. Pour one quart of water into funnel/tube. Water should run through collector box, overfill condensate trap, and flow into open field drain.

8. Remove funnel and tube from collector box and replace collector box drain plug.

987MA

Page 58

Purge Gas Lines

If not previously done, purge the lines after all connections have been made and check for leaks.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Adjustments

987MA

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in reduced furnace life.

DO NOT redrill orifices. Improper drilling (burrs, out--of--round holes, etc.) can cause excessive burner noise and misdirection of burner flames. This can result in flame impingement of heat exchangers, causing failures. (See Fig.

51.)

For proper operation and long term reliability, the Furnace input rate must be within +2 percent of input rate on furnace rating plate.

The gas input rate on rating plate is for installations at altitudes up to 2000 ft. (609.6M).

In the USA., the input rating for altitudes above 2000 ft. (609.6M) must be reduced by 2 percent for each 1000 ft. (304.8M) above sea level. Refer to Table 16.

In Canada, the input rating must be derated by 5 percent for altitudes of 2000 ft. (609.6M) to 4500 ft. (1371.6M) above sea level.

To adjust manifold pressure to obtain the proper input rate, first, determine if the furnace has the correct orifice installed. At higher altitudes or different gas heat contents, it may be necessary to change the factory orifice to a different orifice. Tables have been provided in the furnace installation instructions to match the required orifice to the manifold pressure to the heat content and specific gravity of the gas. To do this:

a. Obtain average heat value (at installed altitude) from local

b. Obtain average specific gravity from local gas supplier.

c. Find installation altitude range for your installation in the

d. Find closest natural gas heat value and specific gravity in

e. Follow heat value and specific gravity lines to point of

f. Check and verify burner orifice size in furnace. Never

NOTE: For Canadian altitudes of 2000 to 4500 ft. (609.6 to

1371.6M), use USA altitudes of 2001 to 3000 ft. (609.6 to

914.4M). NOTE: If orifice hole appears damaged or it is suspected to have

been redrilled, check orifice hole with a numbered drill bit of

CAUTION

gas supplier.

manifold pressure tables. See Table 19.

Table 19.

intersection to find orifice size and maximum and minimum manifold pressure settings for proper operation.

assume orifice size. Always check and verify.

correct size. Never redrill an orifice. A burr--free and squarely aligned orifice hole is essential for proper flame characteristics. See Example 1.

g. Replace original orifice with correct size, if required by

Table 19. Use only factory--supplied orifices. See EXAMPLE 1.

EXAMPLE 1

EXAMPLE: 0 -- 2000 ft. (0 -- 609.6M) altitude Heating value = 1050 Btu/cu ft. Specific gravity = 0.62 Therefore: Orifice No. 44 Manifold pressure: 3.4--in. w.c. for maximum heat, 0.55--in. w.c.

for minimum heat. * Furnace is shipped with No. 44 orifices. In this example, all main

burner orifices are the correct size and do not need to be changed to obtain proper input rate.

The inlet gas pressure must be checked with the furnace operating in maximum heat. This is necessary to make sure the inlet gas pressure does not fall below the minimum pressure of 4.5 in. w.c. for natural gas. The maximum inlet gas pressure is 13.6 in. of water column. If the inlet pressure is too low, you will not be able to adjust the manifold pressure to obtain the proper input rate. To check the inlet gas pressure:

1. Make sure the gas supply is turned off to the furnace and at the electric switch on the gas valve.

2. Remove the 1/8 in. NPT plug from the inlet pressure tap on the gas valve.

3. Connect a manometer to the inlet pressure tap on gas valve.

4. Turn on furnace power supply.

5. Turn gas supply manual shutoff valve to ON position.

6. Turn furnace gas valve switch to ON position.

7. Jumper the R to W/W1 and W2 thermostat connections at the furnace control board.

8. When main burners ignite, confirm inlet gas pressure is Between 4.5 in. w.c. and 13.6 in. w.c.

9. Remove jumper across thermostat connections to terminate call for heat. Wait until the blower off delay is completed.

10. Turn furnace gas valve electric switch to OFF position.

11. Turn gas supply manual shutoff valve to OFF position.

12. Turn off furnace power supply.

13. Remove manometer from the inlet pressure tap of the gas valve.

14. Apply pipe dope sparingly to end of inlet gas pipe plug and re--install in the gas valve.

For proper operation and long term reliability, the manifold pressure must be adjusted within +2 percent of input rate on furnace rating plate.

The modulating furnace manifold pressure is set at two points. The first point is Maximum Heat. The second point is Minimum Heat. Do not adjust Intermediate Heat manifold pressure. Intermediate Heat manifold pressure is checked as part of the temperature rise, but is not adjustable. Always adjust Maximum Heat first, then Minimum Heat.

NOTE: DO NOT set Maximum Heat manifold pressure less than

3.2--in. w.c. or more than 3.8 in. w.c. for natural gas. To adjust manifold pressure to obtain input rate for Maximum

Heat:

1. Make sure the gas supply is turned off to the furnace and at the electric switch on the gas valve.

2. Remove the 1/8 inch NPT plug from the outlet pressure tap on the gas valve.

3. Connect a manometer to the outlet pressure tap on gas valve.

Page 59

4. Turn on furnace power supply.

5. Turn gas supply manual shutoff valve to ON position.

6. Turn furnace gas valve switch to ON position.

7. Jumper the R to W/W1 and W2 thermostat connections at the furnace control board.

8. After the main burners ignite and the blower starts, confirm Maximum Heat manifold pressure is correct, based on the manifold pressure tables in the installation instructions.

9. To adjust the Maximum Heat manifold pressure, slowly turn adjusting screw counterclockwise to decrease manifold pressure or clockwise to increase manifold pressure. Turn adjustment no more than one click per second until you obtain the required manifold pressure.

10. Main burner flame should be clear blue, almost transparent.

11. After adjusting the Maximum Heat manifold pressure, remove jumpers across thermostat connections to terminate the call for heat.

12. Wait for blower off-delay to finish then reset 115-v power to furnace.

To adjust manifold pressure to obtain input rate for Minimum Heat:

1.TurnSW1--2ONandSW4--2mustbeOFF.

2. Jumper R and W/W1 thermostat connections on control to start furnace.

3. After the main burners ignite and the blower starts, confirm Minimum Heat manifold pressure is correct, based on the manifold pressure tables in the installation instructions.

4. To adjust the Minimum Heat manifold pressure, slowly turn adjusting screw counterclockwise to decrease manifold pressure or clockwise to increase manifold pressure. Turn adjustment no more than one click per second until you obtain the required manifold pressure.

5. After adjusting the manifold pressure, remove jumpers across thermostat connections to terminate the call for heat. Wait until the blower off delay is completed.

6. Move setup switch SW1-2 to the OFF position.

7. Turn gas supply manual shutoff valve to OFF position.

8. Turn off furnace power supply.

9. Remove manometer from the inlet pressure tap of the gas valve.

10. Apply pipe dope sparingly to end of inlet gas pipe plug and re-install in the gas valve.

11. Re-install cap over adjustment screw on the top of the gas valve.

CAUTION

FURNACE OVERHEATING HAZARD

Failure to follow this caution may result in shortened furnace life.

Set air temperature rise within limits specified on the rating plate to prevent reduced life of furnace components. Operation is within a few degrees of the mid--point of rise rangewhensetupswitchSW1--4isOFF.

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in overheating the heat exchangers or condensing flue gases in heat exchanger areas not designed for condensate.

Temperature rise must be within limits specified on unit rating plate. Operation is within a few degrees of midpoint ofriserangewhensetupswitchSW1--4isOFF.

Adjust Temperature Rise

When setup switch SW1-4 is ON, operation will be near the high end of the rise range for improved comfort.

Furnace must operate within ranges of temperature rise specified on the furnace rating plate. Determine air temperature rise as follows:

1. Place thermometers in return and supply ducts as near furnace as possible. Be sure thermometers do not see heat exchanger so that radiant heat does not affect readings. This practice is particularly important with straight-run ducts.

2. When thermometer readings stabilize, subtract return-air temperature from supply-air temperature to determine air temperature rise.

NOTE: Temperature rise can be determined for Minimum Heat, Intermediate Heat and Maximum Heat operation by locking the furnace in each mode of operation. The mode of operation is based on the position of Set-up switch SW1-2 and SW4-2 on the furnace control board.

The furnace is capable of automatically providing proper airflow to maintain the temperature rise within the range specified on furnace rating plate. If temperature rise is outside this range, proceed as follows:

a. Check gas input for minimum, intermediate and maximum

heat operation.

b. Check derate for altitude if applicable.

c. Check all return and supply ducts for excessive restrictions

causing static pressure greater than 0.5-in. w.c.

d. Ensure Min/Int Rise Adjust switch SW1--3 on furnace

control is in ON position when a bypass humidifier is used. (See Fig. 54 for switch location.)

e. Check Troubleshooting Guide for Variable--Speed Step

Modulating Condensing Furnaces.

To lock the furnace in Minimum Heat:

1. Turn SW1--2 ON at the furnace control. Set up switch SW4--2 must be OFF.

2. Connect a jumper across R and W/W1 at the thermostat terminals at the furnace control.

3. Allow the burners to ignite and the blower to turn on.

4. Allow the supply temperature to stabilize and verify the proper rise range.

If the temperature rise is too high or too low in Minimum Heat:

1. Remove jumpers from R and W/W1.

2. Wait until the blower off delay is completed.

3. Turn 115 VAC power off.

4. Check the position of Set up switch SW1--3. When set to ON, airflow is raised 18% for Minimum Heat and for Intermediate Heat. Factory default position is OFF.

5. Turn 115 VAC power on.

6. Re--check Minimum Heat Temperature Rise

987MA

Page 60

To lock the furnace in Intermediate Heat:

1. Turn SW1--2 OFF and SW4--2 ON at the furnace control.

2. Connect a jumper across R and W/W1 at the thermostat terminals at the furnace control.

3. Allow the burners to ignite and the blower to turn on.

4. Allow the supply temperature to stabilize and verify the proper rise range.

If the temperature rise is too high or too low in Intermediate Heat:

1. Remove jumpers from R and W/W1.

2. Wait until the blower off delay is completed.

3. Turn 115 VAC power off.

4. Check the position of Set up switch SW1--3. When set to ON, airflow is raised 18% for Minimum Heat and for Intermediate Heat. Factory default position is OFF.

5. Turn 115 VAC power on.

6. Re--check Minimum Heat Temperature Rise .

To lock the furnace in Maximum Heat:

987MA

1. Connect a jumper across R and W/W1 and W2 at the thermostat terminals at the furnace control.

2. Allow the burners to ignite and the blower to turn on.

3. Allow the supply temperature to stabilize and verify the proper rise range.

If the temperature rise is too high or too low in Maximum Heat:

1. Remove jumpers from R and W/W1.

2. Wait until the blower off delay is completed.

3. Turn 115 VAC power off.

4. Check the position of Set up switch SW1--4. When set to OFF, airflow is raised 9% for Minimum Heat, 7% for Intermediate Heat and 15% for Maximum Heat. Factory default position is ON.

5. Turn 115 VAC power on.

6. Re--check Minimum Heat Temperature Rise.

After the temperature rise has been verified:

1. Remove jumpers from thermostat terminals.

2. Allow the blower off delay to complete.

3. Turn Set up switches SW1--2 and SW4--2 to the OFF position.

4. Install blower door.

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Reinstall manifold pressure tap plug in gas valve to prevent gas leak.

CAUTION

FURNACE OVERHEATING HAZARD

Failure to follow this caution may result in reduced furnace life.

Recheck temperature rise. It must be within limits specified on the rating plate. Recommended operation is at the mid--point of rise range or slightly above.

f. Proceed to “Set Blower Off Delay” before installing

blower door.

Adjust Blower Off Delay (Heat Mode)

a. Remove blower door if installed.

b.TurnDipswitchSW--7orSW--8ONorOFFfordesired

blower off delay. (See Table 17 and Fig. 34 , 54 and 63.)

Adjust Cooling Airflow -- Single Stage and High Stage

Cooling

The ECM blower can be adjusted for a range of airflow for Low Speed or High Speed cooling. See Table 7--Air Delivery -- CFM (With Filter ). Depending on the model size, the cooling airflow can be adjusted from 1.5 to 6 tons based on 350 CFM ton.

The cooling airflow is adjusted by turning Setup switches SW2--1, SW2--2 and SW2--3 either ON or OFF. Select the required airflow from Table 7. Table 7 is based on 350 CFM per ton. For other CFM per ton setup switch selections. See Fig. 34 and Fig. 54 and Fig.63.

NOTE: 6 ton airflow will truncate at 2200 CFM on applicable models. For a complete explanation of cooling airflow, refer to the section titled “Sequence of Operation.”

Adjust Continuous Fan Airflow/Low Speed Cooling

The ECM blower motor can be adjusted for continuous fan speeds different than heating or cooling fan speed. See Table 7 -- Air Delivery -- CFM (With Filter). Select the required continuous fan airflow from Fig. 54 and Table 7. Other airflow options are available via SW4--3. See Table 7.

The continuous fan speed is also the fan speed for low speed cooling when furnace is used with a 2--speed cooling unit. Adjust the Continuous Fan CFM to match the airflow required for low speed cooling. Select the required airflow from Fig. 54. For other CFM per ton setup switch selections. (See Fig. 34 and Fig. 54.) The airflow selected for low speed cooling will also be the airflow used for continuous fan. The continuous fan speed can be further adjusted at the thermostat using the “Comfort Fan” select function. Changing the continuous fan speed at the thermostat DOES NOT change the low speed cooling airflow selected at the control board.

Airflow

Adjust Thermostat Heat Anticipator.

a. Mechanical thermostat. Set thermostat heat anticipator to

match the amp. draw of the electrical components in the R--W/W1 circuit. Accurate amp. draw readings can be obtained at the wires normally connected to thermostat subbaseterminals,R and W.The thermostatanticipator should NOT be in the circuit while measuring current.

(1.) Set SW1--2 switch on furnace control board to ON. (2.) Remove thermostat from subbase or from wall. (3.) Connect an amp. meter as shown in Fig. 52 across

the R and W subbase terminals or R and W wires at wall.

(4.) Record amp. draw across terminals when furnace is

in minimum heat and after blower starts.

(5.) Set heat anticipator on thermostat per thermostat

instructions and install on subbase or wall. (6.) Turn SW1--2 switch OFF. (7.) Install blower door.

b. Electronic thermostat: Set cycle rate for 3 cycles per hr.

Check Safety Controls

The flame sensor, gas valve, and pressure switch were all checked in the Start--up procedure section as part of normal operation.

1. Check Main Limit Switch This control shuts off combustion system and energizes air-circulating blower motor, if furnace overheats. By using this method to check limit control, it can be established that limit is functioning properly and will operate if there is a re-

Page 61

stricted return--air supply or motor failure. If limit control does not function during this test, cause must be determined and corrected.

a. Run furnace for at least 5 minutes.

b. Gradually block offreturn air with a pieceof cardboard or

sheet metal until the limit trips.

c. Unblock return air to permit normal circulation.

d. Burners will re--light when furnace cools down.

2. Check Pressure Switch(es) This control proves operation of the draft inducer blower.

a. Turn off 115--v power to furnace.

b. Disconnect inducer motor lead wires from wire harness.

c. Turn on 115--v power to furnace.

d. Set thermostat to “call for heat” and wait 1 minute. When

pressure switch is functioning properly, hot surfaceigniter should NOT glow and control diagnostic light flashes a status code 32. If hot surface igniter glows when inducer motor is disconnected, shut down furnace immediately.

e. Determine reason pressure switch did not function prop-

erly and correct condition.

f. Turn off 115--v power to furnace.

g. Reconnect inducer motor wires, replace blower door, and

turn on 115--v power.

h. Blower will run for 90 seconds before beginning the call

for heat again.

i. Furnace should ignite normally.

Checklist

1. Put away tools and instruments. Clean up debris.

2. Verify that switches SW1--1 and SW1--6 are OFF and other setup switches are set as desired. Verify that switches SW1--7 and SW1--8 for the blower OFF DELAY are set as desired per Table 17.

3. Verify that blower and control doors are properly installed.

4. Cycle test furnace with room thermostat.

5. Check operation of accessories per manufacturer’s instructions.

6. Review Owner’s Manual with owner.

7. Attach literature packet to furnace.

ON/OFF Switch

MODULATING

Fig. 50 -- Gas Valve

BURNER

Fig. 51 -- Orifice Hole

THERMOSTAT SUBBASE TERMINALS WITH THERMOSTAT REMOVED (ANITICIPATOR, CLOCK, ETC., MUST BE OUT OF CIRCUIT.)

HOOK-AROUND AMMETER

R Y W G

A10496

ORIFICE

987MA

A93059

Turn screw 1 click per second to adjust rate. Clockwise to increase rate, counter clockwise to decrease rate.

Inlet Pressure Tap

GAS FLOW

Manifold Pressure Tap

Min/Max Heat Adust (Under Cap)

1/2” NPT Outlet

10 TURNS

FROM UNIT 24-V CONTROL TERMINALS

EXAMPLE:

5.0 AMPS ON AMMETER 10 TURNS AROUND JAWS

0.5 AMPS FOR THERMOSTAT

ANTICIPATOR SETTING

Fig. 52 -- Amp. Draw Check with Ammeter

A96316

Page 62

987MA

A11542

Fig. 53 -- Service Label Information

Page 63

Furnace Setup Switch Description

Off Del

Allows additional CFM per ton selections when used with SW

SW1-1 Status Code Recovery OFF

Minimum Heat Only

SW1-2

SW1-3

SW1-4

SW1-5 CFM per ton adjust OFF

SW1-6 Component Self Test OFF

SW1-7 & SW1-8 Blower OFF delay ON or OFF

SW4-2

(Adaptive Heat Mode

when SW1-2 and SW4-2

are OFF)

Min/Int Heat Rise

Adjustment

Comfort/Efficiency

Adjustment

Intermendiate Heat

Only

(Adaptive Heat Mode

when both SW1-2 and

SW4-2 are OFF)

OFF

ESU FO NOITPIRCSEDNOITISOP LAMRONEMAN HCTIWSHCTIWS PUTES

Turn ON to retrieve up to 7 stored status codes for troubleshooting assistance when R thermostat lead is disconnected. When SW1-2 and SW4-2 are OFF allows Modulating operation with a single stage thermostat. Turn ON SW1-2 when using two-stage thermostat to allow Minimum Heat operation when R to W/W1 closed and a Maximum heat operation when R to W/W1 and R to W2 close.

urn ON to increase Minimum Heat and Intermediate Heat airflow by 18 percent. This compensates for increased return air temperature caused with bypass humidifier. This also increases the Intermediate Heat inducer speed 15 percent. Turn ON to decrease Minimum heat airflow by 9 percent, Intermediate Heat airflow 7 percent and Maximum Heat airflow 15 percent for maximum comfort. Turn ON for 400 CFM per ton, Turn OFF for 350 CFM per ton. See also SW4.

Turn ON to initiate Component Self Test for troubleshooting assistance when R thermostat lead is disconnected. Turn OFF when Self Test is completed.

ower seconds. See table in Adjustments section or refer to unit wiring diagram.

When SW1-2 and SW4-2 are OFF allows Modulating operation with a single stage thermostat. Turn ON SW4-2 when using two-stage thermostat to allow Intermediate Heat operation when R to W/W1 closed and a Maximum heat operation when R to W/W1 and R to W2 close.

ay time – adjustable 90 seconds to 180

987MA

SW2

SW3

1-5

325 CFM per ton (nominal) when SW 4-3 ON and SW 1-5 OFF

350 CFM per ton (nominal) when SW 4-3 OFF and SW 1-5 OFF

SW4-3

1 2 3

SW 2, AC (Cooling Airflow) SETUP SWITCHES

The AC setup switch selects desired cooling or high stage cooling (two stage units) airflow.

See Air Delivery Tables for specific switch settings

SW 3, CF (Continuous Fan) SETUP SWITCHES

The CF setup switch selects desired Continuous Fan Airflow

The CF switch position is the low cooling airflow selection for two stage cooling units.

The CFM values in the Air Delivery Tables for SW 3 settings are the same as SW 2 settings.

SW 3 cannot be set for airflow higher than SW 2

See Air Delivery Tables for specific switch settings

CFM per ton Adjust

AIR CONDITIONING (A/C) SETUP SWITCHES

CONTINUOUS FAN (CF) SETUP SWITCHES

OFF

370 CFM per ton (nominal) when SW4-3 ON and SW 1-5 ON

400 CFM per ton (nominal) when SW 1-5 ON and SW 4-3 OFF

See Air Delivery Tables for model specific CFM vs. static

ressure

A11541 AMV98

Fig. 54 -- Furnace Setup Switch Description

Page 64

Table 16 – Altitude Derate Multiplier for U.S.A.*

ALTITUDE

FT. M

0–2000 0 --- 6 1 0 0 1.00 2001–3000 610---914 4 --- 6 0.95 3001–4000 914---1219 6 --- 8 0.93 4001–5000 1219 ---1524 8 --- 1 0 0.91 5001–6000 1524 ---1829 10 ---12 0.89 6001–7000 1829 ---2134 12 ---14 0.87 7001–8000 2134--- 2438 14 ---16 0.85 8001–9000 2438--- 2743 16 ---18 0.83

9001–10,000 2743--- 3048 18 ---20 0.81

*Derate multiplier factors are based on midpoint altitude for al titude ran ge.

SECONDS

FOR 1 REVOLUTION

987MA

10 360 720 1800 50 72 144 360 11 327 655 1636 51 71 141 355 12 300 600 1500 52 69 138 346 13 277 555 1385 53 68 136 340 14 257 514 1286 54 67 133 333 15 240 480 1200 55 65 131 327 16 225 450 1125 56 64 129 321 17 212 424 1059 57 63 126 316 18 200 400 1000 58 62 124 310 19 189 379 947 59 61 122 305 20 180 360 900 60 60 120 300 21 171 343 857 62 58 116 290 22 164 327 818 64 56 112 281 23 157 313 783 66 54 109 273 24 150 300 750 68 53 106 265 25 144 288 720 70 51 103 257 26 138 277 692 72 50 100 250 27 133 267 667 74 48 97 243 28 129 257 643 76 47 95 237 29 124 248 621 78 46 92 231 30 120 240 600 80 45 90 225 31 116 232 581 82 44 88 220 32 113 225 563 84 43 86 214 33 109 218 545 86 42 84 209 34 106 212 529 88 41 82 205 35 103 206 514 90 40 80 200 36 100 200 500 92 39 78 196 37 97 195 486 94 38 76 192 38 95 189 474 96 38 75 188 39 92 185 462 98 37 74 184 40 90 180 450 100 36 72 180 41 88 176 439 102 35 71 178 42 86 172 429 104 35 69 173 43 84 167 419 106 34 68 170 44 82 164 409 108 33 67 167 45 80 160 400 110 33 65 164 46 78 157 391 112 32 64 161 47 76 153 383 116 31 62 155 48 75 150 375 120 30 60 150 49 73 147 367

PERCENT

DERATE

SIZE OF TEST DIAL

1CuFt. 2CuFt. 5CuFt. 1CuFt. 2CuFt. 5CuFt.

DERATE

MULTIPLIER

FACTOR*

DESIRED HEATING MODE

BLOWER OFF DELAY (SEC.)

Table 18 – Gas Rate (CU ft./hr)

FOR 1 REVOLUTION

Table 17 – Blower Off Delay Setup Switch

SETUP SWITCH

( S W 1 --- 7 A N D --- 8 )

POSITION

S W 1 --- 7 S W 1 --- 8

90 OFF OFF 120 ON OFF 150 OFF ON 180 ON ON

SECONDS

SIZE OF TEST DIAL

Page 65

Table 19 – OrificeSize and Manifold Pressure (In. W.C.) for Gas Input Rate

MODULATING FURNACE

(TABULATED DAT A BASED ON 20,000 BTUH MAX-HEAT / 8,000 BT UH MIN-HEAT PER BURNER,

DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)

ALTITUDE

RANGE

ft (m)

092543 3.6 /0.55 43 3.7 /0.60 43 3.8 /0.60 42 3.2 /0.50

(0) 950 43 3.4 /0.55 43 3.5 /0.55 43 3.6 /0.60 43 3.7 /0.60

to 1000 44 3.5 /0.55 44 3.6 /0.60 44 3.8 /0.60 43 3.4 /0.55

U.S.A. and CanadaU.S.A. and CanadaU.S.A. Only

U.S.A. On

2000 1050 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55 44 3.5 /0.55

(610) 1075 45 3.7 /0.60 45 3.8 /0.60 44 3.3 /0.50 44 3.4 /0.55

U.S.A. 800 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.55 42 3.7 /0.60

2001 (611) 825 43 3.8 /0.60 42 3.3 /0.50 42 3.4 /0.55 42 3.5 /0.55

to 850 43 3.6 /0.60 43 3.7 /0.60 42 3.2 /0.50 42 3.3 /0.55

3000 (914) 875 43 3.4 /0.55 43 3.5 /0.55 43 3.7 /0.60 43 3.8 /0.60

Canada 925 44 3.5 /0.55 44 3.6 /0.60 44 3.8 /0.60 43 3.4 /0.55

2001 (611) 950 44 3.3 /0.55 44 3.4 /0.55 44 3.6 /0.55 44 3.7 /0.60

to 975 44 3.2 /0.50 44 3.3 /0.50 44 3.4 /0.55 44 3.5 /0.55

4500 (1372) 1000 46 3.8 /0.60 45 3.8 /0.60 44 3.2 /0.50 44 3.3 /0.55

3001 800 43 3.8 /0.60 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55

(915) 825 43 3.6 /0.55 43 3.7 /0.60 43 3.8 /0.60 42 3.2 /0.50

4000 900 44 3.4 /0.55 44 3.5 /0.55 44 3.7 /0.60 44 3.8 /0.60

(1219) 925 44 3.2 /0.50 44 3.4 /0.55 44 3.5 /0.55 44 3.6 /0.55

4001 775 43 3.7 /0.60 43 3.8 /0.60 42 3.3 /0.50 42 3.4 /0.55

(1220) 800 43 3.5 /0.55 43 3.6 /0.60 43 3.7 /0.60 43 3.8 /0.60

5000 875 44 3.3 /0.55 44 3.5 /0.55 44 3.6 /0.55 44 3.7 /0.60

(1524) 900 44 3.2 /0.50 44 3.3 /0.50 44 3.4 /0.55 44 3.5 /0.55

5001 750 43 3.7 /0.60 43 3.8 /0.60 42 3.2 /0.50 42 3.3 /0.55

(1525) 775 43 3.4 /0.55 43 3.5 /0.55 43 3.7 /0.60 43 3.8 /0.60

6000 850 44 3.3 /0.50 44 3.4 /0.55 44 3.5 /0.55 44 3.6 /0.60

(1829) 875 45 3.7 /0.60 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55

6001 700 42 3.2 /0.50 42 3.3 /0.50 42 3.4 /0.55 42 3.5 /0.55

(1830) 725 43 3.6 /0.60 43 3.7 /0.60 43 3.8 /0.60 42 3.3 /0.50

7000 800 44 3.4 /0.55 44 3.5 /0.55 44 3.6 /0.60 44 3.7 /0.60

(2133) 825 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55 44 3.5 /0.55

HEATVALUE0.580.600.620.64

AT ALTITUDE Orifice Mnfld Press Orifice Mnfld Press Orifice Mnf ld Press Orifice Mnfld Press

(Btu/cu ft) No. Max/Min No. Max/Min N o. Max/Min No. Max/Min

900 43 3.8 /0.60 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55

975 44 3.7 /0.60 44 3.8 /0.60 43 3.4 /0.55 43 3.6 /0.55

1025 44 3.3 /0.55 44 3.5 /0.55 44 3.6 /0.55 44 3.7 /0.60

1100 46 3.7 /0.60 46 3.8 /0.60 45 3.8 /0.60 44 3.2 /0.50

900 44 3.7 /0.60 44 3.8 /0.60 43 3.5 /0.55 43 3.6 /0.55

775 42 3.3 /0.55 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.60

850 44 3.8 /0.60 43 3.5 /0.55 43 3.6 /0.55 43 3.7 /0.60

875 44 3.6 /0.60 44 3.7 /0.60

950 45 3.7 /0.60 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55

750 42 3.3 /0.50 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.55

825 44 3.8 /0.60 43 3.4 /0.55 43 3.5 /0.55 43 3.6 /0.60

850 44 3.5 /0.55 44 3.7 /0.60 44 3.8 /0.60 43 3.4 /0.55

925 46 3.8 /0.60 45 3.7 /0.60 44 3.2 /0.50 44 3.3 /0.55

725 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55 42 3.5 /0.55

800 44 3.7 /0.60 44 3.8 /0.60 43 3.4 /0.55 43 3.5 /0.55

825 44 3.5 /0.55 44 3.6 /0.55 44 3.7 /0.60 44 3.8 /0.60

900 46 3.7 /0.60 46 3.8 /0.60 45 3.8 /0.60 44 3.2 /0.50

675 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.60 42 3.8 /0.60

750 43 3.4 /0.55 43 3.5 /0.55 43 3.6 /0.55 43 3.7 /0.60

775 44 3.6 /0.60 44 3.7 /0.60 43 3.4 /0.55 43 3.5 /0.55

850 46 3.8 /0.60 45 3.8 /0.60 44 3.2 /0.50 44 3.3 /0.55

43 3.4 /0.55 43 3.5 /0.55

SAGLARUTANFOYTIVARGCIFICEPSSAG.GVA

987MA

A11251A

Page 66

987MA

Table 19 -- Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Continued)

(TABULATED DAT A BASED ON 20,000 BTUH MAX-HEAT / 8,000 BT UH MIN-HEAT PER BURNER,

DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)

ALTITUDE

RANGE

ft (m)

7001 675 43 3.8 /0.60 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55

(2134) 700 43 3.5 /0.55 43 3.7 /0.60 43 3.8 /0.60 42 3.2 /0.50

U.S.A. Only

* Orifice numbers shown in BOLD are factory-installed.

8000 775 44 3.3 /0.55 44 3.4 /0.55 44 3.5 /0.55 44 3.7 /0.60

(2438) 800 45 3.8 /0.60 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55

8001 650 43 3.8 /0.60 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55

(2439) 675 43 3.5 /0.55 43 3.6 /0.60 43 3.7 /0.60 42 3.2 /0.50

9000 750 44 3.3 /0.50 44 3.4 /0.55 44 3.5 /0.55 44 3.6 /0.55

(2743) 775 45 3.7 /0.60 44 3.2 /0.50 44 3.3 /0.50 44 3.4 /0.55

9001 600 42 3.3 /0.55 42 3.4 /0.55 42 3.6 /0.55 42 3.7 /0.60

(2744) 625 43 3.7 /0.60 42 3.2 /0.50 42 3.3 /0.55 42 3.4 /0.55

10000 700 44 3.4 /0.55 44 3.5 /0.55 44 3.7 /0.60 44 3.8 /0.60

(3048) 725 44 3.2 /0.50 44 3.3 /0.55 44 3.4 /0.55 44 3.5 /0.55

HEATVALUE0.580.600.620.64

AT ALTITUDE Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press

(Btu/cu ft) No. Max/Min No. Max/Min No. Max/Min No. Max/Min

650 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.60 42 3.7 /0.60

725 44 3.8 /0.60 43 3.4 /0.55 43 3.5 /0.55 43 3.6 /0.60

750 44 3.5 /0.55 44 3.7 /0.60 44 3.8 /0.60 43 3.4 /0.55

825 46 3.7 /0.60 46 3.8 /0.60 45 3.8 /0.60 44 3.2 /0.50

625 42 3.4 /0.55 42 3.5 /0.55 42 3.6 /0.55 42 3.7 /0.60

700 44 3.7 /0.60 43 3.4 /0.55 43 3.5 /0.55 43 3.6 /0.55

725 44 3.5 /0.55 44 3.6 /0.60 44 3.7 /0.60 44 3.8 /0.60

650 43 3.5 /0.55 43 3.6 /0.55 43 3.7 /0.60 43 3.8 /0.60

675 44 3.7 /0.60 44 3.8 /0.60 43 3.4 /0.55 43 3.5 /0.55

MODULATING FURNACE

SAGLARUTANFOYTIVARGCIFICEPSSAG.GVA

A11251B

Page 67

SERVICE AND MAINTENANCE

PROCEDURES

WARNING

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

The ability to properly perform maintenance on this equipment requires certain knowledge, mechanical skills, tools, and equipment. If you do not possess these, do not attempt to perform any service and maintenance on this equipment other than those procedures recommended in the Owner’s Manual.

CAUTION

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental pollution.

Remove and recycle all components or materials (i.e. oil, refrigerant, control board, etc.) before unit final disposal.

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death, or property damage.

Before installing, modifying, or servicing system, main electrical disconnect switch must be in the OFF position and install a lockout tag. There may be more than one disconnect switch. Lock out and tag switch with a suitable warning label. Verify proper operation after servicing.

CAUTION

ELECTRICAL OPERATION HAZARD

Failure to follow this caution may result in improper furnace operation or failure of furnace.

Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation.

General

These instructions are written as if the furnace is installed in an upflow application. An upflow furnace application is where the blower is located below the combustion and controls section of the furnace, and conditioned air is discharged upward. Since this furnace can be installed in any of the 4 positions shown in Fig. 2, you must revise your orientation to component location accordingly.

Electrical Controls and Wiring

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

There may be more than one electrical supply to the furnace. Check accessories and cooling unit for additional electrical supplies that must be shut off during furnace servicing. Lock out and tag switch with a suitable warning label.

The electrical ground and polarity for 115--v wiring must be properly maintained. Refer to Fig. 33 for field wiring information and to Fig. 63 for furnace wiring information.

NOTE: If the polarity is not correct, the STATUS LED on the control will flash rapidly and prevent the furnace from heating. The control system also requires an earth ground for proper operation of the control and flame--sensing electrode.

The 24--v circuit contains an automotive--type, 3--amp. fuse located on the control. (See Fig. 34.) Any shorts of the 24--v wiring during installation, service, or maintenance will cause this fuse to blow. If fuse replacement is required, use ONLY a 3--amp. fuse. The control LED will display status code 24 when fuse needs to be replaced.

Troubleshooting

Refer to the service label. (See Fig. 53—Service Label.) The Troubleshooting Guide (See Fig. 62) can be a useful tool in

isolating furnace operation problems. Beginning with the word “Start,” answer each question and follow the appropriate arrow to the next item.

The Guide will help to identify the problem or failed component. After replacing any component, verify correct operation sequence.

Proper instrumentation is required to service electrical controls. The control in this furnace is equipped with a Status Code LED (Light--Emitting Diode) to aid in installation, servicing, and troubleshooting. Status codes can be viewed at the indicator in blower door. The amber furnace control LED is either ON continuously, rapid flashing, or a code composed of 2 digits. The first digit is the number of short flashes, the second digit is the number of long flashes.

For an explanation of status codes, refer to service label located on control door or Fig. 53, and the troubleshooting guide which can be obtained from your distributor.

Retrieving Stored Fault Codes

The stored status codes will NOT be erased from the control memory, when 115-- or 24--v power is interrupted. The control will store up to the last 7 Status Codes in order of occurrence.

1. To retrieve status codes, proceed with the following:

NOTE: NO thermostat signal may be present at control, and all blower--OFF delays must be completed.

a. Leave 115--v power to furnace turned on.

b. Look into blower door indicator for current LED status.

c. Remove blower door.

NOTE: The Status Codes cannot be retrieved by disconnecting the limit switch. To retrieve Status Codes, follow the procedure below.

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2. Turn Setup Switch, SW1--1 “ON.”

3. Manually close blower door switch.

4. Control will flash up to 7 Status Codes.

5. The last Status Code, or 8th Code, will be Code 11.

6. Turn SW1--1 “OFF.”

7. A continuously--lit Amber LED will appear and indicates proper operation.

8. Release blower door switch, install blower door and refer to the SERVICE label on the control door for more information.

Component Self--Test

Component Test can ONLY be initiated by performing the following:

1. Remove blower door.

2. Remove the wire from the “R” terminal of the control board.

3. Turn Setup Switch, SW--1--6 “ON.”

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4. Manually close blower door switch.

Blower door switch opens 115--v power to control. No component operation can occur unless switch is closed. Caution must be taken when manually closing this switch for service purposes.

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, or death.

Blower door switch opens 115--v power to furnace control. No component operation can occur unless switch is closed. Exercise caution to avoid electrical shock from exposed electrical components when manually closing this switch for service purposes.

Care and Maintenance

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

Never store flammable or combustible materials on, near, or in contact with the furnace, such as:

1. Spray or aerosol cans, rags, brooms, dust mops, vacuum cleaners, or other cleaning tools.

2. Soap powders, bleaches, waxes or other cleaning compounds, plastic or plastic containers, gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids, or other volatile fluids.

3. Paint thinners and other painting compounds, paper bags, or other paper products. Exposure to these materials could lead to corrosion of the heat exchangers.

For continuing high performance and to minimize possible furnace failure, periodic maintenance must be performed on this furnace. Consult your local dealer about proper frequency of maintenance and the availability of a maintenance contract.

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or service. Follow the operating instructions on the label attached to the furnace.

5. Component Test sequence will function as follows: a. The furnace control CPU turns the inducer motor IDM ON

at medium speed and keeps it ON through Step 4.

b. The furnace control CPU will test communication with the

modulating gas valve GV.

c. After waiting 15 seconds the furnace control CPU turns the

hot surface igniter ON for 15 seconds, then OFF.

d. The furnace control CPU then turns the blower motor

BLWM ON at mid-range airflow for 15 seconds, then OFF.

e. After shutting the blower motor BLWM OFF the furnace

control CPU shuts the inducer motor IDM OFF.

NOTE: The EAC terminals are energized when the blower is operating.

After the component test is completed, 1 or more status codes (11, 25, 35, 41, or 42) will flash. See Service Label on control door or Service/Status Code Instructions for explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1-6 to OFF and then back ON.

f.TurnsetupswitchSW1--6OFF.

6. RELEASE BLOWER DOOR SWITCH, reattach wire to

“R” terminal on furnace control board and replace blower door.

WARNING

CARBON MONOXIDE POISONING AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

Never operate furnace without a filter or filtration device installed. Never operate a furnace with filter or filtration device access doors removed.

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care

and wear appropriate protective clothing, safety glasses and gloves when handling parts, and servicing furnaces.

The minimum maintenance on this furnace is as follows:

1. Check and clean air filter each month or more frequently if required. Replace if torn.

2. Check blower motor and wheel for cleanliness each heating and cooling season. Clean as necessary.

3. Check electrical connections for tightness and controls for proper operation each heating season. Service as necessary.

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4. Inspect burner compartment before each heating season for rust, corrosion, soot or excessive dust. If necessary, have furnace and burner serviced by a qualified service agency.

5. Inspect the vent pipe/vent system before each heating season for water leakage, sagging pipes or broken fittings. Have vent pipes/vent system serviced by a qualified service agency.

6. Inspect any accessories attached to the furnace such as a humidifier or electronic air cleaner. Perform any service or maintenance to the accessories as recommended in the accessory instructions.

Cleaning and/or Replacing Air Filter

The air filter type may vary depending on the application or orientation. The filter is external to the furnace casing. There are no provisions for an internal filter with this furnace. See “Filter Arrangement” under the “Installation” section of this manual.

WARNING

CARBON MONOXIDE POISONING AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death and/or property damage.

Never operate furnace without a filter or filtration device installed. Never operate a furnace with filter or filtration device access doors removed.

NOTE: If the filter has an airflow direction arrow, the arrow must point toward the blower. To clean or replace filters, proceed as follows:

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death, or property damage.

1. Turn off electrical supply to furnace.

2. Remove filter cabinet door.

3. Slide filter out of cabinet.

4. If equipped with permanent, washable filter, clean filter by spraying cold tap water through filter in opposite direction of airflow. Rinse filter and let dry. Oiling or coating of the filter is not recommended.

5. If equipped with factory specified disposable media filter, replace only with a factory specified media filter of the same size.

6. Slide filter into cabinet.

7. Replace filter cabinet door.

8. Turn on electrical supply to furnace.

Blower Motor and Wheel Maintenance

To ensure long life, economy, and high efficiency, clean accumulated dirt and grease from blower wheel and motor annually.

The inducer and blower motors are pre--lubricated and require no additional lubrication. These motors can be identified by the absence of oil ports on each end of the motor.

The following items should be performed by a qualified service technician. Clean blower motor and wheel as follows:

1. Turn off electrical supply to furnace.

2. Remove blower door.

3. All factory wires can be left connected, but field thermostat and accessory wiring may need to be disconnected depending on their length and routing.

4. If the vent and combustion air pipe passes through the blower compartment, it will be necessary to remove the pipes from the blower compartment.

Disconnect the vent and combustion air pipe by:

a. Loosen theclamps on the vent couplingsand combustion

air pipe external to the furnace.

b. Separate the pipes from the couplings and move them

aside.

c. Loosen the clamps on the vent couplings andcombustion

air pipe located on the blower shelf.

d. Separate the pipes from the blower compartment and set

aside.

e. Removethecouplingsfromthepipeadaptersand set aside.

f. After servicing the blower, reverse steps a through e.

g. Tighten all clamps 15 lb --in.

See Fig. 60 For Steps 5 through 14.

5. Remove screws securing blower assembly to blower shelf and slide blower assembly out of furnace. Detach ground wire and disconnect blower motor harness plugs from blower motor.

NOTE: Blower wheel is fragile. Use care.

6. Clean blower wheel and motor by using a vacuum with soft brush attachment. Be careful not to disturb balance weights (clips) on blower wheel vanes. Do not bend wheel or blades as balance will be affected.

7. If greasy residue is present on blower wheel, remove wheel from the blower housing and wash it with an appropriate degreaser. To remove wheel:

a. Mark blower wheel location on shaft before disassembly

to ensure proper reassembly.

b. Loosen setscrew holding blower wheel on motor shaft.

NOTE: Mark blower mounting arms and blower housing so each arm is positioned at the same hole location during reassembly.

c. Mark blower wheel orientation and cutoff plate location to

ensure proper reassembly.

d. Remove screws securing cutoff plate and remove cutoff

plate from housing.

e. Remove bolts holding motor mounts to blower housing

and slide motor and mounts out of housing.

f. Remove blower wheel from housing.

g. Clean wheel per instructions on degreaser cleaner. Do not

get degreaser in motor.

8. Reassemble motor and blower wheel by reversing items 7b through 7f. Ensure wheel is positioned for proper rotation.

9. Torque motor mounting bolts to 40 +/-- 10 lb--in. when reassembling.

10. Torque blower wheel set screw to 160 +/-- 20 lb--in. when reassembling.

11. Verify that blower wheel is centered in blower housing and set screw contacts the flat portion of the motor shaft. Loosen set screw on blower wheel and reposition if necessary.

12. Spin the blower wheel by hand to verify that the wheel does not rub on the housing.

13. Reinstall blower assembly in furnace.

14. Reinstall 2 screws securing blower assembly to blower deck.

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15. Reconnect blower leads to furnace control. Refer to furnace wiring diagram, and connect thermostat leads if previously disconnected.

NOTE: Be sure to attach ground wire and reconnect blower harness plugs to blower motor.

WARNING

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury or death.

Blower door switch opens 115--v power to control. No component operation can occur unless switch is closed. Caution must be taken when manually closing this switch for service purposes.

16. Downflow or horizontal furnaces with vent pipe through furnace only:

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a. Install and connect short piece of vent pipe inside furnace

to existing vent.

b. Connect vent connector to vent elbow.

17. Turn on electrical supply. If outdoor temperature is below 70_F, turn off circuit breaker to outdoor unit before running furnace in the cooling cycle. Turn outdoor circuit breaker on after completing cooling cycle. (See Fig. 34.) Manually close blower door switch. Use a piece of tape to hold switch closed. Check for proper rotation and speed changes between heating and cooling by jumpering R to G and R to Y/Y2 on furnace control thermostat terminals.

NOTE: If R--W/W1 thermostat terminals are jumpered at the time blower door switch is closed, blower will run for 90 sec before beginning a heating cycle.

a. Performcomponent self--testas shownat the bottom ofthe

SERVICE label, located on the control door.

b. Verify blower is rotating in the correct direction

18. If furnace is operating properly, RELEASE BLOWER DOOR SWITCH. Remove any jumpers or reconnect any disconnected thermostat leads. Replace blower door.

19. Turn on gas supply and cycle furnace through one complete heating cycle. Verify the furnace temperature rise as shown in Adjustments Section. Adjust temperature rise as shown in Adjustments Section.

Cleaning Burners and Flame Sensor

The following items must be performed by a qualified service technician. If the burners develop an accumulation of light dirt or dust, they may be cleaned by using the following procedure:

NOTE: Use a back-up wrench on the gas valve to prevent the valve from rotating on the manifold or damaging the mounting to the burner assembly.

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or service. Follow the operating instructions on the label attached to the furnace.

Refer to Fig. 61.

1. Disconnect power at external disconnect, fuse or circuit breaker.

2. Turn off gas at external shut-off or gas meter.

3. Remove control door and set aside.

4. Turn electric switch on gas valve to OFF.

5. Disconnect the gas pipe from gas valve and remove pipe from the furnace casing.

6. Disconnect the connector harness from gas valve (Modulating only) or remove individual wires from terminals on gas valve (All other models).

7. Disconnect Hot Surface Igniter (HSI) wires from HSI.

8. Disconnect Flame Sensor wire from Flame Sensor.

9. Support the manifold and remove the 4 screws that secure the manifold assembly to the burner assembly and set aside. Note the location of the green/yellow wire and ground terminal.

10. Inspect the orifices in the manifold assembly for blockages or obstructions. Remove orifice and clean or replace orifice.

11. Remove the four screws that attach the top plate of the casing to the furnace.

12. Raise top plate up slightly and prop it up with a small piece of wood or folded cardboard.

13. Support the burner assembly and remove the screws that attach the burner assembly to the heat exchanger cell panel.

14. Remove wires from both rollout switches.

15. Slide one--piece burner out of slots on sides of burner assembly.

16. Remove the flame sensor from the burner assembly.

17. (Optional) Remove the Hot Surface Igniter (HSI) and bracket from the burner assembly.

18. Check igniter resistance. Nominal resistance is 40 to 70 ohms at room temperature and is stable over the life of the igniter.

19. Clean burner with a brush and a vacuum.

20. Clean the flame sensor with fine steel wool (0000 grade). Do not use sand paper or emery cloth.

To reinstall burner assembly:

1. Install the Hot Surface Igniter (HSI) and bracket in burner assembly.

2. Install flame sensor on burner.

3. Align the edges of the one-piece burner with the slots in the burner assembly and slide the burners forward until they are fully seated in the burner assembly.

4. Align the orifices in the manifold assembly with the support rings on the end of the burner.

5. Insert the orifices in the support rings of the burners.

NOTE: If manifold does not fit flush against the burner, do not force the manifold on the burner assembly. The burners are not fully seated forward in the burner assembly. Remove the manifold and check burner positioning in the burner assembly assembly before re-installing the manifold.

6. Attach the green/yellow wire and ground terminal to one of the manifold mounting screws.

7. Install the remaining manifold mounting screws.

8. Check the igniter alignment. See Fig. 55, 56 and 61.

9. Attach the wires to the roll-out switches.

10. Align the burner assembly with the openings in the primary cell inlet panel and attach the burner assembly to the cell panel.

11. Connect the wire for the flame sensor.

12. Connect the wire for the Hot Surface Igniter.

NOTE: Use propane-resistant pipe dope to prevent leaks. Do not use Teflon tape.

13. Install the gas pipe to the gas valve.

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WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

14. Check for gas leaks with a commercially available soap

15. Turn gas on at electric switch on gas valve and at external

16. Turn power on at external disconnect, fuse or circuit break-

17. Run the furnace through two complete heating cycles to

18. Install control door when complete.

Servicing Hot Surface Igniter

The igniter does NOT require annual inspection. Check igniter resistance before removal. Refer to Fig. 55, 56 and 61.

1. Turn off gas and electrical supplies to furnace.

2. Remove control door.

3. Disconnect igniter wire connection.

4. Check igniter resistance. Igniter resistance is affected by

5. Remove igniter assembly.

6. To replace igniter and bracket assembly, reverse items 5a

7. Reconnect igniter harness to the igniter, dressing the igniter

8. Turn on gas and electrical supplies to furnace.

9. Verify igniter operation by initiating control board self--test

10. Replace control door.

Flushing Collector Box and Drainage System

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or service. Follow the operating instructions on the label attached to the furnace.

solution made specifically for the detection of leaks.

shut-off or meter

er.

check for proper operation

temperature. Only check resistance when the igniter is at room temperature.

a. Using an ohm meter, check resistance across both igniter

leads in connector.

b. Cold reading should be between 40 ohms and 70 ohms.

Resistance reading will increase as igniter temperature increases.

a. Using a 1/4--in. driver, removethe two screws securing the

igniter mounting bracket to the burner assembly (See Fig. 61 .)

b. Carefully withdraw the igniter and bracket assembly

through the frontof the burner assembly without striking the igniter on surrounding parts.

c. Inspect igniter for signs of damage or failure.

d. If replacement is required, remove the screw that secures

the igniter on igniter bracket and remove the igniter.

through 5d.

wires to ensure there is no tension on the igniter itself. (See Fig. 61.)

feature or by cycling thermostat.

WARNING

1. Turn off gas and electrical supplies to furnace.

2. Remove control door.

3. Disconnect pressure switch tube from pressure switch port.

NOTE: Ensure the pressure switch tube disconnected from the pressure switch is higher than the collector box opening or water will flow out of tube.

4. Remove the collector box plug from the top port on the upper corner of the collector box. (See Fig. 57)

5. Attach a funnel with a flexible tube to port on the collector box.

6. Flush inside of collector box with water until discharge water from condensate trap is clean and runs freely.

7. Repeat steps 4 thru 6 with middle plug on upper corner of collector box.

8. Remove the pressure switch tube from the collector box.

NOTE:DoNOT blow into tube with tube connected to the pressure switch.

9. Clean pressure switch port on collect box with a small wire. Shake any water out of pressure switch tube.

10. Reconnect tube to pressure switch and pressure switch port.

11. Remove the relief tube from the port on the collector box and the trap.

12. Clean the relief port on collect box and the trap with a small wire. Shake any water out of the tube.

13. Reconnect relief tube to trap and collector box ports.

Cleaning Condensate Drain and Trap

NOTE: If the condensate trap is removed, a new gasket between

the trap and collector box is required. Verify a condensate trap gasket is included in the service kit or obtain one from your local distributor.

1. Disconnect power at external disconnect, fuse or circuit breaker.

2. Turn off gas at external shut-off or gas meter.

3. Remove control door and set aside.

4. Turn electric switch on gas valve to OFF.

5. Disconnect external drain from condensate drain elbow or drain extension pipe inside the furnace and set aside.

6. Disconnect the condensate trap relief hose from collector box port and condensate trap.

NOTE: If condensate has a heat pad attached to the trap, trace the wires for the pad back to the connection point and disconnect the wires for the heat pad.

7. Remove the screw that secures the condensate trap to the collector box, remove the trap and set aside.

8. Remove the trap gasket from the collector box if it did not come off when the trap was removed.

9. Discard the old trap gasket.

10. Rinse condensate trap in warm water until trap is clean.

11. Flush condensate drain lines with warm water. Remember to check and clean the relief port on the collector box.

12. Shake trap dry.

13. Clean port on collector box with a small wire.

To re-install Condensate Drain and Trap:

1. Remove adhesive backing from condensate trap gasket

2. Install gasket on collector box

3. Align the condensate trap with the drain opening on the collector box and secure the trap with the screw

4. Attach the relief hose to the relief port on the condensate trap and collector box.

5. Secure tubing to prevent any sags or traps in the tubing.

6. Connect condensate drain elbow or drain extension elbow to the condensate trap

7. Connect the leads of the condensate heat pad (if used)

8. Connect external drain piping to the condensate drain elbow or drain extension pipe.

9. Turn gas on at electric switch on gas valve and at external shut-off or meter

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10. Turn power on at external disconnect, fuse or circuit breaker.

11. Run the furnace through two complete heating cycles to check for proper operation

12. Install control door when complete.

Checking Heat Pad Operation (If Applicable)

In applications where the ambient temperature around the furnace is 32_F or lower, freeze protection measures are required. If this application is where heat tape has been applied, check to ensure it will operate when low temperatures are present.

NOTE: The Heat Pad, when used, should be wrapped around the condensate drain trap. There is no need to use heat tape within the furnace casing. Most heat tapes are temperature activated, and it is not practical to verify the actual heating of the tape. Check the following:

1. Check for signs of physical damage to heat tape such as nicks, cuts, abrasions, gnawing by animals, etc.

2. Check for discolored heat tape insulation. If any damage or

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discolored insulation is evident, replace heat tape.

3. Check that heat tape power supply circuit is on.

Cleaning Heat Exchangers

The following items must be performed by a qualified service technician.

Primary Heat Exchangers

If the heat exchangers get an accumulation of light dirt or dust on the inside, they may be cleaned by the following procedure:

NOTE: If the heat exchangers get a heavy accumulation of soot and carbon, both the primary and secondary heat exchangers should be replaced rather than trying to clean them thoroughly due to their intricate design. A build--up of soot and carbon indicates that a problem exists which needs to be corrected, such as improper adjustment of manifold pressure, insufficient or poor quality combustion air, improper vent termination, incorrect size or damaged manifold orifice(s), improper gas, or a restricted heat exchanger (primary or secondary). Action must be taken to correct the problem.

1. Turn off gas and electrical supplies to furnace.

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death, or property damage.

3. Disconnect wires or connectors to flame rollout switch, gas valve, igniter, and flame sensor.

4. Using backup wrench, disconnect gas supply pipe from furnace gas control valve.

5. Remove two screws attaching top filler plate and rotate upwards to gain access to screws attaching burner assembly to cell panel.

6. Remove screws attaching burner assembly to cell panel. (See Fig. 61.)

NOTE: Burner cover, manifold, gas valve, and burner assembly should be removed as one assembly.

7. Clean heat exchanger openings with a vacuum and a soft brush. (See Fig. 58.)

NOTE: After cleaning, inspect the heat exchangers to ensure they are free of all foreign objects that may restrict flow of combustion products.

8. Reverse items 6 through 1 for reassembly.

9. Refer to furnace wiring diagram and reconnect wires to flame rollout switch, gas valve, igniter, and flame sensor.

10. Turn on gas and electrical supplies to furnace.

11. Check furnace operation through 2 complete heat operating cycles. Look at burners. Burner flames should be clear blue, almost transparent. (See Fig. 59.)

12. Check for gas leaks.

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

13. Replace main furnace door.

Secondary Heat Exchangers

The condensing side (inside) of the secondary heat exchanger CANNOT be serviced or inspected without complete removal of the heat exchanger assembly. Detailed information on heat exchanger removal can be obtained from your Distributor.

Wiring Diagrams

See Fig. 63 for the Deluxe 4--Way Multipoise Furnace wiring diagrams.

WINTERIZATION

CAUTION

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and install lockout tag before performing any maintenance or service. Follow the operating instructions on the label attached to the furnace.

2. Remove control door.

UNIT AND PROPERTY DAMAGE HAZARD

Failure to follow this caution may result in unit component or property damage.

If the furnace is installed in an unconditioned space where the ambient temperatures may be 32_ F(0_ C) or lower, freeze protection measures must be taken to prevent property or product damage.

Since the furnace uses a condensing heat exchanger, some water will accumulate in the unit as a result of the heat transfer process. Therefore, once it has been operated, it cannot be turned off and left off for an extended period of time when temperatures will reach 32_F(0_C) or lower unless winterized. Follow these procedures to winterize your furnace:

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CAUTION

UNIT COMPONENT DAMAGE HAZARD

Failure to follow this caution may result in damage to the furnace and other property damage.

Do not use ethylene glycol (automotive antifreeze coolant or equivalent). Failure of plastic components may occur.

1. Obtain propylene glycol (RV/swimming pool antifreeze or equivalent).

2. Turn off gas and electrical supplies to your furnace.

3. Remove furnace control door.

4. Remove the top unused rubber plug from the port on the collector box opposite the condensate trap. See Fig. 57.

5. Connect a field supplied 3/8--in. (9.5--mm) ID tube to the open port on the collector box

6. Insert a field supplied funnel into the tube.

7. Pour 1 quart of anti--freeze solution into the funnel/tube. Antifreeze should run through the inducer housing, overfill condensate trap and flow to an open drain.

8. Replace the rubber plug in the port on the collector box.

9. Remove the middle unused rubber plug from the port on the collector box opposite the condensate trap. See Fig. 57

10. Repeat Steps 5 through 8.

11. If a condensate pump is used, check with pump manufacturer to verify pump is safe for use with antifreeze used. Allow pump to start and pump anti--freeze to open drain.

12. Replace main door.

13. When furnace is re--started, flush condensate pump with clear water to check for proper operation before re--starting furnace.

14. Propylene glycol need not be removed before re--starting furnace.

Fig. 57 -- Priming Condensate Trap

(Appearance May Vary)

A11392

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1-1/4-in.

(31.8)

2-1/2-in.

(64.4)

Fig. 55 -- Igniter Position -- Top View

2-in.

3/8-in.

Fig. 56 -- Igniter Position -- Side View

3/16-in.

(2.5 mm +/- .75 mm)

A11405

A11272

A11273

Fig. 58 -- Cleaning Heat Exchanger Cell

Burner Flame

Burner

Manifold

A11461

Fig. 59 -- Burner Flame

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A11347

Fig. 60 -- Blower Assembly

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BURNER SUPT. ASSY

BURNER ASSY

IGNITER

BRACKET, IGNITER

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FLAME ROLLOUT SWITCH

FLAME SENSOR (BELOW BURNER)

Fig. 61 -- Burner Assembly

A11403

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SEYSEYSEY

YES

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Close door switch.

Guide

Is door switch closed?

Troubleshootin

Is circuit breaker closed?

YES

Is there 115V going to switch?

Check for continuity in wire from circuit

breaker to furnace.

Close circuit breaker and go back to

START.

Is 24V present at W /W1, W2, Y1, Y/Y2 or

G thermostat terminals on the furnace

Check room thermostat or

interconnecting cable.

control?

Disconnect all the thermostat wires from

the furnace control.

Does the problem repeat when using a

jumper wire?

The thermostat is not c ompatible with the

furnace control. Either install a ballast

resistor, connect the Com24V thermostat

terminal to the thermostat, or replace the

thermostat.

YES

Replace door switch.

Replace transformer.

Does the control respond to W/W1, W2,

Y1, Y/Y2, and G (24V) thermostat

signals?

Run system through a minimum-heat,

maximum-heat, or cooling cycle to check

operation. Status codes are erased after

72 hours or can be m anually erased by

putting setup switch SW1-1 in the ON

position and jumpering R, W/W1, and

Y/Y2 simultaneously until status code

#11 is flashed.

Replace furnace control.

ONON

YES

Is the re 115 V at L1 and L2?

ONON

Is there 24V at SEC-1 and SEC-2?

YES

Replace furnace control.

Check for correct line volt age polarity. If

units are twinned, check for proper low-

voltage (24V) transformer phasing.

YES

To recall previous status codes disconnect the R

thermostat connection, reset power, an d put setup

switch SW1-1 in the ON position. The AMBER LED

will flash the status codes in the order of occ urrence.

Record status codes until status code #11 flashes (1

short and 1 long flash). After status code #11

flashes the status codes will repeat. Status codes

are erased after 72 hours or can be manually erased

by putting setup switch SW1-1 in the ON position

and jumpering R, W/W1, and Y/Y2 simultaneously

until status code #11 is flashed. When done put

setup switch SW1-1 in the O FF position.

Was there a previous status code o ther

than #11?

YES

START

Is AMBER LED status light on?

Is AMBER LED status light blinking

rapidly without a paus e?

Is AMBER LED status light blinking

ON/OFF slowly with a combination of

short and long flashes?

Determine status code. The status code

is a 2 digit number with the first digit

determined by the number of short

flashes and the second digit by the

number of long flashes?

Go to section below for the status code

that was flashed.

A11290A

Fig. 62 -- Troubleshooting Guide

Page 77

LOCKOUT Auto-reset

45 CONTROL CIRCUITRY

open.

after 1 hour lockout due

to:

- Gas valve relay stuck

- Flame ci rcuit failure.

- Soft ware check error.

Reset power to clear

lockout. Replace control

if code repeats.

Replace furnace control.

Check for continuity in the

harness and igniter. Replace

defective component.

Check that all gas valves are

Check connections. If OK,

turned on. Replace valve.

replace control.

or rough ignition.

Check for:

- Inadequate flame carryover

Allow unit to drop to min-heat,

- Low inlet gas pressure.

and check manifold pres sure.

- Proper firing rate.

Check connections and r etry.

If current is near typical value

(4.0-6.0 nominal) and burners

will not stay on, repeat check

in max-heat. If burners will

still not stay on replace

control. If burners operate in

max-heat then switch to

intermediate-heat, check

manifold pressure. If OK,

check burner carryover and

Repeat test to check for

intermittent operation.

flame sensor location.

43 LOW OR MEDIUM PRESSURE SWITCH

32 LOW PRESSURE SWITCH DID NOT

YES

987MA

OPEN W HILE MEDIUM OR H IGH

CLOSE OR REOPENED – If opens during

tubing.

PRESSURE SW ITCH IS CLOS ED -

Check for:

- Low or Med press. switch stuck open.

- Disconnec ted or obstructed pressure

blower on-delay period, blower will come

on for the selected blower off-delay. If

opens within 5 minutes af ter ignition the

next heating cycle will be restricted to

maximum-heat. Check for:

pipe.

Unplug igniter harness from control and

repeat component test by turning setup

switch SW1-6 OFF and then back ON.

Check for 115V between pin 3 and

NEUTRAL-L2 on the control. Was 115V

present for the 15 second peri od?

Reconnect the R thermos tat lead and set

thermostat to call for heat. Connect

voltmeter across gas valve BLUE and

GREEN/YELLOW wires. Does gas valve

receive 24V?

Does gas valve open and allow gas to

flow?

Do the main burners ignite?

- Low inlet gas pressure (if LGPS used).

- Plugged c ondensate drain.

- W ater in vent piping, possible sagging

- Improper pressure switch wiring.

Do the main burners stay on?

Repeat call for heat and check flame

sensor current during trial for ignition

period. Is the DC microamps below 0.5?

71% of maximum

compartment.

tubing.

setup switch SW1-3 ON to boost

inducer speed

- Proper v ent sizing.

- Air leak between vestibule and blower

- Low inlet gas pressure (if LGPS used).

-Restrictedvent.

- Disconnected or obstructed pressure

- Defective or miswired press ure switches

- Excessive wind. If problem persists turn

pipe.

- Plugged c ondensate drain.

- W ater in vent piping, possible saggin g

33 LIMIT CIRCUIT FAULT – Indicates the

limit or a flame rollout switch is open or the

rate. Blo wer will run for 4 min. or until

open switch remakes whichever is longer.

If open longer than 3 min., code changes

to lockout #13. If open less than 3 min.

status code #33 continues to flash until

furnace is operating in maximum-heat only

mode due to 2 successive limit trips while

operating at any rate <

blower shuts off. Flame rollout switch

gas input adjustment.

requires manual reset. Check for:

- Loose blo wer wheel.

- Defective switch or connections.

- Improper minimum- or maximum-heat

- Improper limit switch or no limit gasket.

- Dirty filter or restricted d uct system.

not sensed during the trial for ignition

period, the control will repeat the ignition

34 IGNITION PROVING FAILURE – If flame is

Clean flame sensor with fine steel wool

and recheck current. Nominal current is

4.0 to 6.0 microamps.

Is current near typical value? Replace electrode.

Will main burners ignite and stay on? Replace furnace control.

Fixed.

YES

sequence 3 more times before lockout #14

occurs. If flame signal is lost during the

blower on-delay period, blower will come on

for the selected blower off-delay. Check

the following items first before proceeding

connected to furnace s heet metal.

to the next step.

- Gas valve tu rned off.

- GREEN/YELLOW wire MUST be

- Flame sensor must not be grounded.

To determine whether the problem is in the

gas valve, igniter, or flame sensor the

system can be operated in component test

mode. To check the igniter remove the R

thermostat connection from the control,

reset power, and put setup switch SW1-6 in

the ON position to start the component test.

Does the igniter glow orange/white by the

- Manual shut-off valve.

end of the 15 second warm-up period?

erased after 72 hours or can be manuall y

erased by putting setup switch SW 1-1 in

the ON position and jumperi ng R, W/W1,

and Y/Y2 simultaneously until status code

#11 is flashed. Run system through a

minimum-heat, maximum-heat, or cooling

cycle to check system.

(115V OR 24V) – Normal operation.

Blower runs for 90 sec onds, if unit is

powered up during a c all for heat (R-

W/W1 closed) or when (R-W /W1 opens)

during the blower on- delay period.

11 NO PREV IOUS CODE – Status codes are

12 BLOWER ON AFTER POWER UP –

13 LIMIT CIRCUIT LOCKOUT – Lockout

wiring including thermostat leads.

Disconnect thermostat leads to isolate

occurs if the limit or flame rollout switch is

open longer than 3 minutes or 10

successive limit trips occurred during

maximum-heat. Control will auto-reset

after 3 hours. See code 33.

ignite gas and prove flame i n 4 attempts.

Control will auto-reset after 3 hours. See

status code 34.

the blower failed to reach 250 RPM or the

blower failed to communicate within 30

seconds after being tur ned ON in two

successive heating cycles. Control will

14 IGNITION LOCKOUT – System failed to

15 BLOWER MOTOR LOCKOUT – Indicates

power a nd wait 5 mi nutes to retry. Check

for:

- Stuck closed gas valve relay on control.

- Miswire or short to gas valve BLUE wire.

Flame is proved while gas valv e is de-

energized. Inducer will run until fault is

cleared. Check for:

- Stuck ope n or leaky gas valve.

auto-reset after 3 hours. See code 41.

21 GAS HEATING LOCKOUT – Turn off

22 ABNORMAL FLAME-PROVING SIGNAL

Check for:

- Obstructed pressure tube.

- Pressure switch stuck closed.

23 PRESSURE SW ITCH DID NOT OPEN –

24 SECONDARY VOLTAGE FUSE IS OPEN

Check for:

- Short circuit in secondary voltage (24V)

A11290B

short circuit.

Page 78

Youhaveanopenwireorbad

terminal on either the BLACK or

WHITE power leads between

the furnace control and the

blower motor. If you have a

power choke disconnect it and

check continuity.

Youhaveanopenwireorbad

terminal on either the RED or

GREEN wire between the

furnace control and the blower

motor.

YES

Is there 5-VDC at PL3-3

YELLOW (+) and PL3-2

GREEN (-)?

Youhaveanopenwireorbad

terminal on the YELLOW wire

between the furnace control and

the blower motor.

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YES

Turn power back on. Is there 115VAC at

PL14-5 and PL14-4?

Is there 12-VDC at PL13-1 RED (+) and

PL13-4 GREEN (-)?

Is there 12-VDC at P L3-1 RED (+) and

PL3-2 GREEN (-)?

YES

Replace the furnace control.

Is there 5-VDC at PL13-2 YELLOW (+)

and PL13-4 GREEN (-)?

The voltage just measured should be

very stable and should not fluctuate more

than .02-VDC. If the voltage fluctuates

more than this get a different voltmeter

before proceeding.

Turn power off, reconnect PL13 and

PL14 to the blower motor, then turn

power back on. Connect a DC voltmeter

across PL3-3 YELLOW (+) and PL3-2

Turn power off, disconnect PL13 and

PL14 from the blower motor, then turn

power back on. Connect a DC voltmeter

across PL13-3 BLUE (+) and PL13-4

GREEN (-). The voltage should be near

0-VDC but it will fluctuate briefly several

times a second. If you have an analog

voltmeter the needle will briefly go high

several times a second. If you have a

digital voltmeter with a bar graph it will

show a large change in magnitude on the

bar graph several times a second. If you

have a standard digi tal voltmeter it will

show a brief fluctuation in voltage and the

magnitude may vary depending on the

GREEN (-). Does the voltage fluctuate

more than it did in the previous step?

voltmeter used.

YES

blower failed to reach 250 RPM or the

blower failed to communicate within the

prescribed time limits. Thirty seconds

after being turned ON or ten seconds

during steady-state operation. Turn power

off and check the following items first

before proceeding to the next step.

41 BLOWER MOTOR FAULT – Indicates the

- Rubbing blower wheel.

motor.

- Loose blower wheel.

- Wiring from furnace control to blower

Remove the R thermostat connection from

the furnace control, disconnec t both

connectors from the blower motor PL13

and PL14. Does the blower wheel turn

freely?

Replace the blower control module attached to

the blower motor. Follow the instructions with

the blower control module to make sure the

entire blower motor does not need to be

replaced.

You have an open wire or bad terminal on the

BLUE wire between the furnace control and the

blower motor.

Replace the furnace control.

Connect a DC voltmeter across PL3-4 BLUE

(+) and PL3-2 GREEN (-). Does the voltage

fluctuate as described two steps back?

Does the voltage fluctuate as described in the

previous step?

Replace the blower control module attached to

the blower motor. Follow the instructions with

the blower control module to make sure the

entire blower motor does not need to be

replaced.

YES

no valid model stored in permanent

memory. This will happen if you forget

to install the model plug PL4 on a

SETUP ERROR – If status code 25 only

flashes 4 times on power-up the control is

missing its model plug PL4 and is

defaulting to the model selection stored in

memory. If status code 25 flashes

continuously it could indicate any of the

following:

- Model plug PL4 is missing and there is

25 INVAL ID MODEL SE LECTION OR

service replacement control.

- Thermostat call with SW 1-1 ON.

- Thermostat call with SW 1-6 ON.

Need modulating board with software

-SW1-1andSW1-6bothON.

version V17 or later.

- Two different furnace models twinned.

- Service replacement control is incorrect.

PRESSURE SWITCH, OR PSR RELAY

DID NOT CLOSE OR REOPENED -

Check for:

- PSR relay may be defective.

- See status code 32.

modulating gas valve failed to respond to

a command from the furnace control or

31 MEDIUM PRESSURE SWITCH, HIGH

35 GAS VALVE FAULT – Indicates the

ORANGE wire at gas valve or PL8

connections.

inducer motor has not started within 20

seconds after a call for heat, the inducer

motor RPM is outside its valid range of

operation, or the inducer RPM signal was

lost for 5 seconds during operation.

Check for:

- Proper vent sizing.

-Failedinducermotor.

- Restricted combustion air supply.

power to the gas valve electronics was

interrupted. Check for:

- Intermittent RED, YELLOW , or

42 INDUCER MOTOR FAULT – Indicates the

- Improper motor wiring.

A11290C

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SEQUENCE OF OPERATION

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in intermittent unit operation.

Furnace control must be grounded for proper operation or control will lock out. Control is grounded through green/yellow wire routed to gas valve and burner box screw.

Using the schematic diagram (See Fig. 63), follow the sequence of operation through the different modes. Read and follow the wiring diagram very carefully!!

NOTE: If a power interruption occurs during a call for heat (W/W1 or W/W1-and-W2), the control will start a 90-second blower-only ON period two seconds after power is restored, if the thermostat is still calling for gas heating. The amber LED light will flash code 12 during the 90-second period, after which the LED will be ON continuous, as long as no faults are detected. After the 90-second period, the furnace will respond to the thermostat normally.

The blower door must be installed for power to be conducted through the blower door interlock switch ILK to the furnace control CPU, transformer TRAN, inducer motor IDM, blower motor BLWM, hot surface igniter HSI, and gas valve GV.

Communicating Control and Modulating Heating (Adaptive Mode)

Best comfort will be attained when a communicating wall control is used with this product. Wiring and set--up instructions are provided with the communicating control. See the furnace data sheet accessory section for help in selecting the appropriate communicating control for this furnace.

When a communicating control is used, the furnace will modulate through its full operation range, or can be limited via the minimum and maximum cfm configurations.

Operation of the furnace at the beginning and end of each heating cycle will be the same as detailed below in the Single--Stage Thermostat section EXCEPT that the communicating control will send modulating rate command signals through the communication bus rather than energizing the 24--v thermostat terminals. Note that the R to W/W1 circuit signal will be controlled by the COMMR relay on the furnace control. See the wiring diagram in Fig. 63 .

Single-Stage Thermostat and Modulating Heating (Adaptive Mode)

See Fig. 34 and 35 for thermostat connections. NOTE: Minimum-heat only switch SW1-2 selects the

minimum-heatonly operation mode when ON. Intermediate-heat only switch SW4-2 selects intermediate-heat only operation mode when ON. If both switches are ON the furnace control will default to intermediate-heat. If either or both switches are ON, the furnace control will operate at two-stages only as referenced in Two Stage Thermostat section below. If both switches are OFF the furnace control will operate in the adaptive heating mode in response to a call for heat. (See Fig. 54.) When the W2 thermostat terminal is energized it will always cause maximum-heat operation as long as the R to W circuit is closed, regardless of the setting of the minimum-heat or intermediate-heat only switches.

This furnace can operate as a modulating furnace with a single-stage thermostat because the furnace control CPU includes a programmed adaptive sequence of controlled operation, which selects a modulated rate between minimum- and maximum-heat.

This selection is based upon the stored history of the length of previous gas-heating periods of the single-stage thermostat.

The furnace will start up in either intermediate-, or maximum-heat. The furnace will transition and operate at minimum-heat or the calculated modulating rate after starting and operating for 45 seconds at intermediate-heat. The furnace control CPU defaults to minimum-heat on the first thermostat cycle and calculates the modulating rate that the furnace should run at for 19 minutes on subsequent heat cycles.

If the power is interrupted, the stored modulating rate is erased and the furnace control will select intermediate-heat for 45 seconds, minimum-heat for 19 minutes and then switch to maximum-heat, as long as the thermostat continues to call for heat. The furnace control CPU then uses this information to calculate the modulating rate the furnace will operate at on the next heating cycle. If the calculated modulating rate is between 40% - 99% then the furnace control CPU will operate for 45 seconds at intermediate-heat, and then operate at the calculated modulating rate for up to 19 minutes and then switch to maximum-heat as long as the thermostat continues to call for heat. If the calculated modulating rate is 100% then the furnace control will only operate at maximum-heat until the thermostat is satisfied.

The wall thermostat ”calls for heat”, closing the R to W circuit. The furnace control CPU performs a self-check, verifies the low, medium, and high pressure switch contacts LPS,MPS, and HPS are open, then de-energizes the PSR relay to close the NC contact.

1. Inducer Prepurge Period - The furnace control CPU turns

on inducer motor IDM and slowly increases the inducer motor speed. After the low pressure switch LPS closes the furnace control CPU continues to increase the inducer motor speed until the medium pressure switch MPS closes. When the medium pressure switch MPS closes, inducer motor RPM is noted by the furnace control CPU, and a 25-second prepurge period begins. The RPM is used to evaluate vent system resistance. This evaluation is then used to determine the required RPM necessary to operate the inducer motor during pre-purge, the first 45 seconds of intermediate-heat, or any modulating rate that the furnace will transition to after the blower on-delay is completed.

NOTE: The heat cycle can start in either intermediate- or maximum-heat. If a maximum-heat cycle is initiated, the furnace control CPU will continue to increase the inducer motor speed after the medium pressure switch MPS closes. When the medium pressure switch closes, inducer motor RPM is noted by the furnace control CPU, and a 25-second prepurge period begins. The RPM is used to evaluate vent system restriction. This evaluation is then used to determine the required RPM necessary to operate the inducer motor in maximum-heat pre-purge, or maximum-heat. The high pressure switch HPS should be closed before ignition but the furnace control ignores this input until after ignition occurs.

2. Igniter Warm-Up - At the end of the prepurge period, the

Hot-Surface Igniter HSI is energized for a 17-second igniter warm-up period

3. Trial-For-Ignition Sequence - When the igniter warm-up

period is completed the main gas valve relay contact GVR closes to energize the gas valve solenoid GV (pin 5). The gas valve solenoid GV (pin 5) permits gas flow to the burners where it is ignited. Five seconds after the GVR closes, a 2-second Flame-Proving period begins. The HSI igniter will remain energized until flame is sensed or until the 2-second flame proving period begins.

4. Flame-Proving - When the burner flame is proved at the

flame-proving sensor electrode FSE, the furnace control CPU begins the blower-ON delay period and continues to hold the gas valve GV (pin 5) open. If the burner flame is not proved within two seconds, the furnace control CPU will close the gas valve GV (pin 5), and the furnace control

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CPU will repeat the ignition sequence for up to three more Trials-For-Ignition before going to Ignition-Lockout. Lock- out will be reset automatically after three hours, or by momentarily interrupting 115 vac power to the furnace, or by interrupting 24 vac power at SEC1 or SEC2 to the furnace control CPU (not at W/W1, G, R, etc.). If flame is proved when flame should not be present, the furnace control CPU will lock out of Gas-Heating mode and operate the inducer motor IDM at full speed until flame is no longer proved.

5. Inducer Speed Change - If the cycle starts in intermedi-

ate-heat, the furnace control CPU reduces the inducer speed slightly after flame sense. If cycle starts in maximum-heat, the furnace control CPU increases the inducer speed after flame sense.

6. Blower-On delay — If the burner flame is proven, the

blower-ON delay for intermediate-heat and maximum-heat are as follows: Intermediate-heat - 45 seconds after the gas valve GV (pin

5) is opened the blower motor BLWM is turned ON at the modulating heat airflow. Maximum-heat - 25 seconds after thegas valve GV (pin 5) is opened the BLWM is turned ON at maximum-heat airflow. Simultaneously, the humidifier terminal HUM and electronic air cleaner terminal EAC-1 are energized and remain energized throughout the heating cycle.

7. Switching from Intermediate-Heat to a Low Range In- put - If the furnace control CPU switches from intermediate-heat to a low range input (low range input is an input rate less than or equal to 51% of full rate), the furnace control CPU will turn the blower ON or switch to the modulating heat airflow, energize the PSR relay to open the NC contact, and slowly decrease the inducer motor speed to the desired inducer RPM.

Switching from a Intermediate-Heat to a Medium Range Input - If the furnace control CPU switches from

intermediate-heat to a different medium range input (medium range input is an input rate between 52% and 71% of full rate), the furnace control CPU will turn the blower ON or switch to the modulating heat airflow, and continue to maintain the inducer motor speed or change it further if required.

Switching from a Intermediate-Heat to a High Range Input - If the furnace control CPU switches from intermedi-

ate-heat to a high range input (high range input is an input rate greater than or equal to 72% of full rate), the furnace control CPU will turn the blower ON or switch to the modulating heat airflow, and increase the inducer motor speed to the desired inducer motor RPM. Switching from Low Range Input to Maximum-Heat - If the furnace control CPU switches from a low range input to maximum-heat, the furnace control CPU will de-energize the PSR relay to close the NC contact and slowly increase the inducer motor speed until the medium pressure switch MPS closes. When the medium pressure switch MPS closes the inducer motor RPM is noted by the furnace control CPU. The RPM is used to evaluate vent system resistance. This evaluation is then used to determine the required RPM necessary to operate the inducer motor at maximum-heat. The blower motor BLWM will transition to maximum-heat airflow five seconds after the furnace control CPU switches from a low range input to maximum-heat. As the inducer RPM increases, the high pressure switch HPS should close.

Switching from Medium Range Input to Maximum-Heat - If the furnace control CPU switches from medi-

um range input to maximum-heat, the furnace control CPU will increase the inducer motor speed to the maximum-heat

inducer motor RPM. The blower motor BLWM will transition to the maximum-heat airflow five seconds after the furnace control CPU switches from a medium range input to maximum-heat. As the inducer RPM increases, the high pressure switch HPS should close.

8. Blower-Off Delay — When the thermostat is satisfied, the

R to W circuit is opened, de-energizing the gas valve GV (pin 5), stopping gas flow to the burners, and humidifier terminal HUM. The inducer motor IDM will remain energized fora 15-second post-purge period. The blower motor BLWM and air cleaner terminal EAC-1 will remain energized at minimum-heat airflow or transition to minimum-heat airflow for 90, 120, 150, or 180 seconds (depending on selection at blower-OFF delay switches). The furnace control CPU is factory-set for a 120-second blower- OFF delay.

Two--Stage Thermostat and Modulating Heating (Adaptive Mode)

Operation of Modulating Heating (Adaptive Mode; SW1--2 and SW4--2 are both OFF) with a two--stage thermostat is the same as with a single--stage thermostat, EXCEPT for the following:

If the two--stage thermostat R--W2 circuit closes along with the R to W/W1 circuit, while the furnace is operating at any capacity less than maximum, the furnace will switch to the maximum heating capacity. At this point, the furnace control heating algorithm is overridden and the two--stage thermostat takes control of staging until BOTH R to W/W1 and R to W2 circuits are opened.

The furnace with transition back to the lower heating capacity if the two--stage thermostat opens the R--W2 circuit, but leaves R to W/W1 circuit closed. The furnace control will continue to follow the commands from the two--stage thermostat for W/W1 and W2, until the R to W/W1 circuit is opened.

After the two--stage thermostat opens both the R to W/W1 and R to W2 circuits, the adaptive algorithm will set the beginning capacity of the next heating cycle to the same value as the heating cycle that most recently completed.

Two-Stage Thermostat and Two-Stage Minimum/Maximum Heating

See Fig. 34 and 35 for thermostat connections. NOTE: In this mode, the minimum-heat only switch SW1-2 must

be ON to select the minimum-heat only operation mode in response to closing the thermostat R to W1 circuit. Closing the thermostat R to W1-and-W2 circuits always causes maximum-heat operation, regardless of the setting of the minimum-heat only switch.

The furnace will start up in either intermediate-, or maximum-heat. The furnace will operate in minimum-heat after starting and operating for 1 minute at intermediate-heat before transitioning to minimum-heat.

The wall thermostat ”calls for heat”, closing the R to W1 circuit for minimum-heat or closing the R to W1-and-W2 circuits for maximum-heat. The furnace control performs a self-check, and verifies the low, medium and high pressure switch contacts LPS, MPS and HPS are open, then de-energizesthe PSR relay to close the NC contact.

The start up and shut down functions and delays described above apply to the 2-stage minimum/maximum heating mode as well, except for switching from maximum- to minimum-heat.

1. Switching from Maximum- to Minimum-Heat —Ifthe

thermostat R to W2 circuit opens, and the R to W1 circuit remains closed, the furnace control CPU will gradually decrease the inducer motor speed to the required intermediate-heat RPM. When the inducer motor IDM reduces pressure sufficiently, the high pressure switch HPS will open and the gas rate will be changed to intermediate-heat. The gas valve solenoid GV (pin 5) will remain energized aslong as the low pressure switch LPS remains closed. When the

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inducer motor speed gets within 15% of the required intermediate-heat RPM the furnace control CPU will start a 5 second blower airflow change delay. After the 5 second blower airflow change delay is completed the blower airflow will transition to minimum-heat airflow. At this point the furnace control CPU will energize the PSR relay to open the NC contact and slowly decrease the inducer motor speed to the required minimum-heat RPM. When the PSR relay is energized and the NC contact opens the furnace control CPU will reduce the gas rate to minimum-heat RPM.

Two-Stage Thermostat and Two-Stage Intermediate/ Maximum Heating

See Fig. 34 and 35 for thermostat connections NOTE: In this mode the intermediate-heat only switch SW4-2

must be ON to select the intermediate-heat only operation mode in response to closing the thermostat R to W1 circuit. Closing the thermostat R to W1-and-W2 circuits always causes maximum-heat operation, regardless of the setting of the intermediate-heat only switch.

The wall thermostat ”calls for heat”, closing the R to W1 circuit for intermediate-heat or closing the R to W1-and-W2 circuits for maximum-heat. The furnace control performs a self-check, and verifies the low, medium and high pressure switch contacts LPS, MPS and HPS are open , then de-energizes the PSR relay to close the NC contact.

The start up and shut down functions and delays described above apply to the 2-stage intermediate/maximum heating mode as well, except for switching from maximum- to intermediate-heat.

1. Switching from Maximum- to Intermediate-Heat — If the thermostat R to W2 circuit opens, and the R to W1 circuit remains closed, the furnace control CPU will gradually decrease the inducer motor speed to the required intermediate-heat RPM. When the inducer motor IDM reduces pressure sufficiently, the high pressure switch HPS will open and the gas rate will be changed to intermediate-heat. When the inducer motor speed gets within 15% of the required intermediate-heat RPM the furnace control CPU will start a 5 second blower airflow change delay. After the 5 second blower airflow change delay is completed the blower airflow will transition to intermediate-heat airflow.

Cooling Mode

The thermostat “calls for cooling.”

1. Single-Speed Cooling

See Fig. 34 and 35 for thermostat connections. The thermostat closes the R to G-and-Y circuits. The R to Y circuit

starts the outdoor unit, and the R to G-and-Y/Y2 circuits start the furnace blower motor BLWM on cooling airflow. Cooling airflow isbasedontheA/CselectionshowninFig.54.

The electronic air cleaner terminal EAC-1 is energized with 115 vac when the blower motor BLWM is operating. When the thermostat is satisfied, the R to G-and-Y circuits are opened. The outdoor unit will stop, and the furnace blower motor BLWM will continue operating at cooling airflow for an additional 90 seconds. Jumper Y/Y2 to DHUM to reduce the cooling off-delay to 5 seconds. (See Fig. 34.)

2. Single-Stage Thermostat and Two-Speed Cooling (Ad- aptive Mode)

See Fig. 34 and 35 for thermostat connections. This furnace can operate a two-speed cooling unit with a

single-stage thermostat because the furnace control CPU includes a programmed adaptive sequence of controlled operation, which selects low-cooling or high-cooling operation. This selection is based upon the stored history of the length of previous cooling period of the single-stage thermostat.

NOTE: The air conditioning relay disable jumper ACRDJ must be connected to enable the adaptive cooling mode in response to a call for cooling. (See Fig. 34.) When in place the furnace control CPU can turn on the air conditioning relay ACR to energize the Y/Y2 terminal and switch the outdoor unit to high-cooling.

The furnace control CPU can start up the cooling unit in either low- or high-cooling. If starting up in low-cooling, the furnace control CPU determines the low-cooling on-time (from 0 to 20 minutes) which is permitted before switching to high-cooling.

If the power is interrupted, the stored history is erased and the furnace control CPU will select low-cooling for up to 20 minutes and then energize the air conditioning relay ACR to energize the Y/Y2 terminal and switch the outdoor unit to high-cooling, as long as the thermostat continues to call for cooling. Subsequent selection is based on stored history of the thermostat cycle times. The wall thermostat “calls for cooling”, closing the R to G and- Y circuits. The R to Y1 circuit starts the outdoor unit on low-cooling speed, and the R to G-and-Y1 circuits starts the furnace blower motor BLWM at low-cooling airflow which is the true on-board CFselectionasshowninFig.54.

If the furnace control CPU switches from low-cooling to high cooling, the furnace control CPU will energize the air conditioning relay ACR. When the air conditioning relay ACR is energized the R to Y1-and-Y2 circuits switch the outdoor unit to high-cooling speed, and the R to G-and-Y1- and-Y/Y2 circuits transition the furnace blower motor BLWM to high-cooling airflow. High-cooling airflow is based on the A/C selection shown in Fig.

54. NOTE: When transitioning from low-cooling to high-cooling the

outdoor unit compressor will shut down for 1 minute while the furnace blower motor BLWM transitions to run at high-cooling airflow.

The electronic air cleaner terminal EAC-1 is energized with 115 vac whenever the blower motor BLWM is operating.

When the thermostat is satisfied, the R to G-and-Y circuit are opened. The outdoor unit stops, and the furnace blower BLWM and electronic air cleaner terminal EAC-1 will remain energized for an additional 90 seconds. Jumper Y1 to DHUM to reduce the cooling off-delay to 5 seconds. (See Fig. 34.)

3. Two Stage Thermostat and Two-Speed Cooling

See Fig. 34 and 35 for thermostat connections. NOTE: The air conditioning relay disable jumper ACRDJ must

be disconnected to allow thermostat control of the outdoor unit staging. (See Fig. 34.)

The thermostat closes the R to G-and-Y1 circuits for low cooling or closes the R to G-and-Y1-and-Y2 circuits for high cooling. The R to Y1 circuit starts the outdoor unit on low cooling speed, and the R to G-and-Y1 circuit starts the furnace blower motor BLWM at low-cooling airflow which is the true on-board CF selection as shown in Fig. 54. The R to Y1-and-Y2 circuits start the outdoor unit on high-cooling speed, and the R to G-and-Y/Y2 circuits start the furnace blower motor BLWM at high-cooling airflow. High-cooling airflow is based on the A/C selection shown in Fig.

54. The electronic air cleaner terminal EAC-1 is energized with 115

vac whenever the blower motor BLWM is operating. When the thermostat is satisfied, the R to G-and-Y1 or R to

G-and-Y1-and-Y2 circuits are opened. The outdoor unit stops, and the furnace blower BLWM and electronic air cleaner terminal EAC-1 will remain energized for an additional 90 seconds. Jumper Y1 to DHUM to reduce the cooling off-delay to 5 seconds. (See Fig. 54.)

4. Dehumidification Mode

See Fig. 34 and 35 for thermostat connections. The dehumidification output, D or DHUM on the Thermostat

should be connected to the furnace control thermostat terminal

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Page 82

DHUM. When there is a dehumidify demand, the DHUM input is activated, which means 24 vac signal is removed from the DHUM input terminal. In other words, the DHUM input logic is reversed. The DHUM input is turned ON when no dehumidify demand exists. Once 24 vac is detected by the furnace control, dehumidification capability is activated. If the DHUM input is removed for more than 48 hours, the furnace control reverts back to non-dehumidification mode.

The cooling operation described above in the Cooling Mode section also applies to Dehumidification Mode. The exceptions are listed below:

a. Low cooling – When the R to G-and-Y1 circuit is closed

and there is a demand for dehumidification, the furnace blowermotor BLWM willdrop theblower airflow to 86% of low cooling airflow which is the true on-board CF

selectionasshowninFig.54.

b. High cooling– WhentheR toG-and Y/Y2circuit is closed

and there is a demand for dehumidification, the furnace blowermotor BLWM willdrop theblower airflow to 86%

987MA

of high-cooling airflow. High-cooling airflow is based on the A/C selection shown in Fig. 54.

c. Cooling off-delay – When the “call for cooling” is

satisfied and there is a demand for dehumidification, the cooling blower-off delay is decreased from 90 seconds

to 5 seconds.

Super Dehumidify Mode

Super-Dehumidify mode can only be entered if the furnace control is in the Dehumidification mode and there is a demand for dehumidification. The cooling operation described in Cooling Mode section above also applies to Super Dehumidify Mode. The exceptions are listed below:

1. Low cooling –WhentheRtoY1circuitisclosed,RtoG circuit is open, and there is a demand for dehumidification, the furnace blower motor BLWM will drop the blower airflow to 65% of low-cooling airflow for a maximum of 10 minutes each cooling cycle or until the R to G circuit closes or the demand for dehumidification is satisfied. Low-cooling airflow is the true on-board CF selection as shown in

Fig. 54.

2. High cooling – When the R to Y/Y2 circuit is closed, R to G circuit is open, and there is a demand for dehumidification, the furnace blower motor BLWM will drop the blower airflow to 65% of high-cooling airflow for a maximum of 10 minutes each cooling cycle or until the R to G circuit closes or the demand for dehumidification is satisfied. High-cooling airflow is based on the A/C selection shown

in Fig. 54.

3. Cooling off-delay – When the “call for cooling” is satisfied and there is a demand for dehumidification, the cooling blower-off delay is decreased from 90 seconds to 5 seconds.

Continuous Blower Mode

When the R to G circuit is closed by the thermostat, the blower motor BLWM will operate at continuous blower airflow. Continuous blower airflow selection is initially based on the CF selection shown in Fig. 54. Factory default is shown in Fig. 54. Terminal EAC-1 is energized as long as the blower motor BLWM is energized.

During a call for heat, the furnace control CPU will transition the blower motor BLWM to continuous blower airflow, minimum-heat airflow, or the mid-range airflow, whichever is lowest. The blower motor BLWM will remain ON until the main burners ignite then shut OFF and remain OFF for the blower-ON delay (45 seconds in intermediate heat, and 25 seconds in maximum-heat), allowing the furnace heat exchangers to heat up more quickly, then restarts at

the end of the blower-ON delay period at modulating or maximum-heat airflow respectively.

The blower motor BLWM will revert to continuous-blower airflow after the heating cycle is completed. When the thermostat satisfies, the furnace control CPU will drop the blower motor BLWM to minimum-heat airflow during the selected blower-OFF delay period before transitioning to continuous-blower airflow.

When the thermostat “calls for low-cooling”, the blower motor BLWM will operate at low-cooling airflow. When the thermostat is satisfied, the blower motor BLWM will operate an additional 90 seconds at low-cooling airflow before transitioning back to continuous-blower airflow.

When the thermostat “calls for high-cooling”, the blower motor BLWM will operate at high cooling airflow. When the thermostat is satisfied, the blower motor BLWM will operate an additional 90 seconds at high-cooling airflow before transitioning back to continuous-blower airflow.

When the R to G circuit is opened, the blower motor BLWM will continue operating for an additional 5 seconds, if no other function requires blower motor BLWM operation.

Continuous Blower Speed Selection from Thermostat

To select different continuous-blower airflows from the room thermostat, momentarily turn off the FAN switch or push button on the room thermostat for 1-3 seconds after the blower motor BLWM is operating.

The furnace control CPU will shift the continuous-blower airflow from the factory setting to the next highest CF selection airflow as shown in Fig. 54. Momentarily turning off the FAN switch again at the thermostat will shift the continuous-blower airflow up one more increment. If you repeat this procedure enough you will eventually shift the continuous blower airflow to the lowest CF selection as shown in Fig. 54. The selection can be changed as many times as desired and is stored in the memory to be automatically used following a power interruption.

Heat Pump

See Fig. 34 and 35 for thermostat connections. When installed with a heat pump, the furnace control automatically changes the timing sequence to avoid long blower off times during demand defrost cycles. Whenever W/W1 is energized along with Y1 or Y/Y2, the furnace control CPU will transition to or bring on the blower motor BLWM at cooling airflow, minimum-heat airflow, or the mid-range airflow, whichever is lowest. The blower motor BLWM will remain on until the main burners ignite then shut OFF and remain OFF for 25 seconds before coming back on at modulating heat airflow. When the W/W1 input signal disappears, the furnace control begins a normal inducer post-purge period while changing the blower airflow. If Y/Y2 input is still energized the furnace control CPU will transition the blower motor BLWM airflow to cooling airflow. If Y/Y2 input signal disappears and the Y1 input is still energized the furnace control CPU will transition the blower motor BLWM to low-cooling airflow. If both the Y1 and Y/Y2 signals disappear at the same time, the blower motor BLWM will remain on at minimum-heat airflow for the selected blower-OFF delay period. At the end of the blower-OFF delay, the blower motor BLWM will shut OFF unless G is still energized, in which case the blower motor BLWM will operate at continuous blower airflow.

Component Self Test

Refer to page 68 for instructions.

Page 83

987MA

338307-2 Rev. C

A11429

Fig. 63 -- Wiring Diagram

Page 84

Casing Group

Blower door Bottom plate Control door Door knob assembly Top filler plate

Electrical Group

3--Amp fuse Circuit board Control box Door switch Junction box Limit switch(es) Transformer

987MA

Blower Group

Blower housing Blower motor Blower wheel Capacitor (when used) Capacitor strap (when used) Cut--off plate Power choke (where used)

Filter Group

Filter(s) Media Cabinet (when used)

PARTS REPLACEMENT INFORMATION GUIDE

Gas Control Group

Burner Flame sensor Gas valve Hot surface igniter Manifold Orifice

Heat Exchanger Group

Containment plate Coupling Box Heat exchanger assembly Primary HX cell panel Secondary HX assembly Tubing gaskets

Inducer Group

Collector box Condensate trap

Condensate trap elbow Gaskets Inducer Inducer assembly Inducer motor capacitor (when used) Inducer motor module (when used) Pressure switch(es)

TO OBTAIN INFORMATION ON PARTS: Consult your installing dealer or classified section of your local telephone directory under “Heating Equipment” or “Air Conditioning Contractors and Systems” headings for dealer listing by brand name or contact:

BRYANT HEATING & COOLING SYSTEMS

Consumer Relations Department

P.O. Box 4952

Syracuse, New York 13221--4952

1--800--428--4326

Have available the model number, series number, and serial number located on the unit rating plate to ensure correct replacement part.

Model Nomenclature

MODEL

987MA 42 060 V 17 A -- A

FIRE, EXPLOSION, ELECTRICAL SHOCK AND CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous operation, personal injury, death or property damage. Improper installation, adjustment, alteration, service, or maintenance can cause personal injury, property damage, or death. Consult a

qualified installer, service agency, or your local gas supplier for information or assistance. The qualified installer or service agency must use only factory--authorized replacement parts, kits, or accessories when modifying this product.

COOLING

CAPACITY

HEATING

CAPACITY

MOTOR WIDTH V OLTA GE

WARNING

FEATURES/

MINOR SERIES

E2011 Bryant Heating & Cooling Systems D 7310 W. Morris St. D Indianapolis, IN 46231 Printed in U.S.A. Edition Da te: 09/11

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Catalog No. II987MA--- 0 3

Replaces: II987MA---02