Thomas & Betts Reznor SCE Installation Operation & Maintenance

Download

Page 1

Model SCE

Separated-Combustion

Packaged Furnace/Blower

NOTE: Model SCE units are not certified for residential use.

INSTALLATION/OPERATION/MAINTENANCE

Form I-SCE (Version A)

Obsoletes Form RZ-NA I-SCE

TABLE OF CONTENTS Pages

Installation/Operation .............. 1-30

Check Installation & Startup 30-31

Optional Equipment ................ 32-33

Service/Maintenance ............... 33-36

INDEX by Page No.

Belts ......................................................... 24

Blower ...................................................... 24

Blower Rotation ....................................... 24

Adjusting Blower Speed .......................... 24

Burner Air Shutters .................................. 30

Burner Carryover Systems ........................ 29

Burner Orifices ... ........... .......... ................. 29

Burner Rack Removal .............................. 34

Burners ..................................................... 29

Check Installation & Startup ................... 30

Cleaning the Heat Exchanger ................... 35

Cleaning Pilot and Burners ..................... 34

Clearances .................................................. 4

Combustion Air .......................................... 7

Concentric Adapter Box ............................ 10

Optional Condensation Drain .................... 6

Optional Dampers & Controls .................. 32

Dimensions ................................................ 3

Dirty Filter Switch (Option) .................... 33

Drives ........................................................ 24

Duct Connections ...................................... 6

Ductstat (Optional) ................................... 25

Electrical Supply & Connections ............ 20

Optional Electronic Modulation .............. 26

Fan Control ............................................. 23

Filter Rack & Filters ................................ 32

Gas Piping and Pressures ......................... 18

Gas Valve ............................................ 24, 33

General ....................................................... 1

HAZARD INTENSITY LEVELS ............. 2

Horizontal Vent Terminal/

Combustion Air Inlet .......................... 12

Ignition System ....................................... 29

Installation Codes ...................................... 2

Limit Control .......................................... 23

Limit Control Check ............................... 35

MAINTENANCE .................................... 33

Manifold Pressure Setting ........................ 19

Motor ........................................................ 23

Mounting ................................................... 5

Optional Accessories ................................. 32

Pilot and Ignition Systems ...................... 29

SERVICE................................................. 33

Startup ..................................................... 30

Support ....................................................... 9

Suspension ................................................. 5

Thermostat ............................................... 20

Troubleshooting ...................................... 35

Optional Two-Stage Operation ................ 24

Uncrating ................................................... 3

Valve ........................................................ 24

Vent/Combustion Air System ............... 7, 33

Venting .................................................. 7-17

Vertical Vent Terminal/

Combustion Air Inlet .......................... 15

Warranty..................................................... 2

Wiring Diagram .................................. 21-22

REFERENCE

Replacement Parts ....................... Form P-SC

Gas Conversion .......................... Form P-GC

FOR YOUR SAFETY

If you smell gas:

1. Open windows.

2. Don't touch electrical switches.

3. Extinguish any open flame.

4. Immediately call your gas supplier.

FOR YOUR SAFETY

The use and storage of gasoline or other flammable vapors and liquids in open containers in the vicinity of this appliance is hazardous.

WARNING: Improper installation, adjustment, alteration, service, or maintenance can cause property damage, injury or death. Read the installation, operation, and maintenance instructions thoroughly before installing or servicing this equipment.

WARNING: Gas-fired appliances are not designed for use in hazardous atmospheres containing flammable vapors or combustible dust, in atmospheres containing chlorinated or halogenated hydrocarbons, or in applications with airborne silicone substances. See Hazard Levels, page

GENERAL

The instructions in this manual apply to Model SCE blower-type unit heater with blower cabinet.

Installation should be done by a qualified agency in accordance with the instructions in this manual and in compliance with all codes and requirements of authorities having jurisdiction.

Model SCE is design-certified by the Canadian Standards Association to ANSI Standards and approved to CSA Standards. Model SCE is available for use with either natural or propane gas. The type of gas, the firing rate, and the electrical characteristics are on the unit rating plate.

This separated combustion unit is designed and manufactured in accordance with the ANSI definition of separated combustion. That definition reads, "Separated Combustion System Appliance: A system consisting of an appliance and a vent cap(s) supplied by the manufacturer, and (1) combustion air connections between the appliance and the outside atmosphere, and (2) flue gas connections between the appliance and vent cap, of a type(s) specified by the manufacturer but supplied by the installer, constructed so that, when installed in accordance with the manufacturer's instructions, air for combustion is obtained from the outside atmosphere and flue gases are discharged to the outside atmosphere."

Separated combustion units are designed to separate air for combustion and flue products from the environment of the building in which the unit is installed. Separated combustion

Model Description

Separated-Combust ion, Blower-Ty pe

SCE

Unit Heater with Blower Cabinet

Front View

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 1

Rear View

Page 2

General (cont'd)

appliances are recommended for use in dust laden and some corrosive fume environments or in buildings with negative pressure (up to .15" w.c.). As the definition states, all separated combustion, power-vented equipment must be equipped with both combustion air and exhaust piping to the outdoors.

Definitions of Hazard Levels in this Manual

1. Installation Codes

Special Installations (Aircraft Hangars/ Garages)

HAZARD INTENSITY LEVELS

1. DANGER: Failure to comply will result in severe personal injury or death and/or property damage.

2. WARNING: Failure to comply could result in severe personal injury or death and/or property damage.

3. CAUTION: Failure to comply could result in minor personal injury and/or property damage.

These units must be installed in accordance with local building codes. In the absence of local codes, in the United States, the unit must be installed in accordance with the National Fuel Gas Code NFPA 54/ANSI Z223.1 (latest edition). A Canadian installation must be in accordance with the CSA B149. Natural Gas and Propane Installation Codes. Both codes are available from CSA Information Services, 1-800-463-6727. Local authorities having jurisdiction should be consulted before installation is made to verify local codes and installation procedure requirements.

Installations in aircraft hangars should be in accordance with NFPA No. 409 (latest edition), Standard for Aircraft Hangars; in public garages in accordance with NFPA No. 88A (latest edition), Standard for Parking Structures; and for repair garages in accordance with NFPA No. 88B (latest edition), Standard for Repair Garages. In Canada, installations in aircraft hangars should be in accordance with the requirements of the enforcing authorities, and in public garages in accordance with CSA B149 codes.

All Installations

2. Warranty

These gas-fired products are certified by ANSI Z83 family of standards governing the safe usage of heating equipment in the industrial/commercial marketplace. This includes using the heaters in makeup air applications to supply corridor pressurization in commercial buildings such as office structures and apartment complexes.

The heaters are not certified as residential heating equipment and should not be used as such.

Clearances from the heater and vent to combustible construction or material in storage must conform with the National Fuel Gas Code ANSI Z223.1a (latest edition) pertaining to gasburning devices, and such material must not attain a temperature over 160°F by continued operation of the heater.

Refer to the limited warranty information on the Warranty Card in the "Owner's Envelope".

Warranty is void if ...

a. Separated-combustion heaters are used in atmospheres containing flammable vapors or

atmospheres containing chlorinated or halogenated hydrocarbons or any contaminant (silicone, aluminum oxide, etc.) that adheres to the spark ignition flame sensing probe.

b. Wiring is not in accordance with the diagram furnished with the heater. c. Unit is installed without proper clearance to combustible materials.

Form RZ-NA I-SCE, Page 2

Page 3

3. Dimensions

FIGURE 1 - Model SCE Dimensions - inches ±1/8 (mm ±3)

Standard Model SCE

Model SCE with Optional Horizontal Inlet with Duct Flanges

Size

Dim

ensions (inches ±1/8)

125 150, 175 200, 225

250

300

350

400

Dimensions (mm±3)

125 150, 175 200, 225

250

300

350

400

A BDE FGHJKLMN

32-1/4 25-1/4 15-1/ 4 8-1/8 16-1/4 7 17-3/4 17-3/8 17 1/2 40-1/ 4 27-3/ 4 32-1/4 30-3/4 20-3/ 4 8-1/8 21-3/4 7 23-1/4 22-7/8 18-3/8 1/2 39 27-3/4 35-1/4 36-1/4 26-1/ 4 10-3/ 4 27-1/ 4 10 28-3/4 28-3/8 17 1/2 40-1/4 30-3/4 35-1/4 43-1/2 33-1/ 2 9-3/4 34-1/2 9 36 35-5/ 8 16 1/2 39-1/4 30-3/4 35-1/4 44-1/2 4-1/5 10-3/4 35-1/2 10 37 38-5/8 17 3/4 40-1/ 4 30-3/ 4 35-1/4 50 40 10-3/4 41 10 42-1/2 42-1/8 18-3/ 8 3/ 4 39 30-3/4 35-1/4 55-1/2 45-1/ 2 10-3/ 4 46-1/ 2 10 48 47-5/ 8 17 3/ 4 40-1/4 30-3/4

819 641 387 206 413 178 451 441 432 13 1022 705 819 781 527 206 552 178 591 581 467 13 991 705 895 921 667 273 692 254 730 721 432 13 1022 781 895 1105 851 248 876 229 914 905 406 13 997 781 895 1130 876 273 902 254 940 930 432 19 1022 781 895 1270 1016 273 1041 254 1080 1070 467 19 991 781 895 1410 1156 273 1181 254 1219 1210 432 19 1022 781

2

51mm

18

457mm

7-7/32 183mm

6-31/32 177mm

19-1/2 495mm

2-1/4 57mm

6-3/32 155mm

3/4

19mm

3/4 19mm

Combustion Products Discharge 6 (150mm) O.D.

Connections

19-1/2 495mm

34 (864mm) 24-1/8 (613mm)

2-13/16 71mm

3-5/16 84mm

Electrical

4-5/16 110mm

10

254mm

1-1/8 29mm

58-1/8 (1,476mm)

59-1/16 (1,500mm)

3/4 19mm

Combustion Products

3/4

Discharge 6 (150mm) O.D.

19mm

34 (864mm) 24-1/8 (613mm)

L (Gas

Connection)

Electrical

Connections

7-1/2

191mm

1-1/2 38mm

7-1/2 191mm

4-5/16 110mm

10 254mm

1-1/8 29mm

58-1/8 (1,476mm)

59-1/16 (1,500mm)

4-9/16 116mm

Combustion Air Inlet 6 (150mm) I.D.

2-1/4 57mm

2-3/4 70mm

15/16 24mm

1-1/2 38mm

(4) Mounting Sockets 1 IPS free turning female pipe thread

19-1/2 495mm

4-9/16 116mm

2-3/4 70mm

L (Gas Connection)

15/16 24mm

3-1/4 83mm

(4) Mounting Sockets, 1 IPS free turning female pipe thread

2-1/4 57mm

4. Uncrating

The furnace is shipped completely assembled. Immediately upon uncrating, check the gas specifications and electrical characteristics of the unit to be sure that they agree with the gas and electric supply at the installation site. Check the unit for any damage that may have been incurred during shipment. If damage is found, document the damage with the transporting agency and immediately contact your Reznor distributor. If you are an authorized Distributor, follow the FOB freight policy procedures as published by Thomas & Betts for Reznor products. The bottom corners are fastened to the crate with angle clips. Remove the lag screws from the shipping clips. Remove the clips and return the bolts to the heater legs to support the corner leg and the heater bottom. Putting the bolts back in the heater is required.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 3

Page 4

4. Uncrating (cont'd)

To protect the unit during shipping, blower models have special supports that must be removed before installation. Follow these instructions to remove:

Blower Support Legs - Remove the blower support legs and screws. Motor Shipping Block - Remove the wooden block located under the motor bracket. Find

the two rubber pads shipped in the instruction envelope. Place these pads on the ends of the motor bracket bolts.

Motor Shipping Plate - Units that are equipped with motors of

1-1/2 HP or less have a metal shipping plate attached between the motor and the blower housing. The shipping plate must be removed and the plate and screws discarded. On units factory equipped with an optional belt guard, the belt guard must be removed to reach the shipping plate.

Vent Terminal/Combustion Air Inlet Kit with Concentric Adapter Box -

Required for All Installations

Options

Some gas control options have parts either shipped loose with the heater or shipped separately. If your unit is equipped with any of the gas control options in the table, be sure these parts are available at the job site.

Before beginning installation, be sure that all other shipped-separate options ordered are available at the site, also. Shipped-separate options could include a shutoff valve, a condensate drain kit, a thermostat, a remote console, a disconnect switch, or high temperature vent sealing tape.

5. Clearances and Location

For safety and convenience, provide clearances as shown in the following table. Clearance to combustibles is defined as the minimum distance from the heater to a surface or object that is necessary to ensure that a surface temperature of 90°F above the surrounding ambient temperature is not exceeded. Minimum clearances are also listed on the heater rating plate.

The concentric adapter assembly in the venting/combustion air kit (Option CC2 or CC6) is required on all separated combustion models. Be sure that the concentric adapter carton is at the installation site. (See parts lists in Paragraph 9.)

Application Option S hipped S eparate Components Heati ng -- Gas Control Option

Makeup Air -- Gas Control Options AG9

AG7

AG3

AG15

AG16

AG39

Thermostat, P/N 48033

Control Switch, P/N 29054 Remot e Temperature Selector, P/N 48042 Control Switch, P/N 29054 Remot e Temperature Selector, P/N 115848 Stage Adder Module, P/N 115849 Control Switch, P/N 29054 Remot e Temperature Selector, P/N 115848 Stage Adder Module, P/N 115849 Remote Disp lay M odule, P/N 115852 Control Switch, P/N 29054 Remot e Temperature Selector, P/N 174849

Minimum Clearances

- inches (mm)

Location

Form RZ-NA I-SCE, Page 4

Top

(152mm)

For best results, the heater should be placed with certain rules in mind. In general, a unit should be located from 8 to 12 ft (2.6 to 3.6M) above the floor. Units should always be arranged to blow toward or along exposed wall surfaces, if possible. Where two or more units are installed in the same room, a general scheme of air circulation should be maintained. Suspended heaters are most effective when located as close to the working zone as possible, and this fact should be kept in mind when determining the mounting heights to be used. However, avoid directing the discharged air directly on the room occupants. Partitions, columns, counters, or other obstructions should be taken into consideration when locating the unit heater so that a minimum quantity of airflow will be deflected by such obstacles. When units are located in the center of the space to be heated, the air should be discharged toward the exposed walls. In large areas, units should be located to discharge air along exposed walls with extra units provided to discharge air in toward the center of the area. At those points where infiltration of cold air is excessive, such as at entrance doors and shipping doors, it is desirable to locate the unit so that it will discharge directly toward the source of cold

air from a distance of 15 to 20 feet (4.5 to 6 M).

Control Side Side Opposite Controls To Combus tibles To Non-Combustibles

6" (152mm) plus

width of unit

6" (152mm) 6" (152mm) 0" (0mm)

BottomSides

CAUTION: Do not locate the heater where it may be exposed to water spray, rain, or dripping water.

Page 5

6. Suspension and Mounting

Weights

Before installing, check the supporting structure to be sure that it has sufficient load-carrying capacity to support the weight.

Net Weight (lbs and kg)

Size 125 150-175 200-225 250-300 350 400

lbs 313 358 382 482 498 560

kg 142 162 173 219 226 254

Suspension

WARNING: Units must be supported level for proper operation. Do not place or add additional weight to the suspended unit. See Hazard

Levels, page 2.

FIGURE 2 - Suspension Methods

Mounting Supports

FIGURE 3 - Model SCE Support Locations

FIGURE 4 - Corner Mounting Supports (NOTE: Support is also required where furnace and blower cabinets meet. See FIGURE 3.)

Model SCE has four-point suspension. See hanger centerline dimensions in FIGURE 1, Paragraph 3. At each suspension point, the unit is factory-equipped with a free-turning, female, 1" NPT pipe hanger. Suspend by connecting the pipe hanger to a 1" threaded pipe. See suspension method on the left in FIGURE 2. As an alternative method, the factory-installed pipe hanger

may be removed and the heater suspended as illustrated on the right in FIGURE 2.

Standard Assembly

1 Pipe Flange

1 Pipe

Threaded

Socket

Installer Replaced Assembly

Washer Nut Assembly

Washer Nut

Assembly

Heater Top

3/8 Rod

(Standard threaded socket assembly is removed.)

Access through the side panel

Model SCE requires six support locations. See FIGURE 3. Supports available from the manufacturer (P/N 74487) or field-fabricated legs as illustrated in FIGURE 4 may be used at the four corner support locations. Do not use this type of support at the center support locations (between the furnace and the blower section). At the center locations, a field-fabricated, angle-iron brace support must extend horizontally, jointly supporting a portion of both the furnace and the blower cabinet. All supports must be noncombustible.

Field-supplied supports between the blower cabinet and the furnace

Airflow

must extend horizontally supporting both sections.

Blower Section

Furnace Section

Support Locations

Furnace

Shipping Bolt Lug

Access Panel

Retaining Screw

P/N 74487 (4 required)

• above - available as a part

• right - field fabricated

6

(152mm)

2 x 2 x 1/4

Angle Iron Leg

6 x 6 x 1/4

Metal Plate

Cabinet Leg

1/4 x 1-1/2

Hex Head

Bolts

Spacers

4 (102mm)

2-1/4 (57mm)

A = 6 (152mm) minimum height for

clearance to combustibles. The recommended height is 8 (203mm) for plumbing and service

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 5

Drill 9/32 clearance holes in angle iron leg and cabinet leg

7

(178mm)

1/4 Nuts

Lockwashers

Angle Iron Leg

Page 6

7. Optional Condensation Drain for Duct Furnaces

Model SCE furnaces are certified for installation upstream or downstream from a cooling coil. When installed downstream from a refrigeration system, condensation will form; and therefore, adequate provision must be made to dispose of condensate. Periodic cleaning of the condensate collection and disposal system is required. Install drain connection, Option CS1, on the furnace casing as illustrated in FIGURE 5.

FIGURE 5 - Option CS1, P/N 31765, Optional Condensate Drain Connection

8. Duct Connections

FIGURE 6 - Duct Connection Dimensions inches (mm)

Bottom of the Furnace Casing

#10 x 1-1/4 Bolt and Nut

3/4 Pipe Waste Nut

Terminate drain outside of the building. Provide a trap to prevent air from entering the combustion zone. Periodic cleaning of the condensate collection and disposal system is required. NOTE: Requires a four-inch (102mm) minimum clearance under the furnace if a 90° street elbow is used.

(457)

3/4 (19)

3/4

(19)

Gasket

Size G

125 15-1/4" (387mm)

150, 175 20-3/4" (527mm)

200, 225 26-1/4" (667mm)

250, 300 34-1/2" (876mm)

350 40" (1016mm)

400 45-1/2" (1156mm)

Requirements and Suggestions for Connecting and Installing Ducts

• Type of Ductwork - The type of duct installation to be used depends in part on the type of construction of the roof (whether

wood joist, steelbar joist, steel truss, pre-cast concrete) and the ceiling (whether hung, flush, etc.).

• Ductwork Material - Rectangular duct should be constructed of not lighter than No. 26 U.S. gauge galvanized iron or No. 24 B

& S gauge aluminum.

• Ductwork Structure - All duct sections 24 inches (610mm) or wider, and over 48 inches (1219mm) in length, should be cross

broken on top and bottom and should have standing seams or angle-iron braces. Joints should be S and drive strip, or locked.

• Through Masonry Walls - No warm air duct should come in contact with masonry walls. Insulate around all air duct through

masonry walls with not less than 1/2" (1" is recommended) of insulation.

• Through Unheated Space - Insulate all exposed warm air ducts passing through an unheated space with at least 1/2" (1" is

recommended) of insulation.

• Duct Supports - Suspend all ducts securely from adjacent buildings members. Do not support ducts from unit duct connections.

• Duct Sizing - Proper sizing of the supply air ductwork is necessary to ensure a satisfactory heating installation. The recognized

authority for such information is the Air Conditioning Contractors Association, 2800 Shirlington Road, Suite 300, Arlington, VA 22206 (www.acca.org). A manual covering duct sizing in detail may be purchased directly from them.

CAUTION: An external duct system static pressure not within the limits shown on the rating plate, or improper motor pulley or belt adjustment, may overload the motor. See Hazard Levels, page 2.

• Removable Panels - The ducts should have removable access panels on both upstream and downstream sides of the furnace.

These openings must be accessible when the furnace is in service and should be a minimum of 6" x 10" (152mm x 254mm) in size so smoke or reflected light may be observed inside the casing to indicate the presence of leaks in the heat exchanger. The covers for the openings must be attached in such a manner as to prevent leakage. See FIGURE 7A.

• Horizontal Discharge Duct Length - A minimum horizontal duct run of 24" (610mm) is recommended before turns or branches

are made in the duct system to reduce losses at the furnace outlet.

• Supply Air Duct/Furnace Horizontal Connection - The seal between the furnace and the duct must be mechanical. Duct

connection should be made with "U" type flanges on the top and bottom of the connecting duct. Slide the duct over the flanges of the heater giving an airtight fit. Provide "U" type channels for the side flanges to ensure tight joints. Use sheetmetal screws

to fasten ducts and "U" channels to the furnace flange. See FIGURE 7B.

Form RZ-NA I-SCE, Page 6

Page 7

CAUTION: Joint where supply air duct attaches to the furnace must be sealed securely to prevent air leakage into drafthood or burner rack area. Leakage can cause poor combustion, pilot problems, shorten heat exchanger life, and cause poor performance. See Hazard levels, page 2.

• Return Air Duct/Furnace Connection - All return air ducts should be attached and

sealed to return air flanges to provide airtight connection.

• Return Air Duct/Grill Size - Make certain that return air ducting or grills have a free

area equal to the return duct size connection.

FIGURE 7A - Connecting Ductwork to the Furnace

(1) Flanges on the furnace (heat exchanger) turn out as shown. (2) Shape duct connection as shown -- "U" on top and bottom; "L" on sides. (3) Slide "U" channels over furnace top and bottom flanges making connection. (4) Form "U" channels to seal sides. Drill and lock with

sheetmetal screws.

FIGURE 7B - Install "U" Channel on Sides of Duct Connection

Furnace

Heater

9. Venting and Combustion Air

WARNING: Do not use an existing venting system.

This heater requires

installation of the combustion air/vent system ordered with the unit (either Option CC2 or Option CC6).

6

Duct

U Channel

All separated combustion, power vented units MUST BE equipped with both combustion air and exhaust piping to the outdoors. The unique concentric adapter box designed for use with this heater allows for both combustion air and exhaust piping with only one horizontal or vertical penetration hole in the building.

These instructions apply to installation and use of the concentric adapter and vent/combustion air kit (Option CC2 or CC6) designed for use with all Reznor separated-combustion products. The systems illustrated in this manual are the only venting/combustion air systems approved for these separated combustion units. Do not use this concentric adapter box with any other products.

Installation should be done by a qualified agency in accordance with these instructions. The qualified service agency installing this separated-combustion system is responsible for the installation.

Hazards of Chlorine - The presence of chlorine vapors in the combustion air of gas-fired heating equipment presents a potential corrosion hazard. Chlorine found usually in the form of freon or degreaser vapors, when exposed to flame, will precipitate from the compound, and go into solution with any condensation that is present in the heat exchanger or associated parts. The result is hydrochloric acid which readily attacks all metals including 300 grade stainless steel. Care should be taken to separate these vapors from the combustion process. This may be done by wise location of unit vent terminal and combustion air inlet with regard to exhausters or prevailing wind directions. Remember, chlorine is heavier than air. This fact should be kept in mind when determining installation location of these heaters and building exhaust systems.

Access Panel

(152mm)

Duct

10 (254mm)

in Duct

U Channel of Light Gauge Metal

WARNING: SC Series separated combustion units are not designed or approved for use in atmospheres containing flammable vapors or atmospheres highly laden with chlorinated vapors. See Hazard Levels, page 2.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 7

Page 8

9. Venting and Combustion Air (cont'd)

1) Type of Pipe

Vent Pipe

Specific Venting Requirements

All pipe is field supplied. Requirements are listed for both the vent pipe and the combustion air inlet pipe.

• Vent pipe approved for a Category III appliance OR single-wall, 26-gauge or heavier galvanized (or a material of equivalent durability and corrosion resistance) vent pipe is

required between the heater and the concentric adapter box.

• Double-wall (Type B) vent pipe is required for vent terminal section. The length of vent pipe that extends through the box and runs concentric through the combustion air pipe must be one-piece with no joints.

Combustion Air Pipe

2) Venter Outlet and Combustion Air Inlet

• NOTE: If using 7" pipe on Sizes 200-400 (see table below), use a taper-type 6" to 7" enlarger to attach the vent pipe and a 7" to 6" reducer to attach the combustion air pipe.

3) Pipe Length

and Diameter

Pipe Diameter and Maximum Pipe Length Between the Heater and the Concentric Adapter Box

• Minimum length between the

heater and the concentric adapter box is 5 feet (1.5M).

Diameters of Outdoor Concentric Pipes

Model SCE - All Sizes Inl et Ai r Pi pe Diameter

Vent Pipe Diame ter

203mm

127mm

• Sealed, single-wall galvanized pipe is recommended for combustion air.

Model SCE heaters have both an inlet air and a venter outlet connection. Both are 6" diameter for all sizes.

Taper-type Enlarger

Airflow

Taper-type Reducer

Airflow

Pipe diameter and length requirements listed for the indoor sections of pipe (between the heater and the concentric adapter box) are in the table below. Vent pipe diameters and maximum indoor vent lengths apply to both horizontal and vertical vents. Add all straight sections and equivalent lengths for elbows. The total length of the straight sections and

elbows must not exceed the Maximum Length.

Pipe Diameter and Maximum Pipe Length from Heater to Conc entr ic Adapter

Pipe Diameter

SCE

125 150 175

200

225

250

300

350

400

The diameters of the outside (terminal) concentric pipes are shown in the concentric box connection illustrations in FIGURE 11, page 11. The outdoor lengths depend on the instal- lation. Outdoor vent length requirements are listed in the installation instructions for the horizontal and vertical vent/combustion air kits on pages 12-17.

Vent Pipe Inlet Air Pipe

inches mm inches mm feet M feet M feet M

6 152 6 152 50 15 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2 6 152 6 152 50 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2 6 152 6 152 30 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2 6 152 6 152 30 15 8 2.4 4 1.2 7 178 7 178 70 21 8 2.4 4 1.2

Venter Outlet Connection (diameter) SCE 125 150 175 200 225 250 300 350 400

inches666666666

mm 152 152 152 152 152 152 152 152 152

Combus tion Air Inlet Connection (diameter) SCE 125 150 175 200 225 250 300 350 400

inches666666666

mm 152 152 152 152 152 152 152 152 152

Maxi mum

Length 90° Elbow

Equivalent Straight Length for a

45° Elbow

4) Joints and Sealing

Form RZ-NA I-SCE, Page 8

Provide pipes as specified in Requirement No. 1 and seal joints as follows:

• If using Category III

joining and sealing Category III vent pipe sections.

• If using single-wall vent pipe run, secure slip-fit pipe connections using sheetmetal screws or rivets. Seal all joints with aluminum tape or silicone sealant.

vent pipe run, follow the pipe manufacturer’s instructions for

Page 9

FIGURE 8 - Follow STEPS to join Double-Wall (Type B) Pipe and

the Vent Terminal

Cap (horizontal or vertical)

(NOTE: Pipes and vent caps may not look exactly as shown in the illustrations. Instructions apply to both horizontal and vertical vent kits.)

• To seal joints in the single-wall combustion air pipe, secure slip fit pipe connections using sheetmetal screws or rivets. Seal all joints with aluminum tape or silicone sealant.

• To seal joint in the terminal section of double-wall vent pipe (allowed ONLY ABOVE

the concentric pipes on a VERTICAL vent, follow the pipe manufacturer’s instructions

for joining and sealing double-wall vent pipe sections.

• When joining the terminal section of illustrated step-by-step instructions in FIGURE 8. When joining the terminal section of double-wall vent pipe to a single-wall or Category III vent pipe run, follow the illustrated step-by-step instructions in FIGURE 9.

Figure 8 -

Place a continual 3/8” bead of silicone sealant around the circumference of the vent cap collar. This will prevent any water inside the vent cap from running down the double-wall pipe.

Do STEP 2 immediately following STEP 1.

STEP 1

Figure 8 - STEP 2

Insert the collar on the vent cap inside the inner wall of the double-wall pipe. Insert as far as possible. Add additional silicone sealant to fully close any gaps between the vent cap and the double wall pipe. This is necessary to prevent water from entering the double wall pipe.

double-wall vent pipe to the vent cap, follow the

FIGURE 9 - Follow STEPS to join the Double-Wall (Type B) Pipe to the Taper-type Reducer that Joins it to the Single-Wall or Category III Vent Run

Figure 9 -

On the taper-type reducer, place a continual 1/4” bead of silicone sealant around the circumference.

STEP 1

Do STEP 2 immediately following STEP 1.

5) Support

NOTE: The double-wall vent terminal pipe does not attach to the concentric adapter box and must be

supported during installation.

Figure 8 - STEP 3

Secure the vent cap to the double-wall pipe by drilling and inserting a 3/4” long sheetmetal screw into the vent cap collar. Do not overtighten screw.

Make this connection a maximum of 6" (152mm) from the concentric adapter box.

Figure 9 - STEP 2

Insert the collar of the reducer into the inner pipe of the double-wall pipe until the bead of sealant contacts the inner pipe creating a sealed joint.

5" I.D.

Double-

Wall

Pipe

6" to 5" or

7" to 5"

Taper-

Type

Figure 9 - STEP 3

Spaced equally around the double-wall pipe, drill three small holes below the sealant ring. Insert 3/4 inch long sheetmetal screws to secure the joint. Do not overtighten screws.

Reducer

Support horizontal runs every six feet (1.8M). Support vertical runs of type "B" double-wall or Category III vent pipe in accordance with the requirements of the pipe manufacturer. Support single-wall vertical pipe in accordance with accepted industry practices. Do not rely on the heater or the adapter box for support of either horizontal or vertical pipes. Use noncombustible supports on vent pipe.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 9

Page 10

9. Venting and Combustion Air (cont'd)

Specific Venting Requirements (cont'd)

6) Clearance

7) Concentric Adapter Box

Do not enclose the vent pipe or place pipe closer than 6" (152mm) to combustible material.

All separated combustion installations require a concentric adapter box as illustrated in FIGURE 10. The concentric adapter box is included in the vent/combustion air kit. Installation instructions depend on whether the vent system is horizontal (Option CC6) or vertical (Option CC2).

FIGURE 10 - A Concentric Adapter Box is a Required Part of all Model SCE Installations

View of Heater Connection Side

Collar for connecting indoor portion of the combustion air pipe

Opening for double-wall vent pipe to pass through the box.

P/N 205885, Concentric Adapter Box

2 (51mm)

6-1/32

(153mm)

2 (51mm)

Top View

Heater Side View

6 Collar for Combustion Air Pipe

8 dia Collar for Combustion Air Pipe

View of Vent Terminal Connection Side

Collar for attaching outside concentric portion of the combustion air pipe

Concentric Adapter Box Airflow

Vent (exhaust gas) flows through field-supplied double-wall pipe that extends straight through the concentric adapter box.

14-1/4

(362mm)

End View

showing

Airflow

5

(127mm)

5-7/32

(133mm)

5-21/32

(144mm)

5-9/32

(134mm)

13-3/8 (340mm)

diameter

4

(102mm)

Opening for vent pipe to pass through the box

Gray Arrows show Flow of Combustion Air

Form RZ-NA I-SCE, Page 10

Page 11

Pipe Connections at the Concentric Adapter Box

FIGURE 11 - Concentric Adapter Box Connections

When pipe diameters differ, depending on direction of airflow, join the pipes with either a tapertype reducer or enlarger. Refer to illustrations in FIGURE 11 for pipe connection requirements at the concentric adapter box.

Do NOT make actual connections until after reading the instructions and length requirements for installing the vent/combustion air kit. The connection requirements are the same for both verti-

cal and horizontal systems, but the length of the double-wall pipe will vary.

Model SCE 125-400 - Pipe diameters and connections required at the concentric adapter box when using 6 pipes between the furnace and the box

• If using 6” diameter pipes, Model SCE always require a 6” to 5” (152 to 127 mm) reducer in the vent pipe.

Taper-type

Airflow

Reducer

• If using 7” diameter pipes (allowed on Sizes 200-400),

Model SCE always requires a 7” to 5” (178 to 127 mm) reducer in the vent pipe and a 6” to 7” (152 to 178 mm) enlarger for attaching the combustion air pipe.

Taper-type

Airflow

Reducer

Taper-type Enlarger

Requires a 6 to 5 inch (152 to 127mm) taper-type reducer a maximum of 6 (152mm) from the concentric adapter box.

6 (152mm) diameter single-wall or Category III vent pipe attaches to the heater

6 (152mm) diameter single-wall inlet air pipe attaches to the heater

5 (127mm)

inside diameter

double-wall

vent pipe

Top View of Concentric Adapter

Box showing Pipe Connections

8 (203mm)

diameter

single-wall

inlet air pipe

Model SCE 200-400 - Pipe diameters and connections required at the concentric adapter box when using 7 pipes between the furnace and the box

5 (127mm)

inside diameter

double-wall

vent pipe

Top View of Concentric Adapter

Box showing Pipe Connections

8 (203mm)

diameter

single-wall

inlet air pipe

Requires a 7 to 5 inch (178 to 127mm) taper-type reducer a maximum of 6 (152mm) from the concentric adapter box.

7 (178mm) diameter single-wall or Category III vent pipe attaches to the heater

7 (178mm) diameter single-wall inlet air pipe attaches tot he heater

Requires a 6 to 7 inch (152 to 178mm) taper-type enlarger at the concentric adapter box.

HORIZONTAL OR VERTICAL?

Is the Separated Combustion Vent/ Combustion Air System Horizontal or Vertical?

Horizontal, Option CC6,

instructions begin on page 12.

Vertical, Option CC2,

instructions begin on page 15.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 11

Page 12

HORIZONTAL VENT INSTRUCTIONS

Components Required Factory and Field

Parts in the Horizontal Vent Terminal/Combustion Air Package (Option CC6)

Qty P/N Des cription

1 205883 Comp let e Ho rizont al Ven t Kit (Sa me as Opt ion CC6)

1 205885 Concentric Ad ap ter Box A ssembly (See 1 53316 Screened Exhaust Assembly (illustrated below) 1 205894 Inlet Guard (illustrated below) 4 37661 #10-16 x 1/2" long Sc rews to attach th e in let gu ard 2 207232 Brackets for attaching Concentric Adapter Box (See 1 53335 Tube of High Temperature (450°F) Silicone Sealant

FIGURE 10

Screened Exhaust Assembly,

Inlet Guard, P/N 205894

P/N 53316

, page 10.)

FIGURE 12,

page 13.)

Field-supplied installation requirements:

Installation Instructions for Horizontal Vent Kit Option CC6

Clearances to Horizontal Vent Terminal

WARNING: All vent terminals must be positioned or located away from fresh air intakes, doors and windows to preclude combustion products from entering occupied space. Failure to comply could result in severe personal injury or death and/or property damage.

Form RZ-NA I-SCE, Page 12

• Vent pipes - see requirements, page 8.

• Combustion air pipes - see requirements, page 8.

• Taper-type vent pipe diameter reducers and/or increasers as required.

• Thimble (a thimble is not required if wall is of non-combustible construction).

• Flashing.

• Sheetmetal screws, tape, and sealant as required.

1. Determine the location on the outside wall for the vent terminal. Location must comply with vent length requirements, Requirement No. 3 on page 8. In most applications, the terminal would be on a level with the heater mounting height. Allow 1/4" per foot (6mm per 305mm) downward pitch for condensate drain.

The distance of the termination of the horizontal vent from adjacent public walkways, adjacent buildings, openable windows, and building openings must be in accordance with local codes or, in the absence of local codes, must conform with National Fuel Gas Code Z223.2. Local codes supersede all provisions in these instructions and in the National Fuel Gas Code. Minimum clearances for the horizontal vent terminal are shown below. Also, select a location that complies with adjoining building clearances as shown in FIGURE 13, page 14.

Products of combustion can cause discoloring of some building finishes and deterioration of masonry materials. Applying a clear silicone sealant that is normally used to protect concrete driveways can protect masonry materials. If discoloration is an esthetic problem re-locate the vent or install a vertical vent.

Structure

Forced air inlet with in 10 ft (3.1M)* 3 ft (0.9M ) above Combustion air inlet of another appliance 6 ft (1.8M) Door, window, or gravity air inlet (any building opening)

Electric meter, gas meter ** an d relief equipment Gas regu lato r ** U.S. - 3 ft (0.9M); Cana da - 6 ft (1.8M) horizo ntally) Adjoining building or parapet 6 ft (1.8M) Adjacent public walkways 7 ft (2.1M) above Grade (gro un d level) 3 ft (.9M ) ab ov e***

*Does not apply to the inlet of a direct vent appliance. **Do not terminate the vent directly above a gas meter or service regulator. *** Consider local snow depth conditions. The vent must be at least 6” (152mm) higher than anticipated snow depth.

2. Install the Vent Pipe and Combustion Air Pipe Runs - Use the type of pipe specified in Requirement No. 1, page 8. Comply with requirements in Requirement No. 2 and No. 4, page 8, when attaching pipes to the heater.

Seal all joints. Due to the high temperature, do not enclose the exhaust pipe or place pipe closer than 6" (152 mm) to combustible material. Extend the runs close to the wall location selected in Step 1. Support pipes as required in Requirement No. 5, page 10.

Minimum Cle arance s for Ve nt Terminal Location (all dire ctio ns unless s pecified)

4 ft (1.2M ) ho rizontally 4 ft (1.2M ) below 1 ft (305mm) above U.S. - 4 ft (1.2M) horizon tally ; Can ad a - 6 ft (1.8M)

Page 13

HORIZONTAL VENT INSTRUCTIONS (cont’d)

3. Prepare a hole through the outside wall for the 8" (203mm) diameter combustion air pipe. Outside wall construction thickness should be between 1" (25mm) minimum and 48"

(1143mm) maximum. The larger diameter combustion air pipe serves as clearance for the vent pipe on non-combustible construction. A thimble may be required depending on wall construction and/or local codes.

4. Prepare the Concentric Adapter Box a) Attach the brackets to the box. Follow the instructions in FIGURE 12.

FIGURE 12 - Brackets for Attaching the Concentric Adapter Box to the Wall

2) Attach the Box to the Wall (Step 5)

When the box is attached to the wall in Step 5, use the 2-1/2 (64mm) portion of the brackets.

To adjust to construction each bracket has

three 7/32 diameter holes.

1) Attach the Brackets to the Box - The 6 (152mm) portion of each bracket is designed with five 7/32 diameter holes so that attach ment to the box can be adjusted.

If the wall is combustible, position brackets to allow for a 2 (51mm) clearance between the box and the

wall. Adjust bracket attachment to allow for the slight

downward pitch of the terminal vent pipe. After careful positioning, use sheetmetal screws to attach the brackets. NOTE: If any holes are made in the box in error, they must be sealed.

b) Attach the outside portion of the combustion air pipe to the box. Determine the length by measuring the bracket length from box to wall, plus the wall thickness, plus 2" (51 mm). (The inlet air pipe should extend beyond the outside wall approximately 2" (51mm).)

Attach the inlet air pipe to the collar of the concentric adapter with sheetmetal screws and seal.

5. Attach the concentric adapter box to the wall. Insert the combustion air pipe through the wall. Attach the brackets (FIGURE 12) to the wall. On the outside, caulk or flash the inlet air pipe. Flashing is field-supplied.

6. Position the inlet guard over the end of the combustion air pipe. See FIGURE 13, page

14. Attach the guard to the inlet air pipe with the four 1/2" long screws provided.

7. Determine length and install the double-wall terminal vent pipe.

a) Determine length of pipe. The length of the vent pipe is determined by the installation

within the maximum and minimum requirements. The vent pipe extending through the box and the inlet air pipe must be one piece of double-wall vent pipe without joints. See FIGURE 13, to determine lengths of each segment and calculate the total length required. The transition to the single-wall or Category III vent pipe run, must be made a maximum of 6” (152mm) from the heater side of the box.

b) Install double-wall terminal vent pipe. Being sure the vent pipe is in the proper flow direction, slide the end through the box. Position the vent pipe so that it will extend between 16" (406mm) and 24” (610mm) past the end of the combustion air pipe and no more than 6” (152mm) out of the box toward the heater.

Use a taper-type reducer to attach the 5" double-wall vent pipe to the 6" or 7" single-wall or Category III vent pipe run. Follow the instructions in FIGURE 9 , page 9.

8. Attach the exhaust (vent) cap to the end of the vent pipe. Align the cap so that its baffle strips are positioned on the horizontal and vertical centerlines (See FIGURE 13). Follow the instructions in FIGURE 8, page 9, to attach the exhaust cap. (NOTE: If vent pipe is inserted from outside, cap may be attached before the double-wall vent pipe is installed. If cap is attached first, be sure the baffle strips are positioned correctly when attaching the vent terminal pipe to the vent run.)

9. Seal the vent pipe. Verify that the double-wall section of vent pipe has a slight downward drop (1/4” per foot/6mm per 305mm) toward the vent terminal end. Use silicone sealant and seal the circumference of the pipe and the opening of the box. Seal the area around the pipe

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 13

Page 14

HORIZONTAL VENT INSTRUCTIONS (cont’d)

FIGURE 13 - Installation of a Typical SeparatedCombustion Unit with Horizontal Vent and Combustion Air Pipes (Option CC6)

completely.

10. Attach the indoor combustion air pipe. If using 6" pipes, attach the single-wall combustion air pipe run to the collar on the concentric adapter box with sheetmetal screws. If using 7” pipe on Sizes 200-400, install a taper type enlarger as illustrated In FIGURE 11, page 11.

Seal joints with tape or sealant.

Installation of the horizontal vent and combustion air system on your separated-combustion unit is complete. Verify compliance with all venting installation requirements, pages

8-11, and FIGURE 13.

One piece of

Double-Wall

Vent Pipe

Screened

Exhaust

Cap

Top View

2 (51mm)

Inlet Air

Guard

16 (406mm)

minimum

24 (610mm)

maximum

Wall

1 (25mm)

minimum

48 (1219mm) maximum

Building Overhang

2 (51mm) if wall is combustible Attach box to wall with brackets.

Combustion Air to heater (seal joints)

Vent (Flue Exhaust) Pipe

from heater (seal joints)

Attach double-vent pipe to vent run no

6

(152

mm)

more than 6 (152mm) from the box. A taper-type reducer is required.

Distance between the

Concentric Adapter Box

Box

and the Heater

For Maximum Length,

Adapter

Concentric

see Table on page 8.

Minimum length is 5 ft (1.5M).

Heater

Side View

6 ft (1.8M) minimum

Adjoining Building

Form RZ-NA I-SCE, Page 14

3 ft (1M) minimum

6-15/16

(176mm)

3 ft (1M) minimum

Building Projection

Exhaust (Vent) Cap IMPORTANT: Install exhaust cap so the baffles are positioned at 12:00, 3:00, 6:00, and 9:00 oclock.

Double-Wall

Vent Pipe -

Pitch to

Drain

Inlet Air

Guard

Wall

Combustion Air Pipe Pitch to Drain

Concentric Adapter Box

Thimble

Page 15

VERTICAL VENT INSTRUCTIONS

Components Required - Factory and Field

Parts in the Vertical Vent Terminal/Combustion Air Package (Option CC2)

Qty P/N De s cription

1 205896 Complete Vertical Vent Kit (Same as Option CC2) 1 205885 Concentric Adapter Box Assembly (See 1 53326 Exhau st (Vent) Terminal (illus trated below) 1 53330 Co mbu s tion Air (illus trat ed below) 2 207232 Brackets for attaching Concentric Adapter Box (See 1 53335 Tube of High Temperature Silicone Sealant

Exhaust (Vent) Terminal, P/N 53326

Combustion Air Inlet, P/N 53330

FIGURE 1 0

, page 10)

FIGUR E 1 4

, belo w.)

Field-supplied installation requirements:

Installation Instructions for Vertical Vent/ Combustion Air Kit Option CC2

• Vent pipes - see requirements, page 8.

• Combustion air pipes - see requirements, page 8.

• Taper-type pipe diameter reducers and/or increasers as required.

• Thimble (a thimble is not required if wall is of non-combustible construction).

• Flashing.

• Sheetmetal screws, tape, and sealant as required.

1. Determine the location of the vent terminal.

Select a location away from fresh air intakes, allowing space for the concentric adapter box inside. Vent terminal must be located from adjacent buildings as shown in FIGURE 18, page 17.

If more than one vertical concentric vent/combustion air terminal (Option CC2) is being installed, the minimum spacing between vent centerlines is determined by the minimum outdoor design temperature (most extreme outdoor condition at the installation site).

Mi ni mum Ou tdo or Des i g n

Temperature

°F °C inches

31 or warmer 0 o r warmer 36 914

-10 to 30 -23 to -1 60 1524

less than -10 less than -23 84 2134

2. Install the Vent Pipe and Combustion Air Pipe Run - Use the type of pipe specified (Requirement No. 1, page 8), and comply with the attachment requirements in Requirement No. 2 and No. 4, page 8. Length must comply with Requirement No. 3, page 8.

Seal all joints. Due to the high temperature, do not enclose the exhaust pipe or place pipe closer than 6" (152 mm) to combustible material. Provide supports for the pipes. Extend the runs to close to the roof at the location selected in Step 1 above.

3. Prepare a hole through the roof for the 8" (203mm) diameter combustion air pipe. A thimble may or may not be required depending on building construction and/or local codes. The larger diameter combustion air pipe serves as clearance for the vent pipe on non-combustible construction.

4. Prepare the Concentric Adapter Box a) Attach the brackets to the box. Follow the instructions in FIGURE 14.

2) Attach the Box to the Roof (Step 5)

When the box is attached to the roof in Step 5, use the

2-1/2 (64mm) portion of the brackets. To adjust to

construction each bracket has three 7/32 diameter holes.

Minimum S pacing between Centerlines of Vent Pipes in

Vertical Combustion Air/Vent Terminals (Option CC2)

FIGURE 14 - Brackets for Attaching the Concentric Adapter Box to the Roof

1) Attach the Brackets to the Box - The 6 (152mm) portion of each bracket is designed with five 7/32 diameter holes so that attachment to the box can be adjusted.

If the roof is combustible, position brackets to allow for a 2 (51mm) clearance between the box and the roof.

After careful positioning, use sheetmetal screws to attach the brackets. NOTE: If any holes are made in the box in error, they must be sealed.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 15

Page 16

VERTICAL VENT INSTRUCTIONS (cont’d)

FIGURE 15 - Assemble Concentric Adapter Box, Outdoor Combustion Air Pipe, and Double-Wall Vent Pipe

b). Attach the outside portion of the combustion air pipe to the box. Determine the length of

the combustion air pipe so that dimension ”X” in FIGURE 15 is equal to the bracket length, plus the roof thickness, plus anticipated snow depth, but does not exceed 48“ (1219mm) or have less than 18” (457mm) of pipe above the roof. Attach the inlet air pipe to the collar of the concentric adapter box with sheetmetal screws.

A second section of double-wall pipe is permitted, joining the long continuous piece of vent pipe a minimum of 3 (76mm) above the top of the combustion air pipe.

3 (76mm) minimum

Vent pipe extending through the box and the combustion air pipe MUST be one continuous piece of doublewall vent pipe.

pipe must not exceed 48 (1219mm).

Extend length of double-wall

22 (559mm) minimum

Cold Climate NOTE:

In geographic areas where

the design ambient is -10°F

or lower, this minimum

height is 34 (864mm).

X = length of

combustion air pipe required

through and above the roof.

Height from box to top of inlet air

Minimum height above the roof is

18 (457mm) and must be higher

than anticipated snow depth.

Double-Wall Vent Pipe -

vent pipe a maximum of 6

(152mm) below the box.

After box is installed, install Concentric Vent Pipe One piece of continuous double-wall pipe must extend from a minimum of 3 (76mm) above the outer combustion air pipe to a maximum of 6 (152mm) below

the box. (NOTE: Vent pipe does not attach to the box; it must be supported.)

Vent Flow

1) Calculate height (see requirements on the left).

2) Be sure vent flow marking on pipe is in the right

direction.

3) Slide pipe through the box and the outer inlet air pipe.

4) Attach to vent run no more than 6 (152mm) from the

adapter box. See instructions on page 9.

First, attach Combustion Air Pipe and install the Concentric Box

1) Determine length (X) of pipe (see requirements

on the left).

2) Attach the pipe to the collar on the box.

3) Attach the brackets to the roof.

Mounting Brackets

Concentric Adapter Box

Collar for Indoor Portion of the Combustion Air Pipe

FIGURE 16 - Slide attached Combustion Air Pipe up through the Roof

Snow Clearance

18 (457mm) minimum

(NOTE: Maximum

from concentric adapter

box is 48 (1219mm)

Outside view with concentric adapter box attached to underside of roof. Install field-supplied flashing at roof opening.

Form RZ-NA I-SCE, Page 16

5. Attach the concentric adapter box to the roof. On the inside, insert the combustion air

pipe up through the opening and attach brackets to the roof. (See FIGURES 15 and 16.) On the outside, flash the combustion air pipe to the roof. Flashing is field supplied.

6. Determine the length and install the double-wall vent pipe. a) Determine the length. See FIGURE 15 to determine the required length of the vent pipe.

The vent pipe extending through the box and the inlet air pipe must be one piece of doublewall vent pipe without joints.

Determine the length by adding the requirements. Starting at the top, the vent pipe must extend a minimum of 22” (559mm) beyond the top of the inlet air pipe; plus the width of the roof; plus length of brackets; plus 6” (152mm) through the box; plus 6” (152mm) extending out of the box on the heater side.

b) Install the pipe. Being sure the pipe is in the proper flow direction, slide the end into the box and out through the combustion air pipe. Position the vent pipe to the lengths determined above. NOTE: The double-wall vent pipe does not attach to the box. The installer

must provide support.

Follow the instructions in FIGURE 9 , page 9, for connecting the double-wall pipe to the single-wall pipe or Category III vent pipe run. A taper-type reducer is required.

Seal the circumference of the pipe and the opening of the box with silicone sealant. Seal the area around the pipe completely.

Page 17

FIGURE 17 - Install Combustion Air Inlet and Vent Terminal

SECOND, Install the Exhaust (Vent) Terminal. Follow the instructions in FIGURE 8, page 9.

12 (305mm) minimum Cold Climate NOTE: In geographic areas where

the design ambient is -10°F or lower, this minimum height is 24 (610mm)

5 Inside Diameter

Double-wall Vent Pipe

FIRST, Install Combustion Air Inlet.

1) Slide the combustion air inlet over the vent pipe.

2) Fasten bottom of inlet to the combustion air pipe with sheetmetal screws. Be sure not to penetrate the vent pipe.

3) At the top, completely seal the space between the vent pipe and the air inlet with silicone.

8 Diameter Single-wall Combustion Air Pipe

Installation of the vertical vent and combustion air system on your separated-

FIGURE 18 - Installation of Unit with Vertical Vent Terminal/

combustion unit is complete. Verify compliance with all venting installation requirements, pages 8-11, and FIGURE 18 below.

Combustion Air Inlet (Option CC2)

7. On the outside, slide the combustion air inlet

over the vent pipe and fasten the collar to the combustion air pipe with sheetmetal screws. See FIGURE 17. Seal the opening at the top between the vent pipe and the combustion air inlet with silicone sealant to prevent water leakage.

8. Attach the exhaust (vent) cap. Follow the illustrated instructions in FIGURE 8 , page 9.

9. Attach the indoor combustion air pipe. Use sheetmetal screws to attach the single-wall combustion air pipe run to the collar on the concentric adapter box.

If using 7” pipe on Sizes 200-400, install a taper type enlarger as illustrated in FIGURE 11, page

11.

Seal joint with tape or sealant.

Rear View

Flashing (field-supplied)

Roof

Vent (flue exhaust) Terminal

Double-wall Vent (flue exhaust) Pipe

Seal with silicone sealant supplied with the kit.

Combustion Air Inlet

Shaded area represents required continuous (no joints) section of doublewall vent pipe. Section of pipe may extend higher.

Side View

6 ft (1.8M) minimum

Wall or Adjoining Building

Flashing

(field-supplied)

2 (51mm) if roof is combustible

Attach box to roof with brackets.

Roof

9-3/8 (238mm)

12 (305mm) minimum Cold Climate NOTE:

In geographic areas where the design ambient is -10°F

or lower, this minimum height is 24 (610mm).

11 (279mm)

*18

(457mm)

minimum

(Top of Box)

Concentric Adapter Box

4 ft (1.2M) maximum

Combustion

Air Pipe

Concentric Adapter Box

One-piece of Double-Wall Vent Pipe

Use taper-type reducer to attach to vent run a maximu



*Inlet air cap must be at least 6 higher than anticipated snow depth.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 17

Page 18

10. Gas Piping and Pressures

WARNING

This appliance is equipped for a maximum gas supply pressure of 1/2 psi, 3.5 kPa, or 14 inches water column. NOTE: Supply pressures higher than 1/2 psi require installation of an additional service regulator external to the unit.

Pressure Testing Supply Piping

Test Pressure Above 1/2 PSI: Disconnect the heater and manual valve from the gas supply

which is to be pressure tested. Cap or plug the supply line.

Test Pressure Below 1/2 PSI: Before testing, close the manual valve on the heater.

WARNING: Manifold gas pressure must never exceed 3.5" w.c. for natural gas or 10" w.c. for propane gas.

All piping must be in accordance with requirements outlined in the National Fuel Gas Code ANSI/Z223.1 (latest edition) or CSA B149.1 and B149.2 (See Paragraph 1.) Gas supply piping installation should conform with good practice and with local codes. These separated-combustion units for natural gas are orificed for gas having a heating value of 1000 (±50) BTUH per cubic ft. If the gas at the installation does not meet this specification, consult the factory for proper orificing.

Seal the opening for the gas supply pipe with the grommet provided.

Pipe joint compounds (pipe dope) shall be resistant to the action of liquefied petroleum gas or any other chemical constituents of the gas being supplied. Install a ground joint union and manual shutoff valve upstream of the unit control system. The 1/8" plugged tapping in the shutoff valve provides connection for supply line pressure test gauge. The National Fuel Gas Code requires the installation of a trap with a minimum 3" drip leg. Local codes may require a longer drip leg, typically 6" (See FIGURE 19.).

WARNING: All components of a gas supply system must be leak tested prior to placing the equipment in service. NEVER TEST FOR LEAKS WITH AN OPEN FLAME. See Hazard Levels, page 2.

FIGURE 19 - Gas Connection

Form RZ-NA I-SCE, Page 18

Gas Connection (Standard Unit)

Model Size 125-250 300-400 Natural Gas 1/2" 3/4" Propane Gas 1/2" 1/2"

NOTE: The above are gas connection sizes; not supply line sizes.

After all connections are made, disconnect the pilot supply at the control valve and bleed the system of all air. Reconnect the pilot line and leak test all connections by brushing on a soap solution.

6 I.D. Combustion Air Inlet Collar

6O.D. Vent Connection

Control Side View

Seal with Grommet

1-1/2 (38)

Ground Joint Union

A manual shutoff valve with 1/8 NPT plugged tap, accessible for test gauge connection, must be installed immediately upstream of the gas supply connection.

2-3/4 (70)

Drip Leg

Page 19

Sizing Gas Supply Lines

Length Diameter of Pipe

of 1/2" 3/4" 1" 1-1/4" 1-1/2" 2"

Pipe Natural Pro pane Natural Pro pane Natural Pro pane Natural Pro pane Natu ral Propane Natu ral Propane

20' 92 56 190 116 350 214 730 445 1100 671 2100 1281 30' 73 45 152 93 285 174 590 360 890 543 1650 1007 40' 63 38 130 79 245 149 500 305 760 464 1450 885 50' 56 34 115 70 215 131 440 268 670 409 1270 775 60' 50 31 105 64 195 119 400 244 610 372 1105 674 70' 46 28 96 59 180 110 370 226 560 342 1050 641 80' 43 26 90 55 170 104 350 214 530 323 990 604

90' 40 24 84 51 160 98 320 195 490 299 930 567 100' 38 23 79 48 150 92 305 186 460 281 870 531 125' 34 21 72 44 130 79 275 168 410 250 780 476 150' 31 19 64 39 120 73 250 153 380 232 710 433 175' 28 17 59 36 110 67 225 137 350 214 650 397 200' 26 16 55 34 100 61 210 128 320 195 610 372

Note: When sizing sup ply lines, consider pos sibilit ies of future exp ansion and increased requirements.

Capacity of Piping

Cubic Feet p er Hour based on 0.3" w .c. Pressure Drop

Specific Gravity for Natural Gas -- 0.6 (Natural Gas -- 1000 BTU/Cubic Ft)

Specific Gravity for Propane Gas -- 1.6 (Propane Gas -- 2550 BTU/Cubic Ft)

Refer to National Fuel Gas Code for additional information on line siz ing.

Manifold or Orifice (Valve Outlet) Pressure Settings

Measuring manifold gas pressure cannot be done until the heater is in operation. It is included in the steps of the "Check-Test-Start" procedure in Paragraph 25. The following warnings and instructions apply. For Natural Gas: When the heater leaves the factory, the combination valve is set so that the outlet gas pressure of a single-stage valve or high fire of a two-stage valve is regulated to

3.5" w.c. Low fire on a two-stage valve is set to 1.8" w.c. Inlet supply pressure to the valve must be a minimum of 5" w.c. or as noted on the rating plate and a maximum of 14" w.c. NOTE: Always check the rating plate for minimum gas supply pressure. Minimum supply pressure requirements vary based on size of burner and the gas control option. Most units require a minimum of 5" w.c. of natural gas as stated above, but Sizes 350 and 400 with electronic modulation require a minimum of 6" w.c. natural gas supply pressure. Sizes 300 and 350 with mechanical modulation require 7" w.c.

For Propane Gas: When the heater leaves the factory, the combination valve is set so that the outlet gas pressure of a single-stage valve or high fire of a two-stage valve is 10" w.c. Low fire on a two-stage valve is set to 5" w.c. Inlet pressure to the valve must be a minimum of 11" w.c. and a maximum of 14" w.c. Before attempting to measure or adjust manifold gas pressure, the inlet (supply) pressure must be within the specified range for the gas being used both when the heater is in operation and on standby. Incorrect inlet pressure could cause excessive manifold gas pressure immediately or at some future time.

Instructions to Check Valve Outlet (Manifold) Pressure:

1) With the manual valve (on the combination valve) positioned to prevent flow to the main burners, connect a manometer to the 1/8" pipe outlet pressure tap in the valve. NOTE: A manometer (fluid-filled gauge) is recommended rather than a spring type gauge due to the difficulty of maintaining calibration of a spring type gauge.

2) Open the valve and operate the heater. Measure the gas pressure to the manifold. To measure the low stage pressure on units equipped with a two-stage valve, disconnect the wire from the "HI" terminal on the valve. (Be sure to reconnect the wire.) Normally adjustments should not be necessary to the factory preset regulator. If adjustment is necessary, set pressure to correct settings by turning the regulator screw IN (clockwise) to increase pressure. Turn regulator screw OUT (counterclockwise) to decrease pressure. Consult the valve manufacturer's literature provided with the furnace for more detailed information.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 19

Page 20

11. Electrical Supply and Connections

All electrical wiring and connections including electrical grounding must be made in accordance with the National Electric Code ANSI/NFPA No. 70 (latest edition) or, in Canada, the Canadian Electrical Code, Part I-CSA. Standard C22.l. Check any local ordinances or gas company requirements that apply.

Check the rating plate on the heater for the supply voltage and the current requirements. A separate line voltage supply with fused disconnect switch should be run directly from the main electrical panel to the unit, making connections in the junction box. Refer to FIGURE 1, Paragraph 3. Seal all electrical entrance openings with field-supplied bushings.

Field-Supplied Wiring Size from Disconnect to Electrical Box for

Connection to Motor Contactor or Starter

Voltag e/ Phas e Motor HP Wire Gauge BX Cable

120/1 1/4 - 1/2 14 3/8"

1123/8" 208-230/ 1 1 - 1-1/ 2 14 3/8" 208-230/ 3 1/4 - 3 14 3/ 8"

5123/8"

460/3 1/4 - 5 14 3/8" 575/3 1/2 - 5 14 3/8"

CAUTION: If any of the original wire as supplied with the appliance must be replaced, it must be replaced with wiring material having a temperature rating of at least 105°C, except for sensor lead and optional bypass damper combustion air safety circuit (Option AG39 or AG40) wires which must be 150°C. See Hazard Levels, page 2.

12. Control Thermostat

A disconnect switch is available as optional equipment or may be supplied locally. When installing the disconnect switch, be careful that the conduit and switch housing are clear of all service panels. Allow at least four feet (1.2M) of service room between the disconnect switch and any removable service panels. When providing or replacing fuses in a fusible disconnect switch, use dual element time delay fuses and size 1.25 times the maximum total input amps.

The heater is equipped with a low voltage (24V) control circuit. See the typical wiring diagrams on pages 21 and 22; a specific wiring diagram can be found in the heater junction box. See separate instruction sheets for any optional equipment provided. Optional equipment is identified on the wiring diagram supplied with the heater.

Field Control Wiri ng - Length and Gauge

Total Wire

Le n gt h

150ft (46M) 75ft (23M ) #18 ga uge 250ft (76M) 125ft (38M) # 16 gauge

350ft (107M) 175ft (53M ) # 14 gaug e

A thermostat is not supplied with the furnace. Use either an optional or a field-provided lowvoltage (24V) thermostat. Install the thermostat according to the manufacturer's instructions.

A low voltage thermostat is equipped with a heat anticipator which levels out unit cycling for optimum temperature control. Set the anticipator at 1.0 amps for standard controls. See chart below for amp ratings of optional controls.

Distance from

Unit to Control

Minimum Recommended

Wi re Gau ge

Form RZ-NA I-SCE, Page 20

CAUTION: Control circuit amps should be within the anticipator amp rating of the thermostat used.

Ampere Rating of 24-Volt Controls

Fan Control ............................... .12 amps

Time Delay Heater ..................... .14 amps

RBM Relay Coil ......................... .12 amps

Contactor Coil ........................... .45 amps

Spark Ignition System ............... .1 amps

Maxitrol Gas Control System .... .51 amps

Honeywell Gas Valve ................ .5 amps

White-Rodgers Gas Valve ......... .6 amps

Page 21

Typical Wiring Diagrams

FIGURE 20 - W. D. 225711, Model SCE with Single-Stage Gas Control

DISCONNECT SWITCH

(SEE NOTE)

LINE

1/60 OR 3/60

GRD

TIME DELAY

BK BK BK BK

B C W

BL BR

OPTIONAL SP/ST

S/W SWITCH

BK BK

RELAY CONTACTS

1 3

FAN TD

CONTACTS

1 3

BLOWER MOTOR

CONTACTOR

CONTACTS

LINE VOLT

24V

R OR BK

R OR W

40 VA. CONTROL

TRANSFORMER

INTERNALLY PROTECTED

BLOWER

MOTOR

YBKBK

VENTER MOTOR

& CAPACITOR

WIRING CODE BLACK - BK BROWN - BR RED - R ORANGE - O YELLOW - Y GREEN - G BLUE - BL PURPLE - PR WHITE - W

16 CR

W19

HTDH

BLOWER MOTOR CONTACTOR COIL

7 - 8 - 9

TIME DELAY RELAY COIL

12 - 24

FIELD CONTROL WIRING TOTAL WIRE MINIMUM RECOMMENDED LENGTH WIRE SIZE 150 FEET #18 GA. 250 FEET #16 GA. 350 FEET #14 GA.

OPERATING SEQUENCE

1. SET THERMOSTAT AT LOWEST SETTING.

2. TURN ON POWER, MAIN AND MANUAL GAS VALVE.

3. SET THERMOSTAT AT DESIRED SETTING.

4. THERMOSTAT CALLS FOR HEAT. (A) ENERGIZING THE VENTER MOTOR AFTER A 15 SECOND (APPROX.) TIME DELAY.

5. VENTER FLOW SWITCH SWITCHES TO N.O. POSITION AND POWERS THE IGNITION

CONTROLLER. WITH POWER SUPPLIED TO THE IGNITION CONTROLLER THE PILOT GAS VALE IS ENERGIZED AND PILOT LIGHTS FROM IGNITOR, AFTER A TIME DELAY PRE-PURGE (10-15 SECONDS ).

6. IF THE FLAME IS EXTINGUISHED DURING MAIN BURNER OPERATION THE SAFETY SWITCH

CLOSES THE MAIN VALVE AND RECYCLES THE SPARK GAP. ON UNIT EQUIPPED WITH G770NGC-4 LOCKOUT CONTROL, IF PILOT IS NOT ESTABLISHED WITHIN 120 SEC. (APPROX.) UNIT LOCKS OUT AND MUST BE RESET BY INTERRUPTING POWER TO CONTROL CIRCUIT (SEE LIGHTING INSTRUCTIONS.)

7. THE SENSING PROBE PROVES THE PRESENCE OF THE PILOT FLAME. (A) DE-ENERGIZING THE IGNITOR. (B) ENERGIZING THE MAIN GAS VALVE. (C) BLOWER MOTOR OPERATES FROM FAN TIME DELAY.

8. WHEN THERMOSTAT IS SATISFIED. (A) MAIN GAS VALVE IS DE-ENERGIZED. (B) PILOT GAS VALVE IS DE-ENERGIZED. (C) IGNITION CONTROLLER IS DE-ENERGIZED. (D) TIME DELAY RELAY KEEPS VENTER MOTOR ON FOR APPROX. 90 SEC. (POST PURGE).

9. SET THERMOSTAT SYSTEM SWITCH AT "OFF" POSITION FOR SHUTDOWN. (A) BLOWER MOTOR REMAINS ON AS DETERMINED BY FAN TIME DELAY.

SET ANTICIPATOR AT 1.0 AMPS

OPTIONAL SINGLE STAGE THERMOSTAT

TIME DELAY

RELAY CONTACTS

4 5

COMBUSTION

PRESSURE

SWITCH

COM

FACTORY WIRING

FIELD WIRING

OPTIONAL FACTORY WIRING

OPTIONAL FIELD WIRING

LIMIT

CONTROL

G67BG-5

RECYCLE

LOCKOUT

IGNITION

CHASSIS GRND.

GRND.

STRIP

FLAME SENSING

PROBES

IGNITOR

GRND

1, 2, 4, 7, 8, 10, 11, 12, B, C & W

HONEYWELL

REDUNDANT GAS VALVE

FAN TD HEATER 16

MAIN

PILOT

H TD H

TR OR PV-MV

MAIN

TH OR

PILOT

TH-TR OR PV

TERMINAL BLOCK -- HEATER COMPARTMENT

G770NGC-4

CONTROLLER

NOTES

1. THE FOLLOWING CONTROLS ARE SUPPLIED BY REZNOR FOR FIELD INSTALLATION: NONE

2. THE FOLLOWING CONTROLS ARE SUPPLIED AS OPTIONAL EQUIPMENT: THERMOSTAT AND S/W SWITCH

3. DOTTED WIRING AND THE FOLLOWING CONTROLS ARE SUPPLIED AND INSTALLED BY OTHERS: NONE

4. CAUTION: IF ANY OF THE ORIGINAL WIRE AS SUPPLIED WITH THE APPLIANCE MUST BE REPLACED, IT MUST BE REPLACED WITH WIRING MATERIAL HAVING A TEMPERATURE RATING OF AT LEAST 105 DEGREES C., EXCEPT FOR SENSOR LEAD WIRE WHICH MUST BE 150 DEGREES C.

5. LINE AND BLOWER MOTOR BRANCH CIRCUIT WIRE SHOULD BE SIZED TO

PREVENT VOLTAGE DROP BEYOND FIVE PERCENT OF SUPPLY LINE VOLTAGE.

6. USE #14 GA. WIRE FOR LINE AND MOTOR WIRING ON 3 PHASE UNIT.

7. USE #12 GA. WIRE FOR LINE AND MOTOR WIRING ON SINGLE PHASE UNIT.

8. USE #18 GA. WIRE FOR 24 VOLT CONTROL WIRING ON UNIT.

9. ON 208/230V. UNITS THE CONTROL TRANSFORMER HAS A DUAL VOLTAGE PRIMARY. FOR 230V. UNITS USE BLACK AND YELLOW LEADS (CAP RED). FOR 208V. UNITS USE BLACK AND RED LEADS (CAP YELLOW).

ON 115/460V. UNITS THE CONTROL TRANSFORMER IS A SINGLE VOLTAGE PRIMARY.

FOR 115/460V. UNITS USE BLACK AND YELLOW LEADS.

10. WHEN PROVIDING OR REPLACING FUSES IN THE FUSIBLE DISCONNECT SWITCH USE DUAL ELEMENTS TIME DELAY FUSES AND SIZE ACCORDING TO 1.25 TIMES THE MAXIMUM TOTAL INPUT AMPS.

11. DISCONNECT SWITCH IS FIELD FURNISHED OR AVAILABLE FROM FACTORY AS AN OPTION.

MAIN

PILOT

REDUNDANT GAS VALVE

ALTERNATE W.R. OR ROBERTSHAW

225711

SCB-SCE: AH2/AH3-AN2-BF4-CL1 DWG. #225711

IJB

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 21

Page 22

Typical Wiring Diagrams (cont'd)

FIGURE 21 - W. D. 225636, Model SCE with Two-Stage Gas Control

DISCONNECT SWITCH

LINE

1/60 OR 3/60

BK BK BK BK

BC W

BK Y

(SEE NOTES)

GRD

TIME DELAY

RELAY CONTACTS

1 3

BLOWER MOTOR

CONTACTOR

CONTACTS

LINE VOLT

24V

R OR BK

R OR W

40 VA. CONTROL

TRANSFORMER

INTERNALLY

PROTECTED

BLOWER

MOTOR

WBKBK

VENTER MOTOR

& CAPACITOR

WIRING CODE BLACK - BK BROWN - BR RED - R ORANGE - O YELLOW - Y GREEN - G BLUE - BL PURPLE - PR WHITE - W

OPTIONAL

FIELD CONTROL WIRING

TOTAL WIRE M INIMUM RECOMMENDED LENGTH WIRE SIZE 150 FEET #18 GA. 250 FEET #16 GA. 350 FEET #14 GA.

BL R

SET ANTICIPATOR AT 1.0 AMPS

T874F THERMOSTAT Q674G SUBBASE

FAN TD

CONTACTS

1 3

OPTIONAL SP-ST

SUMMER/WINTER SWITCH

(ADD RH-RC

JUMPER)

BKBK

108

G67BG-5 RECYCLE

G770NGC-4

LOCKOUT

IGNITION

CONTROLLER

CHASSIS GRND.

GRND.

STRIP

FLAME SENSING

IGNITOR

PROBES

GRND

RELAY CONTACTS

COMBUSTION

FACTORY WIRING

FIELD WIRING

TIME DELAY

4 5

PRESSURE

SWITCH

COM

LIMIT

CONTROL

1, 2. 4, 7, 8, 10, 11,

12, 13, B, C & W

19 CR

W22

HTDH

H TD H

STG

LOW

PILOT

STG

HIGH

TERMINAL BLOCK -- HEATER COMPARTMENT

HONEYWELL TWO STAGE

REDUNDANT GAS VALVE

BLOWER MOTOR CONTACTOR COIL

7 - 8 - 9

TIME DELAY RELAY COIL

12 - 27

FAN TD HEATER

LOW STAGE

PILOT

HIGH STAGE

STG

LOW

PILOT

STG

HIGH

REDUNDANT GAS VALVE

ALTERNATE W.R. TWO STAGE

OPTIONAL FACTORY WIRING

OPTIONAL FIELD WIRING

OPERATING SEQUENCE

1. SET THERMOSTAT SYSTEM SWITCH AT "OFF" POSITION.

2. TURN ON POWER AND MANUAL GAS VALVES TO UNIT.

3. SET THERMOSTAT SYSTEM SWITCH AT "AUTO" POSITION. (A) FIRING RATE IS CONTROLLED BY THE TWO STAGE THERMOSTAT. (B) THE BLOWER OPERATES FROM THE FAN TIME DELAY.

4. SET SYSTEM SWITCH AT "OFF" POSITION FOR SHUTDOWN.

(A) BLOWER MOTOR REMAINS ON AS DETERMINED BY FAN TIME DELAY.

5. SET SUMMER/WINTER SWITCH AT "ON" POSITION FOR CONTINUOUS BLOWER OPERATION.

FIRING SEQUENCE:

1. ON A CALL FOR HEAT BY THE LOW STAGE OF THERMOSTAT. (A) THE VENTER MOTOR IS ENERGIZED AFTER A 15 SECOND (APPROX.) TIME DELAY.

(B) VENTER FLOW SWITCH SWITCHES FROM N.C. TO N.O. CONTACTS ENERGIZING THE PILOT GAS VALVE AND SPARK TO PRODUCE A PILOT FLAME ON EACH OPERATING CYCLE. THE SENSING PROBE PROVES THE PRESENCE OF THE PILOT FLAME AND ENERGIZES THE SAFETY PORTION OF THE CONTROL. THE SWITCH ACTION DE-ENERGIZES THE SPARK GAP AND ENERGIZES THE MAIN VALVE. THE MAIN GAS IGNITES AND UNIT FIRES AT LOW RATE.

2. ON A CALL FOR HEAT BY THE HIGH STAGE OF THERMOSTAT, THE UNIT FIRES AT FULL RATE.

3. IF THE FLAME IS EXTINGUISHED DURING MAIN BURNER OPERATION THE

SAFETY SWITCH CLOSES THE MAIN VALVE AND RECYCLES THE SPARK GAP.

ON UNIT EQUIPPED WITH G770NGC-4 LOCKOUT CONTROL, IF PILOT IS

NOT ESTABLISHED WITHIN 120 SECONDS (APPROX.), THE UNIT LOCKS OUT

AND MUST BE RESET BY INTERRUPTING POWER TO CONTROL CIRCUIT

(SEE LIGHTING INSTRUCTIONS).

225636

SCE: AH2/AH3 AG2-CL7-CH1 DWG. #225636

Form RZ-NA I-SCE, Page 22

RSM

NOTES

1. THE FOLLOWING CONTROLS ARE SUPPLIED BY REZNOR FOR FIELD INSTALLATION: NONE

2. THE FOLLOWING CONTROLS ARE SUPPLIED AS OPTIONAL EQUIPMENT:

THERMOSTAT AND SUMMER/WINTER SWITCH

3. DOTTED WIRING AND THE FOLLOWING CONTROLS ARE SUPPLIED AND INSTALLED

BY OTHERS: NONE

4. CAUTION: IF ANY OF THE ORIGINAL WIRE AS SUPPLIED WITH THE APPLIANCE MUST BE REPLACED, IT MUST BE REPLACED WITH WIRING MATERIAL HAVING A TEMPERATURE RATING OF AT LEAST 105° C. EXCEPT FOR SENSOR LEAD WIRE WHICH MUST BE 150° C.

5. LINE AND BLOWER MOTOR BRANCH CIRCUIT WIRE SIZES SHOULD BE OF A SIZE TO PREVENT VOLTAGE DROP BEYOND FIVE PERCENT OF SUPPLY LINE VOLTAGE.

6. USE #14 GA. WIRE FOR LINE AND MOTOR WIRING ON 3 PHASE UNIT.

7. USE #12 GA. WIRE FOR LINE AND MOTOR WIRING ON SINGLE PHASE UNIT.

8. USE #18 GA. WIRE FOR 24 VOLT CONTROL WIRING ON UNIT.

9. ON 208/230V. UNITS THE CONTROL TRANSFORMER HAS A DUAL VOLTAGE PRIMARY.

FOR 230V. UNITS USE BLACK AND YELLOW LEADS (CAP RED). FOR 208V. UNITS USE BLACK AND RED LEADS (CAP YELLOW). ON 115/460V. UNITS THE CONTROL TRANSFORMER IS A SINGLE VOLTAGE PRIMARY. FOR 115/460V. UNITS USE BLACK AND YELLOW LEADS.

10. WHEN PROVIDING OR REPLACING FUSES IN THE FUSIBLE DISCONNECT SWITCH USE DUAL ELEMENTS TIME DELAY FUSES AND SIZE ACCORDING TO 1.25 TIMES THE MAXIMUM TOTAL INPUT AMPS.

11. DISCONNECT SWITCH IS FIELD FURNISHED OR AVAILABLE FROM FACTORY AS AN OPTION.

Page 23

13. Combustion Air Proving Switch

The combustion air proving switch ensures that proper combustion airflow is available. The switch is a single-pole, double-throw switch, which senses pressure caused by the flow of combustion air from the venter. The switch is designed to close when a decreasing pressure is sensed in the outlet duct of the gas collection box.

On startup when the furnace is cold, the sensing pressure is at the most negative level, and as the furnace and the flue system warm-up, the sensing pressure becomes less negative. After the system has reached equilibrium (approximately 20 minutes), the sensing pressure levels off. If a restriction or excessive flue length or turns cause the sensing pressure to become less than the switch setpoint, the pressure switch will function to shut off the main burners. The main burners will remain off until the system has cooled and/or the flue system resistance is reduced. The table below gives approximate water column negative pressure readings and switch setpoints for sea level operating conditions.

Startup Cold Equilibrium Factory Setpoint

-1.0" w.c. -.70" w.c. -.58 +or- .05" w.c.

NOTE: These settings apply to furnaces that are not equipped with air and gas modulation Option AG39 or AG40. For pressure switch settings for units equipped with Option AG39 or AG40, see Paragraph 21.

DANGER: Safe operation requires proper venting flow. Never bypass the combustion air proving switch or attempt to operate the unit without the venter running and proper flow in the vent system. Hazardous condition could result. See Hazard Levels, page 2.

14. Fan Control

Service NOTE: To replace the fan control on units manufactured prior to 11/04, a replacement kit is required. Order P/N 209184.

15. Limit Control

16. Motor Loads and

Amps

1. A fan control provides for the following control of the blower. (a) After the gas valve opens, there is a time delay of blower operation to prevent the

discharge of cold air. (b) Blower operation continues after the thermostat is satisfied as determined by the fan time delay.

2. To be sure that the blower can continue to operate, the power supply to the furnace

MUST NOT be interrupted except when servicing the unit.

3. If the customer wants the furnace off at night, the gas valve circuit SHOULD BE

OPENED by a single pole switch wired in series with the thermostat. Some thermostats are provided with this feature. Multiple units controlled from a single thermostat are shut off in the same manner. For proper operation, be sure the fan control wiring is observed.

All models are equipped with an automatic, non-adjustable reset limit control that acts to interrupt the electric supply to the redundant main operating valve in case of motor failure or lack of airflow due to restrictions at the inlet or outlet.

Use an ammeter to check blower motor amps. The chart on the right lists full load amps of open-type blower motors by HP and voltage . Amps may be adjusted downward by reducing blower RPM or by increasing duct system static pressure.

This chart can be used for sizing line wiring but should not be interpreted as the exact motor amps. See the motor rating plate for exact motor specifications. Do not exceed amp rating on the motor nameplate.

Venter motor amps for a 115 volt or 575 volt unit are 1.5 amps; venter motor amps for a 208, 230, or 460 volt unit are .8 amps.

Full Load Amps - Blower Moto rs (Open)

(Single Speed- Average Values)

HP 1/4 1/3 1/2 3/4 1 1-1/2 2 3 5

115V 1PH 208V 1PH 230V 1PH 208V 3PH 230V 3PH 460V 3PH 575V 3PH

4.6 5.6 8.8 11.0 13.0 18.2 20.4 24.8 N/A

2.5 3.1 5.1 6.1 7.2 10.1 11.3 13.7 28.0

2.3 2.8 4.4 5.5 6.5 9.1 10.2 12.4 26.0

1.7 1.8 2.2 2.9 3.6 5.8 7.3 9.3 14.6

1.5 1.6 2.0 2.6 3.2 5.2 6.6 8.4 13.2

.75 .80

N/A N/A N/A N/A 1 .3 2.1 2 .6 3.4 5 .3

1.0 1.3 1.6 2.6 3.3 4.2 6.6

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 23

Page 24

17. Blowers, Belts and Drives

FIGURE 22 - Check Belt Tension

3/4 (19mm)

Check belt tension. Proper belt tension is important to the long life of the belt and motor. A loose belt will cause wear and slippage. Too much tension will cause excessive motor and blower bearing wear. Adjust the belt tension by turning the adjusting screw on the motor base until the belt can be depressed 3/4" (19mm). (See FIGURE 22.) After correct tension is achieved, re-tighten the locknut on the adjustment screw. Be sure that the belt is aligned in pulleys.

Adjusting Blower Speed

The blower speed may be adjusted to achieve the desired outlet temperature, as long as the adjustment is within the temperature rise and the static pressure limits shown on the furnace rating plate. Motors are factory set between maximum and minimum blower speeds. If the duct resistance is low, the blower may deliver too high an air volume. If the resistance is very low, the blower may deliver excess air to overload the motor, causing the overload protector to cycle the motor. Reducing the blower speed will correct these conditions. If ductwork is added to an installation, it may be necessary to increase the blower speed. Decreasing blower speed will increase outlet temperature; increasing blower speed will decrease outlet temperature.

At final adjustment, amperes should not exceed motor nameplate amp rating. The installation must be adjusted to obtain a temperature rise within the range specified on the furnace rating plate.

The belt drive on these units is equipped with an adjustable pulley which permits adjustment of the blower speed. Follow these instructions to adjust the blower speed.

1. Turn off the gas and the electric power.

2. Loosen belt tension and remove the belt.

3. Loosen the set screw on the side of the pulley away from the motor.

4. To increase the blower speed, decreasing outlet temperature, turn the adjustable half of the pulley inward. To decrease the blower speed, increasing the outlet temperature, turn the adjustable half of the pulley outward. One turn of the pulley will change the speed 8-10%.

5. Tighten the set screw on the flat portion of the pulley shaft.

6. Replace the belt and adjust the belt tension. Adjust tension by turning the adjusting screw on the motor base until the belt can be depressed 3/4". (See FIGURE 22.) Re-tighten the lock nut on the adjusting screw. Be sure that the belts are aligned in the pulley grooves properly and are not angled from pulley to pulley.

7. Turn on the gas and electric. Light the heater following the instructions on the lighting instruction plate.

8. Check the motor amps with an ammeter. The maximum motor amp rating on the motor nameplate must not be exceeded.

When service is complete, check for proper operation.

Blower Rotation

Optional Variable Frequency Drive

Form RZ-NA I-SCE, Page 24

Each blower housing is marked for proper rotation. Rotation may be changed on singlephase motors by re-wiring in the motor terminal box. Three-phase motors may be reversed by interchanging two wires on the 3-phase supply connections.

If the system is equipped with an optional variable frequency drive, the motor will operate on speeds as determined by the electrical frequency. 60 hertz is maximum speed. Speeds must be within the temperature rise range of a Model SCE Series 6 heater which is 30-90°F.

Follow the variable frequency controller manufacturer's instructions that are packaged with the heater (in the owner's envelope) to program the variable frequency drive settings. The formula for motor speed is N = 120 x f/p where N is speed; f is frequency; and p is number of poles (3600 RPM motor has 2 poles; an 1800 RPM motor has 4 poles).

Example: 1800 RPM motor on 60Hz; N = 120 x 60/4 = 1800

1800 is synchronous speed; assume 2% slip. Motor will run between 1750 and 1790 RPM at full load depending on design. Run the same motor at 45Hz (120 x 45/4 = 1350). 1350 RPM less 2% slip equals about 1300 RPM.

Page 25

18. Operating Valve

All furnaces are equipped with a 24-volt combination valve which includes the automatic electric on-off valve controlled by the room thermostat, the pressure regulator, the safety pilot valve, and the manual shutoff valve. The standard gas valve allows for single-stage control from a singlestage, 24-volt thermostat.

WARNING: The operating valve is the prime safety shutoff. All gas supply lines must be free of dirt or scale before connecting the unit to ensure positive closure. See Hazard Levels, page 2.

19. Optional 2Stage Operation Heating Only Application

20. Optional 2Stage Operation Makeup Air Application

FIGURE 23 - Duct Temperature Sensor Location

The standard combination control valve is replaced with a two-stage combination gas control valve providing for low fire or high fire operation controlled by a two-stage thermostat. First stage (low fire) is factory set (not field adjustable). Both high and low stages are controlled by a Servo regulator, maintaining constant gas input under wide variations in gas supply pressure. See instructions packed with the unit for specific gas valve specifications, wiring, and operating instructions.

Two-stage makeup air units are equipped with a two-stage gas valve, but instead of control from a two-stage room thermostat, the outlet air temperature is monitored and controlled by a twostage ductstat. When the discharge air temperature drops to the setpoint, low fire is energized. If low fire cannot satisfy the ductstat setting, high fire is energized.

Makeup air applications are usually adjusted to discharge an outlet air temperature between 65°F and 75°F. In all applications, the allowable temperature rise of the furnace in the installation dictates the limits of the ductstat temperature setting.

Depending on the option selection, the factory-installed sensor is either field-connected by capillary tubing to the unit-mounted ductstat (FIGURE 24) or electrically connected to a remote electronic temperature selector (FIGURE 25). The remote temperature selector is available with or without a display module.

See FIGURE 23 for a general location of the factory-installed sensor with either the factorymounted or the remote ductstat selector option.

1. Remove access panel in ductwork adjacent to control compartment access panel.

2. Element is retained by spring clips.

3. Round gasket and metal retaining

plate provide airtight seal for capillary and must be removed to remove the element.

Sheetmetal

Retaining

Plate

Gasket

Sensor Capillary

Sensor Bracket

(NOTE: Bracket

may not be the

same as the one

illustrated.)

FIGURE 24 - Ductstat Control in Options AG3

Factory set at 70°F

Optional Ductstat with Capillary Tubing (Option AG3) -- The control illustrated in FIGURE 24

has an adjustable range from 0° to 100°F with a fixed differential of 2-1/2°F. Due to different CFM settings and outside air temperatures, the average downstream outlet temperature may not match the ductstat setting exactly. After the installation is complete, adjust the setpoint of the ductstat to achieve the desired average outlet air temperature.

Optional Ductstat with Electronic Remote Setpoint Module (Options AG15 and AG16) -- The field-installed sensing probe is field-wired to a remote temperature selector with a temperature operating range to 130°F. The remote modules and sensing probe are shipped separately for field installation. Follow the wiring diagram with the unit and the manufacturer's instructions for wiring and installation. CAUTION: Be sure heat/cool selector switch is set at "Heat" position. There will be one module for selecting temperature and one-stage adder module. The digital display module is optional. See FIGURE 25.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 25

Page 26

20. Optional 2Stage Operation Makeup Air Application (cont'd)

FIGURE 25 - (A) Remote Temperature Selector, (B) Stage-Adder Module, and (C) Optional Display Module for Ductstat in Two-Stage Makeup Air Control Options (Option AG15 or AG16)

(A)

(B) (C)

21. Optional Electronic Modulation

FIGURE 26 - Maxitrol Signal Conditioner used in both Option AG21 and Option AG40

The type and capability of the electronic modulation system, depends on the option selected. Electronic modulation options are identified by a suffix to the Serial No. printed on the heater rating plate. AG7 is identified as MV-1; AG8 is identified as MV-3; AG9 is identified as MV-4; AG21 is identified as MV-A; AG39 is identified as MP-1; and AG40 is identified as MP-2. Installation NOTE: Sizes 350 and 400 with electronic modulation require a minimum of 6" w.c. natural gas supply pressure.

21A. Electronic Modulation between 50% and 100% Firing Rate

(Options AG7, AG8, AG9)

Depending on the heat requirements as established by the thermistor sensor, the burner modulates between 100% and 50% firing. The thermistor is a resistor that is temperature sensitive in that as the surrounding temperature changes, the Ohms resistance changes through the thermistor. This change is monitored by the solid state control center (amplifier) which furnishes varying DC current to the modulating valve to adjust the gas input.

Each modulating valve is basically a regulator with electrical means of raising and lowering the discharge pressure. When no DC current is fed to this device, it functions as a gas pressure regulator, supplying 3.5" w.c. pressure to the main operating valve.

Refer to the wiring diagram supplied with the furnace for proper wiring connections. Electronic modulation for heating controlled by a specially designed room thermostat (60°-85°F) is identified as Option AG7. Electronic modulation control systems for makeup air applications controlled by a duct sensor and temperature selector (55-90°F) are identified as either Option AG8 or Option AG9. The temperature selector setting for Option AG8 is on the amplifier; Option AG9 has a remote temperature selector. Both systems are available with an override thermostat.

21B. Computer Controlled Electronic Modulation between 50%

and 100% Firing Rate (Option AG21)

With this option the furnace is equipped with a Maxitrol signal conditioner which operates much the same way as the amplifier above to control the regulator valve. The conditioner accepts an input signal of either 4-20 milliamps or 0-10 volts from a customer-supplied control device such as a computer. With the dip switches on the conditioner in the "on" positions, the conditioner accepts a 4-20 milliamp signal. In the "off" positions, the conditioner accepts a 0-10V signal. The conditioner converts the signal to the 0 to 20 volt DC current required to control the modulating valve.

21C. Electronic

Modulation between 20 to 28% and 100% Firing Rate (U.S. Patent 6,109,255), Option AG39 -

not available on Size 350; available with natural gas

only

Form RZ-NA I-SCE, Page 26

Depending on the size, furnaces equipped with electronic modulation Option AG39 have a 2028% turndown ratio. The furnace will ignite at any input rate in the available range and will maintain average thermal efficiencies equal to or greater than the thermal efficiency at full fire.

Mode l S CE

with AG39 or

AG40

SCE 125 20% 25 - 125 3.9" w.c. 5" w.c. SCE 150 27% 40.3 - 150 3.7" w.c. 5" w.c. SCE 175 23% 40.3 - 175 3.7" w.c. 5" w.c. SCE 200 26% 51.8 - 200 3.9" w.c. 5" w.c. SCE 225 23% 51.8 - 225 3.9" w.c. 5" w.c. SCE 250 28% 69 - 250 4.0" w.c. 5" w.c. SCE 300 23% 69 - 300 4.0" w.c. 5" w.c. SCE 400 25% 100 - 400 4.4" w.c. 6" w.c.

Maxi mum Turndown

MB H In put

Range

Inlet Pressure to

Modulating Valve

(factory s et)

Gas S uppl y

Pressure Required

Page 27

The gas train includes a single-stage gas valve, a modulating valve, and two gas pressure switches. The burner rack is equipped with one flash carryover and a regulated gas lighter tube system. The carryover lighter tube receives its gas supply through the regulator, simultaneously with the gas to the burner. Control of the system is through a Maxitrol #ES410A amplifier with a corresponding remote temperature dial (Maxitrol #ES410TD).

FIGURE 27 - Option AG39 Manifold Arrangement

Description of the Operation of Option AG39

P rimary Gas

Flow Pressure

Switch

White Label

1.1 w.c.

Carryover

gugu

Regulator

Gas Flow Pressure Switch White Label

1.1 w.c.

Modulating

Valve

Note: Arrangement may vary slightly depending on gas valve; components are the same.

Single-Stage

Gas Valve

The gas supply (see pressure requirements in the table above) connects to the single-stage gas valve. To compensate for additional pressure loss through the modulating valve, the single-stage gas valve has a custom outlet pressure setting higher than when it is used on a standard gas manifold. The pilot tubing connects to the pilot port on the single-stage gas valve. When the valve receives a call for heat from the amplifier and pilot is established, gas flow from the singlestage valve goes to both the modulating valve and the regulated lighter tube system. When the signal from the amplifier to the modulating valve requires less-than-high fire operation, the modulating valve functions to lessen the gas flow to the burner to reduce the input rate to that required to maintain the desired temperature. When the input rate is reduced enough to decrease the gas pressure to 1.1" w.c., the primary gas pressure switch in the manifold activates the gear motor that controls the bypass damper in the venter/combustion air system. The bypass damper opens diverting some of the incoming air directly into the flue duct, reducing airflow through the burner. Safety switches monitor the position of the bypass damper. When the gas pressure increases above 1.1" w.c., the bypass damper closes.

Combustion Air Pressure Switch Settings for Model SCE with Option AG39 or AG40

Sensor Location

This uniquely designed modulation system requires combustion air pressure settings different from the standard system. The approximate settings for the combustion air proving switch at sea-level operation are:

For the convenience of the installer, the duct temperature sensor is factory installed in the cabinet leg (See FIGURE 23, page 25). Although the sensor has a mixing tube, at this distance from the discharge it does not receive a true mix, so the temperature read by the sensor will be slightly higher than the actual air entering the ductwork. The system will provide comfort level heat if the selector is set slightly higher to compensate for this reading. If a direct correlation of these two temperatures is required, move the duct sensor to a location in the ductwork about 10-12 feet (3-

3.7 M) from the furnace discharge.

Wiring and Service

For wiring, consult the wiring diagram attached to the furnace. All wires in the electrical box connecting the modulation controls must have a temperature rating of 150°C. This is a unique system which includes custom-built components and custom settings. If service is required, follow the general troubleshooting guide on page 35 and the special troubleshooting guide in FIGURE 28.

21D. Computer Controlled Electronic

Modulation between 20-28% and 100% Firing Rate (U.S. Patent 6,109,255), Option AG40 - not available

on Size 350; available with natural gas only

Sizes with Startup Equilibrium Factory

AG39&40 Cold at Full Rate Setting

125-225 -1.3"w.c.±0.2 -1.05"w.c.±0.1 -1.0"w.c.±0.02

250-300, 400 -1.2"w.c.±0.2 -0.95"w.c.±0.1

-.70"w.c.±0.05

With this option the furnace is equipped with a Maxitrol signal conditioner (see illustration in FIGURE 26) which accepts an input signal of either 4-20 milliamps or 0-10 volts from a customer-supplied control device such as a computer. With the dip switches on the conditioner in the "on" positions, the condi-

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 27

Page 28

21D. Computer

Controlled Electronic Modulation

tioner accepts a 4-20 milliamp signal. In the "off" positions, the conditioner accepts a 0-10V signal. The conditioner converts the signal to the 0 to 20 volt DC current required to control the modulating valve. The heater functions and is equipped in the same way as described in Paragraph 21C (Option AG39) except that with computer control the temperatures are selected through the software and there is no temperature selector or duct sensor.

(cont'd)

FIGURE 28 - Troubleshooting Guide for Checking Bypass Combustion Air Damper Safety Circuit on Model SCE with Option AG39 or AG40

General Instructions: For each step,

check to ensure that the wiring is not defective and that the wiring connections are secure.

Symptom - Part 1: Main burners are inoperative. Assumes that 24 volts is available between Terminal 2 and Terminal 7.

Check combustion

damper lower end switch

adjustment. Replace end

switch if necessary.

Is there 24 volts

between Terminal 2 on #1

Time Delay Relay and

Terminal 7?

Is there 24 volts

between Terminal 84 and

Terminal 7?

YES

Is the

damper open?

Is there voltage

between Terminal 87 and

Terminal 7?

YES

Place a jumper

across Terminal

86 and Terminal 7.

YES

Go to

Troubleshooting

Chart for heater.

Replace primary

manifold

pressure switch.

Is there voltage

between Terminal 88 and

Terminal 7?

YES

Is there voltage

between Terminal 4 on

ignition permissive relay and

Terminal 7?

YES

Replace #1 time

delay relay.

Check combustion

damper lower end switch

adjustment. If necessary,

NONO

replace end switch.

Replace ignition

permissive

relay.

Replace combustion

damper gear motor.

Did the

damper close?

YESNO

Replace motor

run time delay

relay.

Symptom - Part 2: Steady call for heat - burner cycles. Assumes that 24 volts is available between Terminals 11 and 7 and Terminals 2 and 7.

Measure manifold

pressure

during burner cycling.

When the

manifold pressure is

BELOW 1.0" w.c., is there a steady

voltage between Terminal 95

and Terminal 7?

YES

Replace secondary

manifold pressure

switch.

While the

burner is cycling, is

there a steady voltage

between Terminal 84 and

Terminal 2?

YES

Replace the

primary manifold

pressure switch.

ABOVE 1.5" w.c., is there a steady

When the

manifold pressure is

voltage between Terminal 95

and Terminal 7?

Replace secondary

manifold pressure

switch.

YES

Is there voltage

between Terminal 4 of the

ignition premissive relay and

Terminal 7?

Replace ignition

permissive

relay.

Form RZ-NA I-SCE, Page 28

Page 29

22. Pilot and Ignition Systems

Ignition System

Natural gas units are equipped with a spark ignited intermittent safety pilot system that shuts off the pilot gas flow between heat cycles. Propane units (or as an option on natural gas units) require a lockout device that stops the gas flow to the pilot if the pilot fails to light in 120 seconds. The lockout device requires manual set by interruption of the thermostat circuit. Refer to the wiring diagram supplied with the unit for pilot system identification and proper wiring. Pilot with lockout is Option AH3; spark pilot without lockout is Option AH2.

Ignition Controller

As part of the intermittent safety pilot systems, the ignition controller provides the high voltage spark to ignite the pilot gas and also acts as the flame safety device. After ignition of the pilot gas, the ignition controller electronically senses the pilot flame. A low voltage DC electrical signal is imposed on the separate metal probe in the pilot assembly. The metal probe is electrically insulated from ground. The pilot flame acts as a conduction path to ground completing the DC circuit and proving pilot flame. Proper operation of the electronic spark ignition system requires a minimum flame signal of .2 microamps DC as measured by a microampmeter. With pilot flame proven, the ignition controller energizes the main gas valve.

CAUTION: Due to high voltage on pilot spark wire and pilot electrode, do not touch when energized. See Hazard Levels, page 2.

Pilot

All pilots are vertical, target type with lint-free feature. Pilot flame should be approximately 1-1/4" in length. Pilot gas pressure should be the same as the supply line pressure. Pilot gas is supplied through the combination valve; the pilot gas flow is controlled by an adjustment screw located in the valve body. For maintenance, see Paragraphs 30 and 31.

23. Burners,

Orifices, and Carryover System

Burners

Individually formed steel burners capable of operating on either natural or propane gas are used in this heater. These burners have accurate, machine-formed ports to give controlled flame stability and operation without lifting or flashback. All burners are lightweight and factory mounted in an assembly which permits all of the burners to be removed as a unit for inspection or service.

Burner Carryover Systems

All natural gas burners (except when equipped with electronic modulation Option AG39 or AG40; see Paragraph 21) are equipped with two flash carryover systems, one on each end of the burner rack. (NOTE: A natural gas burner rack on furnaces manufactured prior to Series 6 had a gas lighter tube carryover and one flash carryover.)

All propane gas burners are equipped with one flash carryover and a regulated gas lighter tube system. The carryover lighter tube receives its gas supply through a regulator, simultaneously with the gas to the burner orifices.

During regular service, check the main burner ports, the carryover assemblies, and the orifices for cleanliness.

FIGURE 29A - Natural Gas Burner Rack (does not apply to furnaces with Option AG39 or AG40)

Pilot

Auxiliary Sensor

Flash Carryover

FIGURE 29B - Burner Rack With a Propane Gas Pilot

Pilot

Carryover Lighter Tube Carryover Regulator

Auxiliary Flame Probe

Propane Gas Pilot

Flash

Carryover

Burner Orifices

Natural Gas Pilot

Heaters are shipped with orifices of proper size and type for gas specified. NOTE: Natural gas units have a dual flash carryover system and do not require a carryover orifice.

Flash

Carryover

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 29

Page 30

23. Burner Orifices (cont'd)

Model SCE Size

Burner Orifices

Natural Gas

Propane Gas

Carryover Orifice

Propane Gas

Qty

Drill S ize

P/N

Drill S ize

P/N

Drill S ize

P/N

125 150 175 200 225 250 300 350 400

5 7 7 9 9 12121416

#42#44#42#43#42#44#42#42#42

84437 11833 84437 11828 84437 11833 84437 84437 84437

1.45 mm # 55 1.45 mm #55 1.45 mm # 55 1.45 mm 1.45 mm 1.45 mm 61652 11830 61652 11830 61652 11830 61652 61652 61652

#70#65#65#65#65#59#59#56#56

9870 9680 9680 9680 9680 10370 10370 9791 9791

24. Burner Air Shutters

DANGER: Failure to adjust air shutters according to directions could cause property damage, personal injury, and or death.

25. Check

Installation and Startup

Check the

installation prior to

startup

Air shutters are required on propane units, optional on natural units. A slotted screw on the end of the manifold bracket moves air shutters and adjusts all burners simultaneously (See FIGURE

30). Turning the screw clockwise opens the air shutter; counterclockwise closes shutter. After the furnace has been in operation for 15 minutes, close air shutter until the flame turns yellow. Open shutter until yellow disappears.

FIGURE 30 Propane Gas Burner Rack Showing Burner Air

Burner Air

Shutter

Adjustment

Screw

Shutter Adjustment Screw

 Verify suspension/mounting methods and clearances. See Paragraphs 5 and 6.  Verify that the bolts removed from the shipping clips were returned to the heater cabinet.

See Paragraph 4.

 Check duct connections. See Paragraph 8.  Check venting. See Paragraph 9. Be sure that flue discharge and combustion air openings

are free of obstructions.

 Be sure electrical entrance and gas supply pipe openings are sealed.  Be sure that all condensate drains are open. See Paragraph 7.

Electrical Checks:

 Be certain the electrical supply matches voltage rating of the furnace. (See rating plate.)  Check all field wiring against the wiring diagram. Be sure that wire gauges are as required

for the electrical load.

 Check that fuses or circuit breakers are in place and sized correctly.

Gas Supply Checks:

 Check piping for leaks and proper gas line pressure. Bleed gas lines of trapped air. See

Paragraph 10. a) Turn manual shutoff valve to off position. b) Turn gas supply on. c) Observe gas meter for movement, or d) Attach pressure gauge readable to .1" w.c. and after turning gas on for ten seconds,

turn gas supply off. No change in pressure should occur over a three-minute period.

e) If either c) or d) above indicate a leak, locate leak by brushing a soapy solution on

all fittings. Bubbles will appear at a leak. Repair and repeat tests.

Blower Checks:

 Check blower pulley and motor pulley to be sure they are secure to the shafts. Check belt

tension and alignment. See Paragraph 17.

 Check the rotation of the blower. See Paragraph 17.  Verify the removal of all shipping supports. See Paragraph 4.  Check damper linkage. See Paragraph 26.

Startup

Form RZ-NA I-SCE, Page 30

Close all panels tightly. Turn electric and gas supply on to the furnace. Adjust the thermo-

stat or ductstat so that a call for heat exists. Observe for complete sequencing of safety pilot and ignition.

Page 31

Operating Sequence

1. Set the thermostat switch at its lowest setting.

2. Turn on power.

3. Turn on the manual gas valves.

4. Set thermostat at desired setting.

5. Thermostat calls for heat (a) The venter motor is energized after 15-second (approximate) time delay. (b) Venter flow switches from N.C. to N. O. contacts, energizing the pilot gas valve

and spark gap to produce a pilot flame on each operating cycle. The sensing probe proves the presence of the pilot flame and energizes the safety switch portion of the control. The switch action de-energizes the spark gap and energizes the main valve. The main gas ignites and the unit fires at full rate.

the main valve and recycles the spark gap. On unit equipped with a G770NGC-4 controller which includes lockout control, if the pilot is not established within 120 seconds (approximately), the unit locks out and must be reset by interrupting the power to the control circuit (See Lighting Instructions).

6. Blower motor operates from fan time delay.

7. Thermostat is satisfied. (a) Solenoid gas valve de-energized. (b) Pilot gas valve de-energized. (c) Ignition controller de-energized. (d) Time delay relay keeps venter motor on for approximately one minute (post purge).

8. To shut down, set thermostat to lowest setting. Blower motor remains on as determined by

fan time delay.

Check installation

after startup:

Observe burner flame at full fire. Natural gas flame should be about 1-1/2" in height with blue

coloring. Propane gas flame should be approximately the same length with blue coloring. Yellow tipping may appear on propane gas. If yellow extends beyond 1/2 to 3/4", adjust air shutters. See Paragraph 24. If shutter adjustment will not reduce yellowing, check for gas leaks at the control manifold or orifice fitting.

 Turn the unit off and on, pausing two minutes between each cycle. Observe for smooth

ignition. On two-stage or modulating burner systems, manipulate temperature adjustment slowly up and down to see if control is sequencing or modulating properly. Raising temperature setting drives burner on or to full fire.

 Using a manometer or slant gauge readable up to 14" w.c., check orifice manifold for

operating pressure on full fire. Natural gas should be 3.5" w.c. at this point. Propane gas should be 10" w.c. at this point. Variations from these pressures are not recommended, as ignition and efficiency performance can be adversely affected by improper pressure adjustment. See Paragraph 10.

 If the system is equipped with an optional dirty filter switch, set the switch. Follow the

instructions in Paragraph 27A.

 Place "Owner's Envelope" containing Limited Warranty Card, this booklet, and any optional

information in an accessible location near the heater. Follow the instructions on the envelope.

DANGER: The gas burner in this gas-fired equipment is designed and equipped to provide safe, controlled complete combustion. However, if the installation does not permit the burner to receive the proper supply of combustion air, complete combustion may not occur. The result is incomplete combustion which produces carbon monoxide, a poisonous gas that can cause death. Safe operation of separated-combustion, indirectfired gas burning equipment requires a sealed, properly operating vent system which vents all flue products to the outside atmosphere. FAILURE TO PROVIDE PROPER VENTING WILL RESULT IN A HEALTH HAZARD WHICH COULD CAUSE SERIOUS PERSONAL INJURY OR DEATH. Install either the horizontal or vertical combustion air/vent system illustrated in Paragraph 9 using the concentric adapter supplied. Always comply with the combustion air requirements in the installation codes and instructions. Combustion air at the burner should be regulated only by manufacturer-provided equipment. NEVER RESTRICT OR OTHERWISE ALTER THE SUPPLY OF COMBUSTION AIR TO ANY HEATER. CHECK THE COMBUSTION AIR/VENT SYSTEM FOR SOUNDNESS AND FUNCTION; MAINTAIN IT IN PROPER OPERATING CONDITION.

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 31

Page 32

OPTIONAL EQUIPMENT

26. Optional Dampers and Controls (See Wiring Diagram supplied with unit)

FIGURE 31 - Control Locations for Air Inlet/Damper Options

Outside Air

amper CLOSED

NOTE: The illustration is intended to show location only of various air control accessories and does not represent suggested combinations of accessories.

(1) Outside Air Damper (2) Return Air Damper (3) Damper Motor (4) Potentiometer

27. Optional Filter Rack and Filters

(5) Potentiometer (6) Mixed Air Controller (7) Warmup Control (8) Remote Potentiometer

Filter racks and filters are factory installed optional equipment on indoor systems. 1" or 2" disposable, pleated disposable, or permanent filters are available.

Heater Filters Metal Fillers FIGU RE Referen ce for

Filter

and Filler Sizes

150, 175 20x25 20x25 -- -- -- 13/16 13/16 200, 225 16x25 16x20 16x25 16x20 -- -- -250, 300 20x25 20x20 20x25 20x20 -- -- -- 32B

Outside

Air

Damper

Arm

Damper Linkage -When units are equipped with dampers, the dampers are closed during shipment. When there are both return air and outside air dampers,

the return damper linkage must be adjusted prior to use.

Rod for Outside Air Damper

Damper Motor

Rod for Return Air Damper

Set Screw

Return Air Damper Arm

Return Air Damper OPEN

1. Loosen the set screw on the return air damper rod at the damper arm.

2. Manually open the return air dampers. While the dampers are open-

ing, the damper rod and arm will automatically move to their correct positions.

3. Tighten the set screw.

Size A B C D E F1 F2 Qty of Filters and Fillers

125 20x20 20x20 -- -- -- -- -- 32A

350 20x25 20x25 20x25 20x20 -- 4-13/16 -400 16x25 20x25 16x25 20x25 16x25 2-5/8 1-1/16 32C

FIGURE 32A - Filter Arrangement Sizes 125175

27A. Optional Dirty Filter

Switch

Form RZ-NA I-SCE, Page 32

FIGURE 32B - Filter Arrangement

Sizes 200-350

FIGURE 32C - Filter Arrangement Size 400

The optional dirty filter pressure switch is used to provide warning to the user by energizing an indicator light on an optional remote console. The light indicates that the filters are in need of cleaning or changing. The adjustable, single-pole/normally open differential switch closes when an increase in pressure differential above the setpoint, is sensed across the filter bank. This switch is located in the furnace section. After the unit is started, before continuous operation, the dirty filter switch must be set.

Page 33

Instructions for Setting Dirty Filter Switch

With clean filters in place, blower doors closed, and blower in operation, decrease the pressure setting by adjusting the set screw on the switch clockwise until the filter light is energized or the screw is bottomed out. At that point, adjust the set screw three full turns counterclockwise or until the screw is top-ended. At that setpoint the filter light will be activated at approximately 50% filter blockage.

FIGURE 33 - Dirty Filter Switch

Negative pressure connection is toward the

"back or bottom" of the switch (senses

blower side of filters)

SERVICE AND MAINTENANCE

This unit will operate with a minimum of maintenance. To ensure long life and satisfactory performance, a furnace that is operating under normal conditions should be inspected every four months. If the furnace is operating in an area where an unusual amount of dust or soot or other impurities are present in the air, more frequent inspection is recommended.

WARNING: If you turn off the power supply, turn off the gas. See Hazard Levels, page 2.

NOTE: Use only factory-authorized replacement parts.

28. Operating Gas Valve

WARNING: The operating valve is the prime safety shutoff. All gas supply lines must be free of dirt or scale before connecting to the unit to ensure positive closure. See Hazard Levels, page 2.

Remove external dirt accumulation and check wiring connections.

The combination gas valve must be checked annually to ensure that the valve is shutting off gas flow completely.

Instructions:

1) Locate the 1/8” FPT INLET pressure tap on the combination valve (See FIGURE 34).

FIGURE 34 - Connect manometer to inlet pressure tap to check gas flow shutoff.

Single-Stage Valve

Pressure Tap

1/8" INLET

Set screw (on front of switch) must be manually adjusted after the system is in operation.

Positive pressure connection is toward the "front or top" of the switch (senses air inlet side of filters)

1/8” Outlet Pressure Tap

Two-Stage Valve

1/8” Outlet

1/8" INLET

Pressure Tap

2) With the manual valve turned off to prevent flow to the gas valve, connect a manometer to the 1/8” inlet pressure tap in the

valve. NOTE: A manometer (fluid-filled gauge) with an inches water column scale is recommended.

3) With the field-installed manual valve remaining closed, observe the manometer for two to three minutes for an indication of gas

pressure. No pressure should be indicated on the manometer. If the manometer indicates a gas pressure, the field-installed manual gas valve must be replaced or repaired before the combination gas valve can be checked.

4) If the manometer does not indicate gas pressure, slowly open the field-installed manual gas valve. After the manometer's

indicated gas pressure has reached equilibrium, close the manual shutoff valve. Observe the gas pressure. There should be no loss of gas pressure on the manometer. If the manometer indicates a loss of pressure, replace the combination gas valve before placing the heater in operation.

NOTE: Operational pressure settings and instructions for checking pressure settings are in Paragraph 10.

Pressure Tap

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 33

Page 34

29. Vent/Combustion Air System

Check at least once a year. Inspect all joints, seams and terminal caps. Replace any defective parts.

30. Burner Rack

Burner Rack Removal Instructions

1. Turn off the gas supply.

2. Turn off the electric supply.

3. Remove control access side panel.

4. Disconnect ignition and flame sensor leads.

5. Mark and disconnect electric valve leads.

6. Uncouple the union in the gas supply.

7. Remove sheetmetal screws in the top corners of the burner rack assembly.

8. Pull "drawer-type" burner rack out of the furnace.

To disassemble the burner rack:

1. Remove Carryover System -Natural Gas - remove the flash carryover system from the "manifold end" of the burner rack NOTE: Natural gas burner racks manufactured prior to Series 6 may have a lighter tube carryover system. Break the lighter tube connection at the orifice and remove the supply tubing, the drip shield and the lighter tube. Propane Gas - break the lighter tube connection at the regulator and remove the lighter tube orifice supply tubing; remove the retaining screws in the drip shield and the shield; remove the retaining screws and slide out the lighter tube.

2. Pull main burners horizontally away from injection opening and lift out.

3. Remove manifold bracket screws and remove manifold.

4. Remove burner orifices.

5. Remove screws and lift out pilot burner.

Follow the instructions in Paragraph 30 to clean. To re-assemble and replace, reverse the above procedures being careful not to create any unsafe conditions.

31. Cleaning Pilot and Burners

CAUTION: When cleaning, wearing eye protection is recommended.

32. Spark Ignition

System

CAUTION: Due to high voltage on pilot spark wire and pilot electrode, do not touch when energized. See Hazard Levels, page 2.

In the event the pilot flame is short and/or yellow, check the pilot orifice for blockage caused by lint or dust accumulation. Remove the pilot orifice and clean with air pressure. DO NOT REAM THE ORIFICE. Check and clean the aeration slot in the pilot burner. Clean the metal sensing probe and the pilot hood with an emery cloth and wipe off the ceramic insulator. Check the spark gap; spark gap should be maintained to .100". After the pilot is cleaned, blow any dirt away with compressed air.

Clean main burners and burner orifices using air pressure. Use an air nozzle to blow out scale and dust accumulation from the burner ports. Alternately blow through the burner ports and the venturi. Use a fine wire to dislodge any stubborn particles from the burner ports. Do not use anything that might change the port size.

Clean the burner rack carryover systems with air pressure.

The ignition controller provides the high voltage spark to ignite the pilot service and also acts as the flame safety device. After ignition of the pilot gas, the controller electronically senses the pilot flame. A separate solid metal probe in the pilot burner assembly is used to sense the flame. A low voltage DC electrical signal is imposed on the metal probe which is electrically insulated from ground. Proper operation of the electronic spark ignition system requires a minimum flame signal of .2 microamps DC as measured by a microampmeter. When the pilot flame impinges on the sensing probe, the flame acts as a conduction path to ground. This completes the DC circuit; the ignition controller responds by energizing the main gas valve.

If no spark occurs, check the following: a) Voltage between blue and white terminals (non-lockout type pilot) and Terminals 2 and 5

(lockout type pilot) on the ignition controller should be at least 20 volts and no higher than

32 volts. Refer to Troubleshooting (Paragraph 36) if no voltage is observed. b) Short to ground in the high tension lead and/or ceramic insulator. c) Pilot spark gap should be approximately .100". (See FIGURE 35.)

NOTE: When checking for spark with the pilot burner assembly removed from the burner rack, the pilot assembly must be grounded to the heater for proper spark. If the above conditions are normal and no spark occurs, replace the ignition controller.

Form RZ-NA I-SCE, Page 34

Page 35

FIGURE 35 - Pilot Assembly Spark Gap

Top View

Side View

If the main gas valve fails to open with a normal full size pilot flame established, check for the following:

a) If voltage between black and brown leads on the main gas valve is 20 to 32 VAC and there is

no main gas flow with the built-in manual valve in FULL OPEN position, the main valve is defective.

b) If there is no voltage between black and brown leads on the main gas valve, check for

disconnected or shorted flame sensor lead or flame sensor probe. When the above conditions are normal and the main gas flow is still off, the ignition controller is probably defective. Do not attempt to service the ignition controller; it does not contain any replaceable components.

33. Cleaning the Heat Exchanger

34. Venter Motor

35. Air Circulation

System

36. Limit Control Check

37. Troubleshooting

To clean the inner surfaces of the heat exchanger, remove the burner rack assembly (See Paragraph 29.) permitting access to the inside of the heat exchanger tubes.

Clean the tubes using a 1/2" diameter furnace brush. A mirror and flashlight are helpful in examining the narrow section of each tube. Remove any accumulated dust and soot.

Power venter motors are permanently lubricated. No oiling is required.

Check blower pulley and motor pulley to be sure they are secured to the shaft. Check belt condition and belt tension (See Paragraph 17).

With the heater on, completely block off the distribution air. The limit control should open within a few minutes, shutting off gas supply to the main burners.

Reference: If the furnace is equipped with electronic modulation Option AG39 or AG40, consult the troubleshooting chart, FIGURE 28, page 28.

TROUBLE P RO BAB LE CAUS E REMED Y Venter motor will not start

Pilot will not li ght -Venter operating

No pow er to the furnace.

No 24-volt power to venter relay.

Venter relay defective.

Defective motor or capacitor.

Manual valve not open.

Air in gas line.

Dirt in p ilot orifice.

Gas p ressure too high or too low.

Kinked pilot tubing.

Pilot valve does not open.

No sp ark:

Loose wire connections

Trans former failure.

Incorrect s park gap.

Spark cable shorted to ground.

Spark electrode shorted to ground.

Draf ts affecting p ilot.

Ignition control not grounded.

Faulty ignit ion controller.

Optional lockout device interrupting control circuit by

above causes.

Faulty combustion air proving swit ch.

Turn on p ower, check supp ly fuses or circuit breaker.

Turn up thermost at, check cont rol transformer out put. Ch eck for loose or

improp er wire connectio ns.

Rep lace.

Rep lace defect ive p art.

Op en manual valve.

Bleed gas line.

Remove and clean with comp ressed air or s olvent .

Adjust sup ply pressure. (See Paragraph 10).

Replace t ubing.

If 24 volt is available at t he valve, replace valve.

Be cert ain all wires connect ions are solid.

Be cert ain 24 volts is available.

Maintain sp ark gap at .100".

Rep lace worn or grounded sp ark cable.

Rep lace pilot if ceramic sp ark elect rode is cracked or grounded.

M ake su re all p anels are in place and tight ly secured to p revent draft s at pilot.

M ake cert ain ignition cont rol is grounded to furnace chas sis.

If 24 volt is available to t he ignition cont roller and all ot her caus es have been

eliminat ed, rep lace ignit ion con trol.

Reset lockout by interrupt ing control at thermostat.

Rep lace combustion air p roving switch .

(continued on page 36)

Form RZ-NA I-SCE, Mfg #207697 Rev 4, Page 35

Page 36

CQS

37. Troubleshooting (cont'd)

prop

pping

prop

Installation Record

www.RezSpec.com; (800) 695-1901 ©2013 Thomas & Betts Corporation, All rights reserved. Trademark Notes: Reznor® is registered in at least the United States. All other trademarks are the property of their respective owners. 07/13 Form I-SCE Version A.3

TROUBLE (cont'd) PROBABLE CAUSE (cont'd) REMEDY (cont'd) Pilot lights, main valve will not open

No heat (Heater operating)

Motor will not run

Motor turns on and off while operating

Motor cuts out on ove rload

Manual valve not open.

M ain valve not operating.

Defective valve.

Loose wire connections.

Ignition control does not power main valve.

Loose wire connections.

Flame s ensor grounded. (Pilot light s - spark

continues)

Gas pressure incorrect.

Cracked ceramic at s ensor.

Faulty ignition controller.

filters in blower system.

Dirt

Incorrect manifold

cling on limit control.

er t hermostat locatio n or adjustment.

Im Belt sli Fan control im Defective fan cont rol.

Blower set for too low tem Circuit op en

Fan Control inoperative

Fan control imp roperly wired

Contactor inop erative

Defective motor.

M otor overload device cy cling

3-phase motor rotating in opposite direction

Improper motor pulley adjustment Improper st atic pressure on duct system Low voltage

ressure or orifices.

on blower

erly wired

erat ure rise.

Op en manual valve.

If 24 volt is measured at valve connections and valve remains closed, replace

valve.

Check and tight en all wiring con nections.

Be cert ain flame s ensor lead is not grounded or insulat ion or ceramic is not

cracked. Rep lace as required.

Adjust gas pres sure. (See Paragrap h 10.)

Rep lace sens or.

See Paragrap h 31. If all checks indicate no other cause, rep lace ignition

cont roller. field replaceable parts.

Do not

Clean or replace filt ers. Check manifold pressure (See Paragraph 10).

Check air throughput.

See thermost at manufactu rer's instructions.

Adjust belt tension

Connect as per wiring diagram.

lace fan control.

Slow down blower or increase stat ic pressure.

Check wiring and connections. Rep lace fan contro l.

Connect as p er wiring diagram.

Rep lace cont actor.

Rep lace motor.

Check motor load against motor rating p lace. Rep lace motor or overload device.

Interchange two legs of sup ply connections.

See inst ruct ions on air throughp ut (See P aragraph 17). Adjust dampers in duct sy stem. Check power supply.

attempt to repair the ignition controller. This device has no

FIRST: Contact the installer.

Name _______________________________________________________________________________________

Address ________________________________________________________________________________________

________________________________________________________________________________________

Phone ________________________________________________________________________________________

SECOND: Contact the nearest distributor (See Yellow Pages). If no listing,

contact Authorized Factory Representative, 1-800-695-1901 (Press 1).

THIRD: Contact: REZNOR

150 McKinley Avenue

Mercer, PA 16137

Phone: (724) 662-4400

Model No. ____________________________________________________

Unit Serial No. ________________________________________________

Date of Installation _____________________________________________

/Thomas & Betts Corporation

Thomas & Betts Reznor SCE Installation Operation & Maintenance

Specifications and Main Features

Frequently Asked Questions

User Manual