FOR UPFLOW/HORIZONTAL TWO STAGE, COMMUNICATING
GAS FURNACES W/ECM BLOWER
(-)802V UPFLOW/HORIZONTAL SERIES
(-)(-)80MDV UPFLOW/HORIZONTAL SERIES
U.L. and/or C.S.A. recognized fuel gas and CO (carbon monoxide) detectors are recommended in all applications, and their installation should be in accordance with the
manufacturer’s recommendations and/or local laws, rules, regulations, or customs.
IMPORTANT: TO INSURE PROPER INSTALLATION AND OPERATION OF THIS PRODUCT, COMPLETELY READ ALL INSTRUCTIONS PRIOR TO ATTEMPTING TO ASSEMBLE, INSTALL, OPERATE, MAINTAIN OR REPAIR THIS PRODUCT. UPON UNPACKING
OF THE FURNACE, INSPECT ALL PARTS FOR DAMAGE PRIOR TO INSTALLATION AND START-UP.
Page 3
3
General Information
GENERAL INFORMATION
NOTE: A heat loss calculation should be performed to properly
determine the required furnace BTU size for the structure. Also,
the duct must be properly designed and installed for proper airflow. Existing ductwork must be inspected for proper size and to
make sure that it is properly sealed. Proper airflow is necessary
for both user comfort and equipment performance.
Before opening the furnace carton, verify that the data tags on
the carton specify the furnace model number that was ordered
from the distributor and are correct for the installation. If not,
return the unit without opening the carton. If the model number
is correct, open the carton and verify that the furnace rating
label specifies the same furnace model number that is specified on the carton label. If the model numbers do not match, return the furnace to the distributor.
IMPORTANT: Proper application, installation and maintenance of
this furnace and system is a must if consumers are to receive the full
benefits for which they have paid.
The (-)802V/(-)(-)MDV series furnaces are design certified by CSA
for use with natural and propane gases as follows:
As a Category I furnace, it may be vented vertically with type B1 vent pipe and also may be common vented as described in
these instructions.
This furnace should be installed in accordance with the American
National Standard Z223.1 - latest edition booklet entitled “National
Fuel Gas Code” (NFPA 54), and the requirements or codes of the
local utility or other authority having jurisdiction including local
plumbing or waste water codes.
With the introduction of higher efficiency furnaces, special attention
must be paid to the venting system. Only listed venting systems
may be used as stated in the installation instructions and the
Na-
tional Fuel Gas Code, ANSI Z223.1 (NFPA 54),.
Since furnace
technology and venting requirements are changing, awareness of
local, state, and federal codes and industry changes is imperative.
ST-A1220-30
FIGURE 1
FURNACE COMPONENTS
15
16
17
18
19
20
21
1
2
3
14
13
1.) DOOR SWITCH
2.) TRANSFORMER
3.) JUNCTION BOX
12
4.) LOW VOLTAGE TERMINAL
5.)HEAT ASSISTED LIMIT CONTROL (HALC)
6.) SOLID METAL BASE PAN
7.) FURNACE CONTROL
11
8.) CONTROL MOUNTING PLATE
9.) BLOWER
10.) POWER FACTOR CORRECTION CHOKE (PFC)
(EXCEPT 50kBTU AND 75kBTU-17”)
11.) IGNITER
12.) GAS VALVE
13.) INDUCED DRAFT BLOWER
14.) 4” FLUE ADAPTER (OPTIONAL)
15.) COMBUSTION AIR INLET
16.) MAIN LIMIT
10
17.) COMBUSTION AIR DIFFUSER
18.) PRESSURE SWITCHES,
HIGH AND LOW STAGE
9
19.) OVER TEMPERATURE SWITCH
20.) BURNER
21.) FLAME SENSOR
8
4
5
6
7
Page 4
4
Install this furnace in accordance with the American National Standard Z223.1 – latest edition entitled “National Fuel Gas Code”
(NFPA54) or codes of the local utilities or other authorities having
jurisdiction. This is available from the following:
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
CSA-INTERNATIONAL
5060 Spectrum Way
Mississauga, Ontario
Canada L4W5N6
Online: www.csa.ca
RECEIVING
Immediately upon receipt, all cartons and contents should be inspected for transit damage. Units with damaged cartons should
be opened immediately. If damage is found, it should be noted on
the delivery papers, and a damage claim filed with the last carrier.
• After unit has been delivered to job site, remove carton taking
care not to damage unit.
• Check the unit rating plate for unit size, electric heat, coil, voltage, phase, etc. to be sure equipment matches what is required for the job specification.
• Read the entire instructions before starting the installation.
• Some building codes require extra cabinet insulation and gasketing when unit is installed in attic applications.
• If installed in an unconditioned space, apply caulking around
the power wires, control wires, refrigerant tubing and condensate line where they enter the cabinet. Seal the power wires on
the inside where they exit conduit opening. Caulking is required to prevent air leakage into and condensate from forming
inside the unit, control box, and on electrical controls.
• Install the unit in such a way as to allow necessary access to
the coil/filter rack and blower/control compartment.
• Install the unit in accordance with any local code which may
apply and the national codes. Latest editions are available
from: “National Fire Protection Association, Inc., Batterymarch
Park, Quincy, MA 02269.” These publications are:
• ANSI/NFPA No. 70-(Latest Edition) National Electrical Code.
• NFPA90A Installation of Air Conditioning and Ventilating Systems.
• NFPA90B Installation of warm air heating and air conditioning
systems.
• The equipment has been evaluated in accordance with the
Code of Federal Regulations, Chapter XX, Part 3280.
CALIFORNIA RESIDENTS ONLY
IMPORTANT: All manufacturer products meet current Federal
OSHA Guidelines for safety. California Proposition 65 warnings
are required for certain products, which are not covered by the
OSHA standards.
California's Proposition 65 requires warnings for products sold in
California that contain, or produce, any of over 600 listed chemicals known to the State of California to cause cancer or birth defects such as fiberglass insulation, lead in brass, and combustion
products from natural gas.
All “new equipment” shipped for sale in California will have labels
stating that the product contains and/or produces Proposition 65
chemicals. Although we have not changed our processes, having
the same label on all our products facilitates manufacturing and
shipping. We cannot always know “when, or if” products will be
sold in the California market.
You may receive inquiries from customers about chemicals found
in, or produced by, some of our heating and air-conditioning equipment, or found in natural gas used with some of our products.
Listed below are those chemicals and substances commonly associated with similar equipment in our industry and other manufacturers.
• Glass Wool (Fiberglass) Insulation
• Carbon Monoxide (CO)
• Formaldehyde
• Benzene
More details are available at the Websites for OSHA (Occupational Safety and Health Administration), at www.osha.gov
and the
State of California's OEHHA (Office of Environmental Health Hazard Assessment), at www.oehha.org.
Consumer education is important since the chemicals and substances on the list are found
in our daily lives. Most consumers are aware that products present safety and health risks, when improperly used, handled and
maintained.
______ Correct clearance to combustibles (record clearance)
______ Correct clearance for service (at front) (record clearance)
DUCT STATIC PRESSURE
______ in. w.c. on heating speed (record static pressure)
______ in. w.c. on cooling speed (record static pressure)
______ Air temperature rise in heat (record air temperature rise)
______ Air temperature rise in cool (record air temperature rise)
VENTING
______ Correct vent pipe diameter and length (according to NFGC tables) _________________ Vent connection size
______ Correct venting material (according to NFGC tables)
______ Correct lining for masonry chimneys
______ Adequate clearance from combustibles
______ Proper negative pressure reading in the vent
______ Vent pipe secured to induced draft blower housing
COMBUSTION AIR
______ Proper source of combustion air
______ Correct combustion air opening size
______ Optional attic combustion air pull
______ Non-attic combustion air pull
Checklist
Installation Instructions remain with the furnace as a reference guide to the servicing contractor. We recommend
that performance and installation data be recorded for future reference on this sheet to meet service and warranty
obligations so that job site information is available when required.
Page 6
Safety Information
SAFETY INFORMATION
!
WARNING
IN COMPLIANCE WITH RECOGNIZED CODES, IT IS RECOMMENDED THAT AN AUXILIARY DRAIN PAN BE INSTALLED UNDER THIS FURNACE AND ANY INSTALLED
EVAPORATOR COIL THAT IS LOCATED IN ANY AREA OF
A STRUCTURE WHERE DAMAGE TO THE BUILDING OR
BUILDING CONTENTS MAY OCCUR AS A RESULT OF AN
OVERFLOW OF THE A/C COIL DRAIN PAN.
!
WARNING
DO NOT INSTALL THIS FURNACE IN A MOBILE HOME!!
THIS FURNACE IS NOT APPROVED FOR INSTALLATION
IN A MOBILE HOME. DOING SO COULD CAUSE FIRE,
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
!
WARNING
INSTALL THIS FURNACE ONLY IN A LOCATION AND POSITION AS SPECIFIED IN THE LOCATION REQUIREMENTS AND CONSIDERATIONS SECTION OF THESE
INSTRUCTIONS.
!
WARNING
IMPROPER INSTALLATION, OR INSTALLATION NOT
MADE IN ACCORDANCE WITH THE CSA INTERNATIONAL
(CSA) CERTIFICATION OR THESE INSTRUCTIONS, CAN
RESULT IN UNSATISFACTORY OPERATION AND/OR DANGEROUS CONDITIONS AND ARE NOT COVERED BY THE
MANUFACTURER’S WARRANTY.
!
WARNING
DO NOT BYPASS, JUMPER, OR REMOVE ANY SAFETY
SWITCH FROM THE FURNACE CONTROL CIRCUIT. IF A
SAFETY SWITCH CAUSES THE FURNACE TO SHUT
DOWN OR OPERATE INTERMITTENTLY, IT IS AN INDICATION OF A POTENTIAL SAFETY HAZARD THAT MUST BE
ADDRESSED BY A QUALIFIED TECHNICIAN, SERVICE
AGENCY OR THE GAS SUPPLIER. DO NOT RESET
SAFETY CONTROLS WITHOUT CORRECTIVE ACTION
AND/OR VERIFICATION OF PROPER SAFE OPERATION
BY A QUALIFIED INSTALLER, SERVICE AGENCY OR THE
GAS SUPPLIER.
REPLACE ANY SAFETY CONTROL COMPONENT ONLY
WITH IDENTICAL OEM REPLACEMENT PARTS. WHEN A
NEW SAFETY SWITCH IS INSTALLED, IT MUST BE
TESTED FOR A MINIMUM OF 15 MINUTES WITH THE
FURNACE OPERATING AT MAXIMUM INPUT RATE AND
WITH BOTH BLOWER AND BURNER DOOR INSTALLED.
IF THE FURNACE IS INSTALLED IN A CLOSET, THE
CLOSET DOOR MUST ALSO BE CLOSED FOR THIS
TEST. REPEAT THE TEST AT THE MINIMUM INPUT RATE
IF THE FURNACE IS A MULTI-STAGE FURNACE.
!
WARNING
USE ONLY WITH THE TYPE OF GAS APPROVED FOR
THIS FURNACE. REFER TO THE FURNACE RATING
PLATE.
!
WARNING
NEVER TEST FOR GAS LEAKS WITH AN OPEN FLAME.
USE A COMMERCIALLY AVAILABLE SOAP SOLUTION
MADE SPECIFICALLY FOR THE DETECTION OF LEAKS
TO CHECK ALL CONNECTIONS, AS SPECIFIED IN GAS
SUPPLY AND PIPING SECTION OF THESE INSTRUCTIONS.
!
WARNING
COMBUSTION AND VENTILATION AIR MUST BE PROVIDED TO THE FURNACE AS REQUIRED BY THE NATIONAL FUEL-GAS CODE (U.S.) AND THE COMBUSTION
AND VENTILATION AIR SECTION OF THESE INSTRUCTIONS.
!
WARNING
COMBUSTION PRODUCTS MUST BE DISCHARGED OUTDOORS. CONNECT THIS FURNACE TO AN APPROVED
VENT SYSTEM ONLY, AS SPECIFIED IN THE VENT PIPE
INSTALLATION SECTION OF THESE INSTRUCTIONS.
!
WARNING
WHEN A FURNACE IS INSTALLED SO THAT SUPPLY
DUCTS CARRY AIR CIRCULATED BY THE FURNACE TO
AREAS OUTSIDE THE SPACE CONTAINING THE FURNACE, THE RETURN AIR SHALL ALSO BE HANDLED BY
DUCT(S) SEALED TO THE FURNACE CASING AND TERMINATING OUTSIDE THE SPACE CONTAINING THE FURNACE.
!
WARNING
WHENEVER THE FACTORY RETURN-AIR CONNECTION
IS NOT USED IT MUST BE SEALED. A SOLID METAL
BASE PLATE MUST BE INSTALLED AND SEALED. FACTORY BASE PLATES ARE AVAILABLE AS ACCESSORY
ITEMS. (PART NUMBERS ARE LISTED IN THE SPEC
SHEET FOR THE FURNACE.) FAILURE TO INSTALL AND
SEAL THE BASE PLATE AND RETURN AIR DUCT CONNECTIONS MAY ALLOW CARBON MONOXIDE AND
OTHER CONTAMINANTS TO BE DRAWN INTO THE CONDITIONED AIR SPACE AND DISTRIBUTED THROUGHOUT
THE HEATED SPACE.
!
WARNING
DO NOT OPERATE THE SYSTEM WITHOUT FILTERS. A
PORTION OF THE DUST ENTRAINED IN THE AIR MAY
TEMPORARILY LODGE IN THE AIR DUCT RUNS AND AT
THE SUPPLY REGISTERS. ANY CIRCULATED DUST PARTICLES WILL BE HEATED AND CHARRED BY CONTACT
WITH THE FURNACE HEAT EXCHANGER. THIS SOOTY
RESIDUE WILL SOIL CEILINGS, WALLS, DRAPES, CARPETS AND OTHER HOUSEHOLD ARTICLES. SOOT DAMAGE MAY ALSO RESULT WITH, OR WITHOUT, FILTERS IN
PLACE, WHEN CERTAIN TYPES OF CANDLES ARE
BURNED, OR CANDLEWICKS ARE LEFT UNTRIMMED.
6
Page 7
7
SAFETY
Safety Information
IMPORTANT INFORMATION ABOUT
EFFICIENCY AND INDOOR AIR
QUALITY
Central cooling and heating equipment is only as efficient as the
duct system that carries the cooled or heated air. To maintain efficiency, comfort and good indoor air quality, it is important to have
the proper balance between the air being supplied to each room
and the air returning to the cooling and heating equipment.
Proper balance and sealing of the duct system improves the efficiency of the heating and air conditioning system and improves
the indoor air quality of the home by reducing the amount of airborne pollutants that enter homes from spaces where the ductwork and / or equipment is located. The manufacturer and the
U.S. Environmental Protection Agency’s Energy Star Program
recommend that central duct systems be checked by a qualified
contractor for proper balance and sealing.
FIGURE 2
MIGRATION OF DANGEROUS SUBSTANCES, FUMES, AND ODORS INTO
LIVING SPACES
Adapted from
Residential Duct Diagnostics and Repair
, with permission of Air Conditioning
Contractors of America (ACCA).
!
WARNING
DUCT LEAKS CAN CREATE AN UNBALANCED SYSTEM
AND DRAW POLLUTANTS SUCH AS DIRT, DUST, FUMES
AND ODORS INTO THE HOME CAUSING PROPERTY
DAMAGE. FUMES AND ODORS FROM TOXIC, VOLATILE
OR FLAMMABLE CHEMICALS, AS WELL AS AUTOMOBILE EXHAUST AND CARBON MONOXIDE (CO), CAN BE
DRAWN INTO THE LIVING SPACE THROUGH LEAKING
DUCTS AND UNBALANCED DUCT SYSTEMS CAUSING
PERSONAL INJURY OR DEATH (SEE FIGURE 2).
• IF AIR-MOVING EQUIPMENT OR DUCTWORK IS LOCATED IN GARAGES OR OFF-GARAGE STORAGE
AREAS - ALL JOINTS, SEAMS, AND OPENINGS IN THE
EQUIPMENT AND DUCT MUST BE SEALED TO LIMIT
THE MIGRATION OF TOXIC FUMES AND ODORS INCLUDING CARBON MONOXIDE FROM MIGRATING
INTO THE LIVING SPACE.
• IF AIR-MOVING EQUIPMENT OR DUCTWORK IS LOCATED IN SPACES CONTAINING FUEL BURNING APPLIANCES SUCH AS WATER HEATERS OR BOILERS ALL JOINTS, SEAMS, AND OPENINGS IN THE EQUIPMENT AND DUCT MUST ALSO BE SEALED TO PREVENT DEPRESSURIZATION OF THE SPACE AND
POSSIBLE MIGRATION OF COMBUSTION BYPRODUCTS INCLUDING CARBON MONOXIDE INTO THE LIVING SPACE.
!
WARNING
BLOWER AND BURNERS MUST NEVER BE OPERATED
WITHOUT THE BLOWER DOOR IN PLACE. THIS IS TO
PREVENT DRAWING GAS FUMES (WHICH COULD CONTAIN HAZARDOUS CARBON MONOXIDE) INTO THE
HOME THAT COULD RESULT IN PERSONAL INJURY OR
DEATH.
!
WARNING
ALWAYS INSTALL THE FURNACE TO OPERATE WITHIN
THE FURNACE’S INTENDED TEMPERATURE-RISE
RANGE WITH A DUCT SYSTEM WHICH HAS AN EXTERNAL STATIC PRESSURE WITHIN THE ALLOWABLE
RANGE, AS SPECIFIED IN THE DUCTING SECTION OF
THESE INSTRUCTIONS. SEE ALSO FURNACE RATING
PLATE.
INSTALLATION MUST COMPLY WITH ALL INSTALLATION
INSTRUCTIONS INCLUDING:
PROPER VENT INSTALLATION;
‐
FURNACE OPERATING UNDER THERMOSTAT‐
CONTROL;
RETURN AIR DUCT SEALED TO THE FURNACE;
‐
AIR FILTERS IN PLACE;‐
SET FURNACE INPUT RATE AND TEMPERATURE‐
RISE PER RATING PLATE MARKINGS;
MEANS FOR PROVIDING OUTDOOR AIR RE-
‐
QUIRED FOR COMBUSTION;
RETURN AIR TEMPERATURE MAINTAINED BE-
‐
TWEEN 55°F (13°C) AND 80°F (27°C); AND
CLEAN FURNACE, DUCT WORK AND COMPO-
‐
NENTS UPON SUBSTANTIAL COMPLETION OF
THE CONSTRUCTION PROCESS, AND VERIFY
THAT THE FURNACE OPERATING CONDITIONS
INCLUDING IGNITION, INPUT RATE, TEMPERATURE RISE AND VENTING, ACCORDING TO THE
INSTRUCTIONS AND CODES.
Page 8
8
1. IMPORTANT: If installing the unit over a finished ceiling or liv-
ing area, be certain to install an auxiliary condensate drain pan
under the entire unit. This auxiliary drain pan should extend
under any evaporator coil installed with the furnace.
2. IMPORTANT: If using a cooling evaporator coil with this fur-
nace, be sure the air passes over the heat exchanger before
passing over the cooling coil. The cooled air passing over the
warm ambient air inside the heat exchanger tubes can cause
condensation inside the tubes resulting in corrosion and eventual failure.
If there are manual dampers, they must be equipped to prevent
heating or cooling operation unless the damper is in the full heat
or cool position.
3. NOTE: This furnace is shipped with heat exchanger support
brackets installed under the back of the heat exchanger. These
may be removed before installation, but it is not required.
4. IMPORTANT:
This furnace is not approved or recommended
for installation on its back, with access doors facing upwards.
5. This furnace is suitable for installation in buildings constructed
on-site. This heating unit should be centralized with respect to
the heat distribution system as much as practicable.
6. NOTE: These furnaces are approved for installation in attics,
as well as alcoves, utility rooms, closets and crawlspaces.
7. IMPORTANT:
Support this unit when installed. For attic or crawl
space installation, horizontal furnaces may be installed on combustible wood flooring or by using support brackets. See Figure
3.
8. IMPORTANT:
If installing in a utility room, be sure the door is
wide enough to:
a. allow the largest part of the furnace to pass; or
b. allow any other appliance (such as a water heater) to pass.
SITE SELECTION
1. Select a site in the building near the center of the proposed, or existing, duct system.
2. Give consideration to the vent system piping when selecting the furnace location. Be sure the venting system
can get from the furnace to the termination with minimal
length and elbows.
3. Locate the furnace near the existing gas piping. Or, if
running a new gas line, locate the furnace to minimize
the length and elbows in the gas piping. See Figure 3.
4. Locate the furnace to maintain proper clearance to
combustibles as shown in following Figure 4.
CLEARANCE – ACCESSIBILITY
The design of forced air furnaces with input ratings as
listed in the tables under Figure 4 are certified by CSA-International for the clearances to combustible materials
shown in inches.
See name/rating plate and clearance label for specific
model number and clearance information.
Service clearance of at least 24 inches (30 cm) is recommended in front of all furnaces.
NOTE: Use recommended 24” (30 cm) clearance if accessibility clearances are greater than fire protection clearances.
ACCESSIBILITY CLEARANCES, WHERE GREATER, MUST
TAKE PRECEDENCE OVER FIRE PROTECTION CLEARANCES.
GENERAL INFORMATION
LOCATION REQUIREMENTS
Location
!
WARNING
WHEN THIS FURNACE IS INSTALLED IN A RESIDENTIAL
GARAGE, IT MUST BE INSTALLED SO THE BURNERS
AND IGNITION SOURCE ARE LOCATED NO LESS THAN
18 INCHES [450MM] ABOVE THE FLOOR. THIS IS TO PREVENT THE RISK OF IGNITING FLAMMABLE VAPORS
WHICH MAY BE PRESENT IN A GARAGE. ALSO, THE FURNACE MUST BE LOCATED OR PROTECTED TO AVOID
PHYSICAL DAMAGE BY VEHICLES. FAILURE TO FOLLOW
THESE WARNINGS CAN CAUSE A FIRE OR EXPLOSION,
RESULTING IN PROPERTY DAMAGE, PERSONAL INJURY
OR DEATH.
!
WARNING
THIS FURNACE IS NOT APPROVED OR RECOMMENDED
FOR INSTALLATION ON ITS BACK, WITH ACCESS DOORS
FACING UPWARDS.
!
WARNING
DO NOT LIFT THE UNIT BY THE HEAT EXCHANGER
TUBES. DOING SO CAN DAMAGE THE HEAT EXCHANGER ASSEMBLY.
Page 9
9
Location
GENERAL INFORMATION (cont.)
LOCATION REQUIREMENTS
ST-A1220-03
FIGURE 3
!
WARNING
COMBUSTIBLE MATERIAL MUST NOT BE PLACED ON
OR AGAINST THE FURNACE JACKET. THE AREA
AROUND THE FURNACE MUST BE KEPT CLEAR AND
FREE OF ALL COMBUSTIBLE MATERIALS INCLUDING
GASOLINE AND OTHER FLAMMABLE VAPORS AND LIQUIDS. PLACEMENT OF COMBUSTIBLE MATERIALS ON,
AGAINST OR AROUND THE FURNACE JACKET CAN
CAUSE AN EXPLOSION OR FIRE RESULTING IN PROPERTY DAMAGE, PERSONAL INJURY OR DEATH. THE
HOMEOWNER SHOULD BE CAUTIONED THAT THE FURNACE AREA MUST NOT BE USED AS A BROOM CLOSET
OR FOR ANY OTHER STORAGE PURPOSES.
!
WARNING
UPFLOW AND HORIZONTAL FURNACES ARE DESIGNCERTIFIED FOR INSTALLATION ON COMBUSTIBLE
FLOORS. NOTE, HOWEVER, THAT FURNACES MUST NOT
BE INSTALLED DIRECTLY ON CARPETING, TILE OR
OTHER COMBUSTIBLE MATERIAL OTHER THAN WOOD
FLOORING. INSTALLATION ON A COMBUSTIBLE MATERIAL CAN RESULT IN FIRE, CAUSING PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
NOTE:
HORIZONTAL LEFT ORIENTATION DEPICTED IN ILLUSTRATION.
HORIZONTAL RIGHT ORIENTATION IS SIMILAR IN INSTALLATION.
AIR FLOW
Page 10
10
BOTTOM
TOP
LEFT SIDEFRONTRIGHT SIDE
GAS
CONNECTION
ELECTRICAL CONNECTION
LINE VOLTAGE
ELECTRICAL CONNECTION
LOW VOLTAGE
OPTIONAL
GAS CONNECTION
OPTIONAL LOW
VOLTAGE WIRING
OPTIONAL LINE VOLTAGE
WIRING
A
I
R
F
L
O
W
RETURN
AIR
SUPPLY
AIR
HOT
MODELABCDEFRIGHT SIDEBACKTOPFRONTVENT
51413 27/3210 5/8༃11 1/21 7/804༄0136༅85 lbs.
717 1/216 11/3212 3/8༃152 1/203༄0136༅105 lbs.
102119 27/3214 1/8༃18 1/22 1/2000136༅120 lbs.
1224 1/223 11/3215 7/8༃222 1/2000136༅140 lbs.
1524 1/223 11/3215 7/8༃222 1/2000136༅150 lbs.
༃MAY REQUIRE 3" TO 4" OR 3" TO 5" ADAPTER.
4" ADAPTER INCLUDED WITH (-)801P UNITS.
༄MAY BE 0" WITH TYPE B VENT.
༅MAY BE 1" WITH TYPE B VENT.
LEFT SIDE
REDUCED CLEARANCE (IN.)
SHIP
WGTS.
FIGURE 4
UPFLOW/HORIZONTAL DIMENSIONS
Location
ST-A1220-04
REDUCED CLEARANCE (IN.)
Input A B C D E F
Left Right
Back Top Front Vent
Ship.
Side Side Wgts.
050 14 12
27
/32 10
5
/8 ➀ 11
1
/2 1
7
/8 0 4➁ 0 1 3 6➂ 85 lbs.
050 17
1
/2 16
11
/32 12
3
/8 ➀ 15 2
1
/2 0 3➁ 0 1 3 6➂ 105 lbs.
075 17
1
/2 16
11
/32 12
3
/8 ➀ 15 2
1
/2 0 3➁ 0 1 3 6➂ 105 lbs.
075 21 19
27
/32 14
1
/8 ➀ 18
1
/2 2
1
/2 0 0 0 1 3 6➂ 120 lbs.
100 21 19
27
/32 14
1
/8 ➀ 18
1
/2 2
1
/2 0 0 0 1 3 6➂ 120 lbs.
125 24
1
/2 23
11
/32 15
7
/8 ➀ 22 2
1
/2 0 0 0 1 3 6➂ 140 lbs.
150 24
1
/2 23
11
/32 15
7
/8 ➀ 22 2
1
/2 0 0 0 1 3 6➂ 150 lbs.
CLEARANCE TO COMBUSTIBLE MATERIAL (INCHES)
UPFLOW/HORIZONTAL MODELS
➀ May require 3” to 4” or 3” or 5” adapter.
4” adapter optional.
➁ May be 0” with type B vent.
➂ May be 1” with type B vent.
*See furnace spec sheet for model availability.
Page 11
11
Proper air flow is required for the correct operation of this
furnace. Restricted air flow can cause erratic operation and
can damage the heat exchanger. The duct system must
carry the correct amount of air for heating and cooling if
summer air conditioning is used.
IMPORTANT: When using outside air, design and adjust
the system to maintain a return air temperature ABOVE
55° F during the heating season.
NOTE: Return air grilles and warm air registers must not
be obstructed or closed.
UPFLOW INSTALLATIONS
1. Position the unit to minimize long runs of duct or runs
of duct with many turns and elbows.
2. For side return: Cut an opening in the side. The opening should be cut the full width and height of the
knockouts on the unit. See Figure 6.
3. If summer air conditioning is desired, position the indoor coil on the supply-air side of the unit. Ensure that
no air can bypass the coil.
4. Connect the furnace to the supply air plenum. See Figure 7.
5. Connect the return air ducting to the return-air opening
at the bottom and/or side of the unit. Make the connections air-tight to prevent the migration of toxic fumes
and odors including carbon monoxide from migrating
into the living space.
6. If a filter is installed near the furnace, be sure to have
adequate space for installation and removal of the unit
filter.
7. NOTE: Where the maximum airflow is 1800 CFM or
more, BOTH
sides or the bottom must be used for the
return air. Do not take return air from the back of the
unit.
NOTE: DO NOT take return air from furnace rooms,
garages or cold areas. Avoid return air from utility rooms,
kitchens, laundry rooms and bathrooms.
DUCTING
Ducting
!
WARNING
BLOWER AND BURNERS MUST NEVER BE OPERATED
WITHOUT THE BLOWER DOOR IN PLACE. THIS IS TO
PREVENT DRAWING GAS FUMES (WHICH COULD CONTAIN HAZARDOUS CARBON MONOXIDE) INTO THE
HOME THAT COULD RESULT IN PERSONAL INJURY OR
DEATH.
!
WARNING
UPFLOW FURNACE: THE SOLID METAL BASE
(SHIPPED WITH THE FURNACE) PLATE MUST BE INSTALLED IN THE FURNACE BOTTOM WHEN USING
SIDE AIR RETURN. FAILURE TO INSTALL A BASE
PLATE COULD CAUSE THE PRODUCTS OF COMBUSTION TO CIRCULATE INTO THE LIVING SPACE
AND CREATE POTENTIAL LY HAZARDOUS CONDITIONS, INCLUDING CARBON MONOXIDE POISONING OR DEATH. FOR BOTTOM RETURN, A SOLID
METAL BASE PAN MUST NOT BE INSTALLED. SEE
FIGURE 5.
!
WARNING
SOME HEATING AIRFLOW VALUES MAY BE
HIGHER THAN THOSE REQUIRED FOR COOLING.
BE SURE TO SIZE DUCT FOR THE MAXIMUM POSSIBLE AIRFLOW VALUE.
SIZE AIRFLOW DISTRIBUTION SYSTEM TO ACCEPTABLE INDUSTRY STANDARDS AND METHODS. TOTAL STATIC PRESSURE DROP OF THE AIR
DISTRIBUTION SYSTEM SHOULD NOT EXCEED .8
INCHES W.C. THIS WILL INCLUDE ANY AIR CONDITIONER COIL, AIR FILTRATION SYSTEM, ZONING
SYSTEM, DUCTWORK, ETC. REFER TO ADDED
EQUIPMENT TECHNICAL INFORMATION TO OBTAIN
PRESSURE DROP INFORMATION WHEN EQUIPMENT IS OPERATING AT RECOMMENDED HEATING OR COOLING CFMS.
Page 12
12
Ducting
DUCTING
FIGURE 5
FIGURE 6
FIGURE 7
ST-A1220-10
ST-A1220-11
ST-A1220-08
NOTE:
SOLID BASEPLATEPROVIDEDWITH (-)801PMODELSONLY.
WHEN SOLID BASE PLATE IS USED . TAPE
AROUND BOTTOM FLANGES OF CABINET
BEFORE THE UNIT IS INSTALLED.
SOLID BASE FLANGE
FITS UNDER
CABINET BOTTOM
LIFT UP, PULL OUT
1. REMOVE 2 SCREWS, LIFT BASE UP, SLIDE FORWARD TO REMOVE.
2. INSTALLATION IS REVERSE OF REMOVAL.
** VERIFY REAR FLANGE IS SEALED PROPERLY AS SHOWN IN DETAIL.
ST-A1220-10-X0
Page 13
13
HORIZONTAL UNITS
1. Position the unit to minimize long runs of duct or runs of
duct with many turns and elbows.
2. Unit can be mounted left or right side airflow configuration.
3. Position the unit on adequate supports or by using support
brackets (see Figure 8) and connect supply plenum.
4. If summer air conditioning is desired, position the indoor coil on
the supply air side of the unit. Insure that no air can bypass
this coil.
5. Secure the four angle brackets to the return air opening. See
Figure 9. Connect the return air ducting to the return air opening at the top of the unit. Make the connection air tight to prevent entraining combustion gases from an adjacent
fuel-burning appliance.
NOTE: Do not block furnace access with support rods. Maintain clearances recommended in Figure 8. Allow enough
space for proper service maintenance or replacement of the
heat exchanger and blower assembly.
DUCTING
FOUR ANGLE BRACKETS CAN BE INSTALLED HORIZONTALLY.
THESE BRACKETS MAY BE USED TO SECURE THE RETURN AIR
DUCT TO A HORIZONTAL UNIT.
RETURN
AIRFLOW
REAR VIEW
FIGURE 9
HORIZONTAL RETURN AIR DUCT
(LEFT-HAND AIRFLOW POSITION SHOWN)
FIGURE 8
HORIZONTAL FURNACE INSTALLED W/SUPPORT BRACKETS
ST-A1220-03
Ducting
NOTE:
HORIZONTAL LEFT ORIENTATION DEPICTED IN ILLUSTRATION.
HORIZONTAL RIGHT ORIENTATION IS SIMILAR IN INSTALLATION.
NOTE:
DO NOT BLOCK FURNACE ACCESS WITH
SUPPORT RODS, ALLOW SPACE FOR
PROPER SERVICE MAINTIENCE OR
REPLACEMENT OF THE HEAT EXCHANGER
AND BLOWER ASSEMBLY .
AIR FLOW
Page 14
14
Combustion Air
COMBUSTION AND VENTILATION AIR
1. IMPORTANT:
Air for combustion and ventilation must not
come from a corrosive atmosphere. Any failure due to corrosive elements in the atmosphere is excluded from warranty
coverage.
2. Combustion air must be free of acid forming chemicals; such
as sulphur, fluorine and chlorine. These elements are found in
aerosol sprays, detergents, bleaches, cleaning solvents, air
fresheners, paint and varnish removers, refrigerants and many
other commercial and household products. Vapors from these
products when burned in a gas flame form acid compounds.
The acid compounds increase the dew point temperature of
the flue products and are highly corrosive after they condense.
3. The following types of installation may require OUTDOOR AIR
for combustion, due to chemical exposures:
• Commercial buildings
• Buildings with indoor pools
• Furnaces installed in laundry rooms
• Furnaces in hobby or craft rooms
• Furnaces installed near chemical storage areas.
4. If combustion air is exposed to the following substances (but
not limited to the following), it should not be used and the furnace may require outdoor air for combustion.
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine-based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry curing and acid washing materials
Combustion air requirements are determined by whether the furnace is in an open (unconfined) area or in a confined space such
as a closet or small room.
When the furnace is installed in the same space with other gas appliances, such as a water heater, be sure there is an adequate
supply of combustion and ventilation air for the furnace and the
other appliances. Do not delete or reduce the combustion air supply required by the other gas appliances in this space. See Z223.1,
National Fuel Gas Code (NFPA 54). An unconfined space must
have at least 50 cubic feet (volume) for each 1,000 BTUH of the
total input of all appliances in the space. If the open space containing the appliances is in a building with tight construction (contemporary construction), outside air may still be required for the
appliances to burn and vent properly. Outside air openings should
be sized the same as for a confined space.
IMPORTANT: ONLY THE CURRENT VENT INSTRUCTIONS
APPLY. All gas furnaces cannot be common-vented.
OVERTEMPERATURE SAFETY
SWITCHES
Furnaces are equipped with safety switches in the burner compartment to protect against over-temperature conditions caused
by inadequate combustion air supply. If a switch is tripped it must
be manually reset after clearing the fault condition which caused
it to open.
IMPORTANT:
This is not a direct vent furnace. Review venting
instructions before installing.
!
WARNING
THIS FURNACE AND ANY OTHER FUEL-BURNING APPLIANCE MUST BE PROVIDED WITH ENOUGH FRESH AIR
FOR PROPER COMBUSTION AND VENTILATION OF THE
FLUE GASES. MOST HOMES WILL REQUIRE THAT OUTSIDE AIR BE SUPPLIED INTO THE FURNACE AREA. FAILURE TO DO SO CAN CAUSE DEATH FROM CARBON
MONOXIDE POISONING.
!
WARNING
ADEQUATE FACILITIES FOR PROVIDING AIR FOR COMBUSTION AND VENTILATION MUST BE PROVIDED IN ACCORDANCE WITH SECTION 5.3, AIR FOR COMBUSTION
AND VENTILATION, OF THE NATIONAL FUEL GAS CODE,
ANSI, Z223.1 LATEST EDITION OR APPLICABLE PROVISIONS FOR THE LOCAL BUILDING CODES, AND NOT
OBSTRUCTED SO AS TO PREVENT THE FLOW OF AIR TO
THE FURNACE.
COMBUSTION AIR REQUIREMENTS
!
WARNING
ALL FURNACE INSTALLATIONS MUST COMPLY WITH
THE NATIONAL FUEL GAS CODE AND LOCAL CODES TO
PROVIDE ADEQUATE COMBUSTION AND VENTILATION
AIR FOR THE FURNACE. FAILURE TO DO SO CAN CREATE HAZARDOUS CONDITIONS RESULTING IN PROPERTY DAMAGE, BODILY INJURY OR DEATH FROM
SMOKE, FIRE OR CARBON MONOXIDE.
!
WARNING
DO NOT BYPASS, JUMPER, OR REMOVE ANY SAFETY
SWITCH FROM THE FURNACE CONTROL CIRCUIT. IF A
SAFETY SWITCH CAUSES THE FURNACE TO SHUT
DOWN OR OPERATE INTERMITTENTLY, IT IS AN INDICATION OF A POTENTIAL SAFETY HAZARD THAT MUST BE
ADDRESSED BY A QUALIFIED TECHNICIAN, SERVICE
AGENCY OR THE GAS SUPPLIER. DO NOT RESET
SAFETY CONTROLS WITHOUT CORRECTIVE ACTION
AND/OR VERIFICATION OF PROPER SAFE OPERATION
BY A QUALIFIED INSTALLER, SERVICE AGENCY OR THE
GAS SUPPLIER.
REPLACE ANY SAFETY CONTROL COMPONENT ONLY
WITH IDENTICAL OEM REPLACEMENT PARTS
Page 15
15
COMBUSTION AND VENTILATION AIR (cont.)
For improved indoor air quality, added safety and product performance we recommend direct vent type installations. If non-direct type vent system is used, the requirements for combustion
air must be provided as identified in the National Fuel Gas Code.
Combustion air requirements are determined by whether the furnace is in an open (unconfined) area or in a confined space such
as a closet or small room.
FURNACE LOCATED IN AN UNCONFINED SPACE
USING INDOOR AIR FOR COMBUSTION:
An unconfined space must have at least 50 cubic feet for each
1,000 BTUH of total input for all appliances in the space. Table 1
below specifies minimum space requirements and a few examples of the room sizes required for different inputs. The sizes are
based on 8-foot ceilings.
If the open space containing the furnace is in a building with tight
construction, outside air may still be required for the furnace to
operate and vent properly. Outside air openings should be sized
the same as for a confined space.
FURNACE LOCATED IN A CONFINED
SPACE
A confined space is defined as any space for a given furnace input
rating which is smaller than that which is specified in Table 1 as
minimum for an “unconfined” space. If the space is less than that
specified in this table, the space is defined as
“confined”.
If the space is small enough to be designated as “confined”, it
must have openings into the space which are located in accordance with the requirements set forth in the following subsections
A and B. Size connected to the heated area or to the outside, and
by the input of ALL
appliances in the space.
If the confined space is within a building with tight construction,
combustion air must be taken from outdoors or from an area
freely communicating with the outdoors.
A. USING INDOOR AIR FOR COMBUSTION:
IMPORTANT: Air should not be taken from a heated space
with a fireplace, exhaust fan or other device that may produce negative pressure.
If combustion air is taken from the heated area, the openings
must each have at least 100 square inches of free area.
Each opening must have at least one square inch of free
area for each 1,000 BTUH of total input in the space. Table 2
shows some typical examples of openings required for combustion air openings required for a confined space.
B. USING OUTDOOR AIR FOR COMBUSTION:
IMPORTANT: Do not take air from an attic space that is
equipped with power ventilation.
The confined space must communicate with the outdoors in
accordance with Methods 1 or 2 below. The minimum dimension of air openings shall not be less than 3 inches. Where
ducts are used, they shall be of the same cross-sectional
area as the free area of the openings to which they connect.
METHOD 1:
Two permanent openings, one located within 12 inches of the
top and one located within 12 inches of the bottom of the enclosure, shall be provided. The openings shall communicate
directly, or by ducts, with the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
Combustion Air
COMBUSTION AIR REQUIREMENTS: CONFINED AND
UNCONFINED SPACES
!
WARNING
ALL FURNACE INSTALLATIONS MUST COMPLY WITH
THE NATIONAL FUEL GAS CODE, NFPA 54 AND LOCAL
CODES TO PROVIDE ADEQUATE COMBUSTION AND
VENTILATION AIR FOR THE FURNACE. FAILURE TO DO
SO CAN RESULT IN EXPLOSION, FIRE, PROPERTY DAMAGE, CARBON MONOXIDE POISONING, PERSONAL INJURY OR DEATH.
!
WARNING
READ AND FOLLOW THE GENERAL VENTING REQUIREMENTS AND GUIDELINES OF THIS MANUAL FOR ADDI-
TIONAL VENTING REQUIREMENTS PERTAINING TO ALL
FURNACE INSTALLATIONS (INCLUDING DIRECT AND
NON-DIRECT VENTING). FAILURE TO FOLLOW ALL INSTRUCTIONS IN THIS MANUAL CAN RESULT IN EQUIPMENT FAILURE, EQUIPMENT DAMAGE, PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
150,000 7,500 940 32 x 30
TABLE 1: MINIMUM SPACE REQUIREMENTS
FOR UNCONFINED SPACE, NON-DIRECT VENT
150,000 150
TABLE 2: MINIMUM FREE AREA
OPENING REQUIRED FOR A
FURNACE LOCATED IN A
CONFINED SPACE USING
INDOOR AIR FOR COMBUSTION.
TABLE 8: MINIMUM FREE AREA OPENING REQUIRED FOR A FURNACE LOCATED IN A CONFINED SPACE USING INDOOR AIR FOR COMBUSTION.
Free Area for Each
Input (BTUH)
50,000 100
75,000 100
100,000 100
125,000 130
Opening (sq inches)
TABLE 7: MINIMUM SPACE REQUIREMENTS FOR UNCONFINED SPACE, NON-DIRECT VENT*
Input
(BTUH)
50,000 2,500 313 16 x 20
75,000 3,750 470 24 x 20
100,000 5,000 625 32 x 20
125,000 6,300 790 36 x 30
Minimum
Space
(Cubic Ft)
Minimum Area
with 8
Ceilings (sq )
Typical Room
Size w/ 8'
Ceilings ( x )
Page 16
A. Where directly communicating with the outdoors through an
opening or where communicating to the outdoors through
vertical ducts as shown in Figure 11, each opening shall
have a minimum free area of 1 square inch for each 4,000
BTUH of total appliance input rating of all equipment in the
enclosure. Table 3 specifies the minimum area for
each of the 2 combustion air openings and minimum round
duct diameter for direct openings and vertical ducting only.
B. Where communicating with the outdoors through horizontal ducts, each opening shall have a minimum free area of 1
square inch for each 2,000 BTUH of total appliance input rating of all equipment in the enclosure (see Figure 12). Table 4
specifies the minimum area for each of the 2 combustion air
openings and minimum round duct diameter for horizontal
ducting only.
METHOD 2:
One permanent opening located within 12 inches of the top of
the enclosure, shall be permitted where the equipment has
clearances of at least 1 inch from the sides and back and 6
inches from the front of the appliance. The opening shall directly communicate with the outdoors or communicate
through a vertical or horizontal duct to the outdoors or spaces
(crawl or attic) that freely communicate with the outdoors,
and shall have a minimum of:
150,000 38 8
TABLE 3: MINIMUM FREE AREA REQUIRED
FOR EACH OPENING (WHEN TWO OPENINGS
ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE
3. OUTSIDE THROUGH AN OPENING OR
3. THROUGH A VERTICAL DUCT.
16
Combustion Air
COMBUSTION AND VENTILATION AIR (cont.)
150,000 75 10
TABLE 4: MINIMUM FREE AREA REQUIRED
FOR EACH OPENING (WHEN TWO OPENINGS
ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE
3. OUTSIDE THROUGH A HORIZONTAL DUCT.
150,000 75 10
TABLE 5: MINIMUM FREE AREA REQUIRED
FOR EACH OPENING (WHEN TWO OPENINGS
ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE
3. OUTSIDE THROUGH A HORIZONTAL DUCT.
COMBUSTION AIR REQUIREMENTS: CONFINED AND
UNCONFINED SPACES
GAS
WATER
HEATER
FURNACE
12”
MAX
12”
MAX
NOTE:
EACH OPENING SHALL
HAVE A FREE AREA OF
NOT LESS THAN ONE
SQUARE INCH PER
1,000 BTU PER HOUR OF
THE TOTAL INPUT
RATING OF ALL
EQUIPMENT IN THE
ENCLOSURE, BUT NOT
LESS THAN 100
SQUARE INCHES.
ST-A1227-01
FIGURE 10
NON-DIRECT VENT
AIR FROM
HEATED
SPACE
VENT PENETRATIONS
FORNONDIRECTVENTFURNACES
AIR FROM HEATED SPACE
TABLE 9: MINIMUM FREE AREA REQUIRED FOR EACH OPENING (WHEN TWO OPENINGS ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE OUTSIDE THROUGH AN OPENING OR THROUGH A VERTICAL VENT DUCT.*
Free Area for
Total Input for
ALL Gas
Appliances
(BTUH)
50,000 13 5
75,000 19 5
100,000 25 6
125,000 32 8
TABLE 10: MINIMUM FREE AREA REQUIRED FOR EACH OPENING (WHEN TWO OPENINGS ARE USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE OUTSIDE THROUGH A HORIZONTAL DUCT.
Total Input for
ALL Gas
Appliances
(BTUH)
50,000 25 6
75,000 38 8
100,000 50 8
125,000 63 10
Each Opening
w h e n 2 S e p a r a t e
Openings are
used (sq inches)
Free Area for
Each Opening
when 2 Separate
Openings are
used (sq inches)
R o u n d P i p e D u c t
Diameter ( Vercal
Duct Only) (inches)
Round Pipe Duct
Diameter
(Horizontal Duct
Only) (inches)
TABLE 11: MINIMUM FREE AREA REQUIRED FOR AN OPENING (WHEN ON E OPENING IS USED) WITH A FURNACE:
1. LOCATED IN A CONFINED SPACE
2. USING OUTDOOR AIR FOR COMBUSTION
3. COMMUNICATING DIRECTLY TO THE OUTSIDE.
Total Input for
ALL Gas
Appliances
(BTUH)
50,000 25 6
75,000 38 8
100,000 50 8
125,000 63 10
*
Free Area for an
Opening when 1
Opening is used
(sq inches)
Round Pipe Duct
Diameter (inches)
Page 17
17
COMBUSTION AND VENTILATION AIR (cont.)
A. 1 Square inch for each 3,000 BTUH of the total input rat-
ing of all equipment located in the enclosure
and
B. Not less than the sum of the areas of all vent connectors
in the confined space.
If the unit is installed where there is an exhaust fan, sufficient
ventilation must be provided to prevent the exhaust fan from creating negative pressure.
AIR INTAKE PIPE CONNECTION
A double-elbow may be installed to top inlet air opening,
BUT IS NOT REQUIRED. This will help to prevent accidental
blockage of the intake opening. Reference Figure 13 for
proper elbow diameter.
NOTE: Inlet is specifically designed to prevent material from
being pulled into furnace. If elbows are not used, the intake opening must be kept clean and free of debris.
ATTACH OPTIONAL DOUBLE ELBOW TO TOP INLET AIR
OPENING TO PREVENT ACCIDENTAL BLOCKAGE OF
INTAKE OPENING. THIS IS NOT A REQUIREMENT. (SEE
PREVIOUS PAGE.) SINGLE ELBOW IS ALLOWED BUT
MAY NOT PREVENT DEBRIS FROM BEING DROPPED
INTO THE FURNACE.
GROUND OR
SHELF SURFACE
6" MIN.
6" MININUM
CLEARANCE
PVC
DOUBLE
ELBOW
#8 SCREWS
METAL FLUE
PIPE ONLY
EXHAUST
#8 SCREWS
FIGURE 13
COMBUSTION AIR FITTING – NON-ATTIC COMBUSTION AIR PULL
Combustion Air
COMBUSTION AIR REQUIREMENTS: CONFINED AND
UNCONFINED SPACES
GAS
WATER
HEATER
FURNACE
OPTIONAL 1 SQ. INCH PER 4000 BTUH INLET AIR
GABLE
VENT
VENTILATED
ATTIC GABLE OR
SOFFIT VENTS
OUTLET AIR
IN ATTIC
MUST BE
ABOVE
INSULATION
1 SQ. INCH PER
4000 BTUH INLET AIR
12” MAX
1 SQ. INCH PER
4000 BTUH
OUTLET AIR
GAS
WATER
HEATER
FURNACE
12”
MAX
INLET AIR 1 SQ. INCH
PER 2000 BTUH
OUTLET AIR 1 SQ. INCH
PER 2000 BTUH
OUTLET AIR
1 SQ. INCH PER
4000 BTUH
INLET AIR
1 SQ. INCH PER
4000 BTUH
ST-A1227-03
ST-A1227-02
FIGURE 11
NON-DIRECT VENT
AIR FROM ATTIC
OR CRAWL
SPACE
FIGURE 12
NON-DIRECT VENT
OUTSIDE AIR
USING A
HORIZONTAL
DUCT
VENT PENETRATIONS
FORNONDIRECTVENTFURNACES
AIR FROM ATTIC/CRAWL SPACE
VENT PENETRATIONS
FORNONDIRECTVENTFURNACES
AIR FROM ATTIC/CRAWL SPACE
Page 18
Combustion Air
18
COMBUSTION AND VENTILATION AIR (cont.)
It is also acceptable to run the condensate drain (or refrigerant) line access over the air intake hole as long as a 1" minimum clearance is maintained.
Combustion air openings must not be restricted in any manner.
IMPORTANT: When indoor combustion air is used, the inlet air
opening at the furnace must be protected from accidental blockage.
IMPORTANT:
If the furnace is in a location with an exhaust fan,
there must be sufficient ventilation to prevent the exhaust fan
from creating a negative pressure in the room.
Combustion air openings must NOT BE RESTRICTED in any
manner.
CONSULT LOCAL CODES FOR SPECIAL REQUIREMENTS.
B: Method 3
For the optimum in quiet operation, attic air may be brought directly to the furnace.
IMPORTANT: In applications using Method 3 for combustion air,
the attic must be ventilated by gable or soffit vents.
COMBUSTION AIR FROM ATTIC
If attic combustion air is used, the inlet air opening at the furnace
must be protected from accidental blockage. Install a 90° elbow
pointing horizontally at the top of inlet air pipe. See Figure 14
(maximum of 2, 45° or 90° elbows, allowed).
NOTE: Maximum length of pipe that may be used for combustion
air is 10 feet with two elbows. Lengths of more than 10 feet can
result in nuisance pressure switch trips.
!
CAUTION
COMBUSTION AIR INTAKES CANNOT BE TERMINATED
OUTSIDE. DOING SO CAN CAUSE IMPROPER OPERATION OF THE FURNACE.
INCLUDING
HORIZONTAL DIRECTION
ATTACH A 90° ELBOW TO TOP INLET AIR
OPENING TO PREVENT ACCIDENTAL BLOCKAGE
OF INTAKE OPENING.
CAUTION
!
PVC
ELBOW
#8 SCREWS
#8 SCREW
METAL FLUE PIPE ONLY
10 FT. MAX.
12" MIN. FROM
TOP OF INSULATION
6" MINIMUM
CLEARANCE
PVC
COUPLER
EXHAUST
ATTIC SPACE
INDOOR SPACE
INSULATION
USE OF SHEET METAL
AIR INTAKE PIPE INSTEAD
OF PVC MAY RESULT IN
NOISE ISSUES.
FIGURE 14
COMBUSTION AIR FITTING – OPTIONAL ATTIC COMBUSTION AIR PULL
Page 19
19
COMBUSTION AND VENTILATION AIR (cont.)
GENERAL INFORMATION
The furnace must be vented in accordance with these instructions,
National Fuel Gas Code, ANSI Z223.1 and requirements or codes
of the local utility or other authority having jurisdiction.
DRAFT INDUCER
FURNACE CATEGORY INFORMATION
This furnace is shipped as a Category I type induced draft furnace. A Category I furnace operates with a nonpositive vent pressure and has a vent gas temperature at least 140°F above the
dew point of the vent gases. A Category I type may be a draft
hood equipped furnace or have a fan assisted combustion system (induced draft). The inducer is used to pull flue products
through the combustion chamber and as they leave the furnace,
most of the energy has been dissipated. The buoyant effect of the
flue gases provides venting to the outdoors.
During the off cycle, the inducer is off and there is very little flow
through the vent, cooling the vent. During the on cycle there is no
dilution airflow, as with a draft hood type furnace. Although the
vent heats up rapidly without dilution air, the flue products contain
more water vapor, which results in a higher dew point temperature. It is most important that you follow the guidelines in these
instructions to prevent the possible formation of condensation in
the venting system.
As a Category I furnace it may be vented vertically with type B-1
vent pipe and also may be common vented, as described in
these instructions.
IMPORTANT APPLICATION NOTES
When the furnace is used as a replacement, the existing vent
system should be inspected to assure that there are no obstructions, blockage, or any signs of corrosion and is properly sized for
use with this furnace.
NOTE: When the vent table permits more than one diameter of
pipe for a connector or vent, the smallest permitted diameter
must be used.
Vent pipe may be type “B-1,” either rigid or suitable flexible construction that carries a U.L. listing.
Common venting is allowed with vertical B-1 vent systems, and
lined masonry chimneys. Follow the National Fuel Gas Code,
ANSI Z223.1.
NOTE: Follow combustion air instructions as outlined in this manual.
Single wall vent connectors to “B-1 vent or masonry chimneys”
may be used under the guidelines of the National Fuel Gas Code,
ANSI Z223.1.
The entire length of the vent connector shall be readily accessible for inspection, cleaning and replacement.
“B-1” VERTICAL VENTING
NOTE: Refer to the National Fuel Gas Code, ANSI Z223.1.
Type “B-1” vents must be installed in accordance with the terms
of their listings and the vent manufacturer’s instructions.
“B-1” vents must be supported and spaced in accordance with
their listings and the manufacturer’s instructions. All vents must
be supported to maintain their minimum clearances from combustible material.
*NOTE: All furnaces have a 3” vent connection as shipped from the factory. A 3” to 4”, 3” to 5”, or 4” to 5” vent transition may be required when
vertically vented or common vented with metal vent pipes. THE VENT
TRANSITION CONNECTION MUST BE MADE AT THE FURNACE
VENT EXIT. It must originate with an adapter if required, at the furnace
flue collar and terminate either in a listed cap or roof assembly. When
common venting, the vent connector size may differ from the above diameters depending on application. See National Fuel Gas Code ANSI
Z223.1 or latest edition tables.
!
WARNING
DEVICES ATTACHED TO THE FLUE OR VENT FOR THE
PURPOSE OF REDUCING HEAT LOSS UP THE CHIMNEY
HAVE NOT BEEN TESTED AND HAVE NOT BEEN INCLUDED IN THE DESIGN CERTIFICATION OF THIS FURNACE. WE, THE MANUFACTURER, CANNOT AND WILL
NOT BE RESPONSIBLE FOR INJURY OR DAMAGE
CAUSED BY THE USE OF SUCH UNTESTED AND/OR UNCERTIFIED DEVICES, ACCESSORIES OR COMPONENTS.
!
WARNING
VENT PIPE ATTACHING HOLES MUST BE PREDRILLED
IN THE DRAFT INDUCER COLLAR TO PREVENT DAMAGING THE INDUCER. DRILL 1/8” DIAMETER HOLES
THROUGH THE VENT PIPE AND COLLAR AND USE #8
SCREWS TO ATTACH. SEE FIGURE 16. FAILURE TO FOLLOW THIS WARNING CAN CAUSE RECIRCULATION OF
FLUE PRODUCTS CAUSING CARBON MONOXIDE POISONING RESULTING IN PERSONAL INJURY OR DEATH.
VENTING
VERTICAL VENTING
Categorized
Furnace Vent
Input Size Recommended
(See NFGC)
50K 3”
75K *4”
100K *4”
125K *5”
150K *5”
Combustion Air
Page 20
20
Combustion Air
COMBUSTION AND VENTILATION AIR (cont.)
VERTICAL VENT SYSTEMS:
1. A gas vent shall terminate above the roof surface with a listed
cap or listed roof assembly. Gas vents 12 inches in size or
smaller with listed caps shall be permitted to be terminated in
accordance with Figure 15, provided they are at least 8 feet
from a vertical wall or similar obstruction. All other gas vents
shall terminate not less than 2 feet above the highest point
where they pass through the roof and at least 2 feet higher
than any portion of a building within 10 feet.
2. A type B-1 gas vent shall terminate at least 5 feet in vertical
height above the highest connected equipment draft hood or
flue collar.
3. Must rise
1
/4” per foot away from the furnace on horizontal runs
and be supported with straps or hangers so it has no sags or
dips. Supports at 4 foot intervals and at all elbows are recommended.
4. The vent connector must be mechanically fastened to the outlet collar of the furnace with at least (2) sheet metal screws except vent connectors that are B-1 material. These shall be
assembled in accordance with the manufacturer’s instructions.
See Figures 16 and 17.
5. Any angle greater than 45 degrees from the vertical is considered horizontal. The total horizontal distance of a vent plus the
horizontal vent connector serving draft-hood equipped appliances shall not be greater than 75 percent of the vertical
height of the vent.
Single appliance venting of a fan assisted furnace into a tile-lined
masonry chimney is prohibited. The chimney must be lined with
either Type B vent or with a listed, single wall, metal lining system. Reference National Fuel Gas Code, ANSI Z223.1. See Figure 18 for typical B-1 vent chase.
NOTE: A chimney adapter is available as an accessory (see accessory section of this manual). Follow manufacturer’s instructions.
SPECIAL VENT SYSTEMS (SVS)
IMPORTANT:
It is THE FURNACE MANUFACTURER’s position
now that new
installations of any HTPV pipe used in a category
III
vent application, including Selkirk’s Selvent™ IIHTPV prod-
uct, should cease immediately.
!
WARNING
DO NOT CONNECT THIS FURNACE TO A CHIMNEY USED
TO VENT A SOLID FUEL APPLIANCE (WOOD OR COAL).
VENTING WITH A SOLID FUEL APPLIANCE CAN LEAD TO
IMPROPER FUNCTIONING OF THE UNIT, AND DUE TO
SOOTING, THE POSSIBILITY OF FIRE RESULTING IN
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
OVER 7/12 TO 8/12 1.5
OVER 8/12 TO 9/12 2.0
OVER 9/12 TO 10/12 2.5
OVER 10/12 TO 11/12 3.25
OVER 11/12 TO 12/12 4.0
OVER 12/12 TO 14/12 5.0
OVER 14/12 TO 16/12 6.0
OVER 16/12 TO 18/12 7.0
ST-A1220-24
OVER 18/12 TO 20/12 7.5
OVER 20/12 TO 21/12 8.0
ROOFPITCH = X/12
Page 21
21
COMBUSTION AND VENTILATION AIR (cont.)
FIGURE 18
DEDICATED VENTING THROUGH
CHIMNEY WITH “B-1” VENT
Combustion Air
FIGURE 17
ST-A1220-09
FRESH AIR INLET
1. STANDARD 3” FLUE CONNECTION.
2. 4” ADAPTER - OPTIONAL
SEENATI ONAL FUEL GAS CODE FOR SIZING OPTIONS
1.
2.
ST-A1220-09-01
Page 22
22
COMBUSTION AND VENTILATION AIR (cont.)
POWER VENT SYSTEMS
When vertical venting is not possible, the only acceptable method
for horizontal venting is with the use of Tjernlund model GPAK1TR or Field Controls models SWG-4R power venter. Type B
vent pipe and fittings must be used. Common venting is not permitted
All application and installation instructions supplied with the
power venter must be followed.
Please address all questions regarding power venter installation,
agency listings and furnace model compatibility to:
Tjernlund Products, Inc.
(800) 255-4208 or (612) 426-2993
Field Controls L.L.C.
(800) 742-8368 or (919) 522-0214
EXISTING VENT SYSTEMS
IMPORTANT RETROFIT
VENTING INSTRUCTIONS
If this furnace is a replacement installation, ALWAYS INSPECT
the existing vent system to be sure there are no obstructions,
blockages, or signs of corrosion.
When the existing furnace is removed from a venting system
serving other appliances, the venting is likely to be too large to
properly vent the remaining attached appliances.
The following steps shall be followed with each appliance that remains connected to the common venting system, while the other
appliances that remain connected to the common venting systems are not in operation.
NOTE: When the vent table permits more than one diameter
of pipe for a connector or vent, the smallest permitted diameter must be used.1. Seal any unused openings in the common venting system.
NOTE: Ensure existing venting system complies with latest addi-
tion of National Fuel Gas Code ANSI Z223.1 and all local
codes/regulations.
1. Visually inspect the venting system for proper size and horizontal pitch and determine that there is no blockage, restriction, leakage, corrosion or other deficiencies which could
cause an unsafe condition.
2. Insofar as is practical, close all building doors, windows and all
doors between the space where the appliances remaining connected to the common venting system are located. Turn on
clothes dryers and any appliance not connected to the common venting system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan. Close fireplace dampers.
3. Follow the lighting instructions. Place the appliance being inspected into operation. Adjust the thermostat so the appliance
will operate continuously.
4. Test for spillage at the draft hood relief opening after 5 minutes
of main burner operation. Use the flame of a match or candle,
or smoke from a cigarette, cigar, or pipe.
5. After it has been determined that each appliance that remains
connected to the common venting system properly vents
(when tested as outlined above) return doors, windows, exhaust fans, fireplace dampers and any other gas-burning appliance to their previous conditions of use.
6. If improper venting is observed during any of the above tests,
the common venting system must be resized. Refer to National
Fuel Gas Code, ANSI Z223.1.
Combustion Air
Page 23
23
Gas Supply
IMPORTANT SAFETY INFORMATION
NATURAL GAS AND PROPANE
(LIQUEFIED PETROLEUM GAS / LPG)
SAFETY
GAS SUPPLY
GAS SUPPLY
GAS SUPPLY AND PIPING
!
WARNING
• FURNACES USING PROPANE GAS ARE DIFFERENT FROM NATURAL GAS MODELS. A NATURAL
GAS HEATER WILL NOT FUNCTION SAFELY ON
PROPANE AND VICE VERSA. CONVERSIONS OF
HEATER GAS TYPE SHOULD ONLY BE MADE BY
QUALIFIED INSTALLERS USING FACTORY SUPPLIED COMPONENTS. THE FURNACE SHOULD
ONLY USE THE FUEL TYPE IN ACCORDANCE
WITH LISTING ON RATING PLATE. ANY OTHER
FUEL USAGE WILL RESULT IN DEATH OR SERIOUS PERSONAL INJURY FROM FIRE AND/OR EXPLOSION.
• BOTH NATURAL GAS AND PROPANE HAVE AN
ODORANT ADDED TO AID IN DETECTING A GAS
LEAK. SOME PEOPLE MAY NOT PHYSICALLY BE
ABLE TO SMELL OR RECOGNIZE THIS ODORANT.
IF YOU ARE UNSURE OR UNFAMILIAR WITH THE
SMELL OF NATURAL GAS OR PROPANE, ASK
YOUR LOCAL GAS SUPPLIER. OTHER CONDITIONS, SUCH AS “ODORANT FADE,” WHICH
CAUSES THE ODORANT TO DIMINISH IN INTENSITY, CAN ALSO HIDE, CAMOUFLAGE, OR OTHERWISE MAKE DETECTING A GAS LEAK BY
SMELL MORE DIFFICULT.
• UL OR CSA RECOGNIZED FUEL GAS DETECTORS
ARE RECOMMENDED IN ALL ENCLOSED
PROPANE AND NATURAL GAS APPLICATIONS
WHEREIN THERE IS A POTENTIAL FOR AN EXPLOSIVE MIXTURE OF FUEL GAS TO ACCUMULATE.
FUEL DETECTOR INSTALLATION SHOULD BE IN
ACCORDANCE WITH THE DETECTOR MANUFACTURER’S RECOMMENDATIONS AND/OR LOCAL
LAWS, RULES, REGULATIONS, OR CUSTOMS.
• BEFORE ATTEMPTING TO LIGHT THE FURNACE,
MAKE SURE TO LOOK AND SMELL FOR GAS
LEAKS. USE A SOAPY SOLUTION TO CHECK ALL
GAS FITTINGS AND CONNECTIONS.
BUBBLING AT A CONNECTION INDICATES A LEAK
THAT MUST BE CORRECTED. WHEN SMELLING TO
DETECT A GAS LEAK, BE SURE TO ALSO SNIFF
NEAR THE FLOOR. PROPANE GAS IS HEAVIER
THAN AIR AND TENDS TO COLLECT AT LOWER
LEVELS MAKING IT MORE DIFFICULT TO SMELL AT
NOSE LEVEL. NATURAL GAS IS LIGHTER THAN AIR
AND WILL RISE, POSSIBLY ACCUMULATING IN
HIGHER PORTIONS OF THE STRUCTURE.
• IF A GAS LEAK IS PRESENT OR SUSPECTED:
- DO NOT ATTEMPT TO FIND THE CAUSE YOURSELF.
- NEVER
USE AN OPEN FLAME TO TEST FOR GAS
LEAKS. THE GAS CAN IGNITE RESULTING IN
DEATH, PERSONAL INJURY, OR PROPERTY
DAMAGE.
-DO NOTTRY TO LIGHT ANY APPLIANCE.
-DO NOT
TOUCH AND ELECTRICAL SWITCH.
-DO NOT
USE ANY PHONE IN YOUR BUILDING.
- LEAVE THE BUILDING IMMEDIATELY AND CALL
THE GAS SUPPLIER FROM A NEIGHBOR’S
PHONE. FOLLOW THE GAS SUPPLIER’S INTRUCTIONS.
- IF YOU CANNOT REACH YOUR GAS SUPPLIER,
CALL THE FIRE DEPARTMENT.
- DO NOT RETURN TO THE BUILDING UNTIL AUTHORIZED BY THE GAS SUPPLIER OR FIRE DEPARTMENT.
• SHOULD OVERHEATING OCCUR OR THE GAS
SUPPLY FAIL TO SHUT OFF, TURN OFF THE MANUAL GAS CONTROL VALVE TO THE FURNACE.
• CONSULT WITH THE LOCAL BUILDING DEPART
MENT AND FUEL GAS SUPPLIER BEFORE INSTALLING THE HEATER:
- THE INSTALLATION AND PURGING OF GAS PIPING MUST CONFORM TO LOCAL CODES, UTILITY COMPANY REQUIREMENTS, AND THE
LATEST EDITION OF NATIONAL FUEL GAS
CODE (NFGC) - ANSI Z223.1/NFPA 54.
- LP FURNACES SHOULD NOT BE INSTALLED
BELOW GRADE (IN A BASEMENT FOR EXAMPLE) IF SUCH INSTALLATION IS PROHIBITED BY
FEDERAL, STATE, PROVINCIAL, AND/OR LOCAL
LAWS, RULES, REGULATIONS, OR CUSTOMS.
- INSTALLATION OF A GAS PRESSURE REGULATOR MAY BE REQUIRED IN THE GAS SUPPLY
LINE. THE REGULATOR SHOULD NOT EXCEED
THE MAXIMUM SUPPLY PRESSURE LISTED ON
THE FURNACE RATING PLATE. DO NOT USE AN
INDUSTRIAL-TYPE GAS REGULATOR.
- FOLLOW ALL LOCAL CODES AND SECTION 8.3
OF NFGC WITH REGARD TO PURGING OF GAS
PIPING TO ENSURE THAT THE AIR AND/OR FUEL
GAS IN THE GAS PIPING IS PROPERLY VENTED
TO A LOCATION WHERE AN EXPLOSIVE MIXTURE CANNOT ACCUMULATE.
(Continued on next column)
Page 24
24
Gas Supply
GAS SUPPLY
IMPORTANT:
Any additions, changes or conversions required for
the furnace to satisfactorily meet the application should be made
by a qualified installer, service agency or the gas supplier, using
factory-specified or approved parts.
IMPORTANT:
Connect this furnace only to gas supplied by a
commercial utility or commercial fuel provider.
IMPORTANT:
A U.L. or CSA recognized fuel gas and CO detector(s) are recommended in all applications, and their installation
should be in accordance with the detector manufacturer’s recommendations and/or local laws, rules, regulations or customs.
Install the gas piping according to all local codes, state codes and
regulations of the utility company, whichever holds jurisdiction.
If possible, run a separate gas supply line directly from the meter
to the furnace. Consult the local gas company for the location of
the manual main shut-off valve. The gas line and manual gas
valve must be adequate in size to prevent undue pressure
drop and never smaller than the pipe size to the combination
gas valve on the furnace. Refer to Table 6 for the recom mended
pipe size for natural gas and Table 7 for LP gas pipe sizes.
IMPORTANT:
It is permissible to run flexible gas connector inside
the unit to a piece of black pipe. If local codes allow the use of a
flexible gas appliance connector, always use a new listed connector. Do not use a connector which has previously serviced another
gas appliance. Massachusetts law limits flexible gas connectors to
a maximum of 36”.
Install a ground joint union outside the cabinet and within 3
feet to easily remove the control valve assembly. Install a
manual shut-off valve in the gas line outside the furnace casing. The valve should be readily accessible to turn the gas supply
on or off. Install a drip leg in the gas supply line as close to the furnace as possible. Always use a pipe compound resistant to the
action of liquefied petroleum gases on all threaded connections.
IMPORTANT:
When making gas pipe connections, use a back-up
wrench to prevent any twisting of the control assembly and gas
valve. Do not overtighten the connection.
Any strains on the gas valve can change the position of the gas
orifices in the burners. This can cause erratic furnace operation.
IMPORTANT:
ENSURE that the furnace gas control valve not be
subjected to high gas line supply pressures.
DISCONNECT the furnace and its individual shut-off valve from
the gas supply piping during any pressure testing that exceeds
1/2 PSIG (3.48 kPa).
GAS PIPE INSTALLATION
GAS VALVE
MANIFOLD
MANIFOLD
FLAME SENSOR
FLAME SENSOR
BURNERS
BURNERS
DIRECT SPARK
IGNITOR
DIRECT
SPARK
IGNITOR
MANUAL GAS VALVE
(IN CLOSED POSITION)
UNION
DUCT
UNION
DRIP LEG
DRIP LEG
4 TO 5 FEET
ABOVE FLOOR
REQ'D BY SOME
UTILITIES
4 TO 5 FEET
ABOVE FLOOR
REQ'D BY SOME
UTILITIES
UPFLOW
HORIZONTAL
GAS VALVE
FIGURE 19
GAS PIPING INSTALLATION
MANUAL GAS VALVE
(IN CLOSED
POSITION)
GAS PIPING
!
WARNING
THIS FURNACE IS EQUIPPED AT THE FACTORY
FOR USE ON NATURAL GAS ONLY. CONVERSION
TO LP GAS REQUIRES A SPECIAL KIT IS AVAILABLE AT THE DISTRIBUTOR. FAILURE TO USE THE
PROPER CONVERSION KIT CAN CAUSE FIRE,
CARBON MONOXIDE POISONING, EXPLOSION,
PROPERTY DAMAGE, PERSONAL INJURY OR
DEATH. SEE THE CONVERSION KIT INDEX SUPPLIED WITH THE FURNACE. THIS INDEX IDENTIFIES THE PROPER LP GAS CONVERSION KIT
REQUIRED FOR EACH PARTICULAR FURNACE.
Page 25
25
GAS SUPPLY (cont.)
IMPORTANT: ENSURE that the furnace gas valve is not to be
subjected to high gas line supply pressures.
DISCONNECT the furnace and its individual manual gas stop
from the gas supply piping during any pressure testing that ex-
ceeds 1/2 PSIG. (3.48 kPa).
Natural gas supply pressure must be 5" to 10.5" w.c. LP gas
supply pressure must be 11" to 13" w.c.
This pressure must
be maintained with all other gas-fired appliances in operation.
The minimum gas supply pressure to the gas valve for proper furnace input adjustments is 5" w.c. for natural gas, however 6" to 7"
is recommended. The minimum gas supply pressure is 11" w.c.
for LP gas.
GAS VALVE
This furnace has a 24-volt gas valve. It has ports for measuring
supply and manifold gas pressure. The valve body contains a
pressure regulator to maintain proper manifold gas pressure.
A control switch is on the valve body. It can be set to only the
“ON” or “OFF” positions. The gas valve is a slow-opening valve.
See Figure 20.
When energized, it takes 2 to 3 seconds to fully open.
GAS PRESSURE
!
CAUTION
ELEVATIONS ABOVE 2000 FT. REQUIRE THAT THE
FURNACE INPUT RATING BE ADJUSTED AND THAT
THE SIZE OF THE BURNER ORIFICES BE RECALCULATED BASED ON ELEVATION AND GAS HEATING VALUE. THE BURNER ORIFICES MAY (OR MAY
NOT) NEED TO BE CHANGED. SEE THE SECTION
TITLED “HIGH ALTITUDE INSTALLATIONS” OF THIS
BOOK FOR INSTRUCTIONS.
!
WARNING
NEVER PURGE A GAS LINE INTO THE COMBUSTION CHAMBER. NEVER USE MATCHES, FLAME
OR ANY IGNITION SOURCE FOR CHECKING LEAKAGE. FAILURE TO ADHERE TO THIS WARNING CAN
CAUSE A FIRE OR EXPLOSION RESULTING IN
PROPERTY DAMAGE, PERSONAL INJURY OR
DEATH.
TO CHECK FOR GAS LEAKAGE, USE AN APPROVED CHLORIDE-FREE SOAP AND WATER SOLUTION, OR OTHER APPROVED METHOD.
TABLE 6
NATURAL GAS PIPE CAPACITY TABLE (CU. FT./HR.)
Capacity of gas pipe of different diameters and lengths in cu. ft. per hr. with pressure drop of 0.3 in. and specific
gravity of 0.60 (natural gas).
Nominal Length of Pipe, Feet
Iron Pipe
Size, Inches 10 20 30 40 50 60 70 80
1-1/2 1,600 1,100 890 760 670 610 560 530
After the length of pipe has been determined, select the pipe size which will provide the minimum cubic feet per hour
required for the gas input rating of the furnace. By formula:
Gas Input of Furnace (BTU/HR)
Cu. Ft. Per Hr. Required=
Heating Value of Gas (BTU/FT
3
)
The gas input of the furnace is marked on the furnace rating plate. The heating value of the gas (BTU/FT
3
) may be de-
termined by consulting the local natural gas utility or the LP gas supplier.
Gas Supply
FIGURE 20
TYPICAL GAS VALVE (WHITE RODGERS)
INLET
PRESSURE TAP
LOW-FIRE
MANIFOLD
PRESSURE
ADJUSTMENT
OUTLET PRESSURE TAP
HIGH-FIRE
MANIFOLD
PRESSURE
ADJUSTMENT
REGULATOR
CAPS
Page 26
26
GAS SUPPLY (cont.)
GAS PRESSURE
SETTING GAS PRESSURE
The maximum gas supply pressure to the furnace
must not exceed 10.5" w.c. natural gas, or 13" w.c. LP
gas.
The minimum supply gas pressure to the gas valve
should be 5⬙ w.c. natural gas or 11⬙ w.c. LP gas. A properly
calibrated manometer is required for accurate gas pressure measurements.
SUPPLY GAS PRESSURE
MEASUREMENT
An inlet pressure tap is on the input side of the gas valve.
1. With gas shut off to the furnace at the manual gas
valve outside the unit.
2. Loosen (do NOT remove) the inlet pressure tap using
a 3/32⬙ allen-head wrench (see Figure 20).
3. Connect a manometer to the pressure tap. The pressure tap requires a 5/16⬙ I.D. hose.
A kit is available from Prostock Replacement Parts
which includes the following:
A. 3/32⬙ allen-head wrench
B. 5/16⬙ to 1/4⬙ hose reducer fitting
C. Short piece of 5/16⬙ I.D. hose
Kit part number is: F0092-100300S1
4. Turn on the gas supply and operate the furnace and all
other gas-fired units on the same gas line as the furnace.
5. Note or adjust the line gas pressure to give:
A. 5⬙ - 10.5⬙ w.c. for natural gas.
B. 11⬙ - 13⬙ w.c. for LP gas.
6. Shut off the gas at the manual gas valve and remove
the manometer and hose.
7. Tighten the allen-head screw in the inlet pressure tap
using a 3/32⬙ allen-head wrench (see Figure 20).
8. Turn on the gas supply and check for gas leaks using
an approved leak detector. Do NOT
use a flame of any
kind to check for leaks. Repair any leaks and repeat.
If the supply gas line pressure is above these ranges, install an in-line gas regulator to the furnace for natural gas
units. With LP gas, have the LP supplier reduce the line
pressure at the regulator.
If supply gas line pressure is below these ranges, either remove any restrictions in the gas supply piping or enlarge
the gas pipe. See Tables 6 and 7. With LP gas, have the
LP supplier adjust the line pressure at the regulator.
MANIFOLD GAS PRESSURE
MEASUREMENT
Natural gas manifold pressure should be 3.5" (± .3)
w.c. for high fire and 1.8" (± .1) w.c. for low fire. LP gas
manifold pressure should be 10.0" (± .5) w.c. for high
fire and 4.9" (± .2) w.c. for low fire. Only small variations
in gas pressure should be made by adjusting the pressure
regulator.
1. With the gas to the unit shut off at the manual gas
valve outside the unit.
2. Loosen (do NOT
remove) the outlet pressure tap plug
using a 3/32⬙ allen-head wrench (see Figure 20).
3. Connect a manometer to this pressure tap. The pressure tap requires a 5/16⬙ I.D. hose.
A kit is available from Prostock Replacement Parts
which includes the following:
A. 3/32⬙ allen-head wrench
B. 5/16⬙ to 1/4⬙ hose reducer fitting
C. Short piece of 5/16⬙ I.D. hose
Kit part number is: F0092-100300S1
4. Turn on the gas supply and operate the furnace (apply
a heat call).
5. Note or adjust the manifold gas pressure to give:
A. 3.5⬙ (± .3) w.c. high fire/1.8⬙ (± .1) w.c. low fire
natural gas.
B. 10.0⬙ (± .5) w.c. high fire/4.9⬙ (± .2) w.c. low fire
L.P.G.
6. To adjust the pressure regulators, remove the regulator
caps. (See Figure 20.)
7. Turn the adjustment screw clockwise to increase pressure, or counterclockwise to decrease pressure.
8. Securely replace the regulator caps.
9. Shut off gas at the manual gas valve and remove the
manometer and hose.
10. Tighten the allen-head screw in the outlet pressure tap
using a 3/32⬙ allen-head wrench (see Figure 20).
11. Turn on the gas supply and apply a heat call to the furnace then check for gas leaks using an approved leak
detector. Do NOT
use a flame of any kind to check for
leaks. Repair any leaks and repeat.
Gas Supply
!
CAUTION
ELEVATIONS ABOVE 2000 FT. REQUIRE THAT THE
FURNACE INPUT RATING BE ADJUSTED AND THAT
THE SIZE OF THE BURNER ORIFICES BE RECALCULATED BASED ON ELEVATION AND GAS HEATING VALUE. THE BURNER ORIFICES MAY (OR MAY
NOT) NEED TO BE CHANGED. SEE THE SECTION
TITLED “HIGH ALTITUDE INSTALLATIONS” OF THIS
BOOK FOR INSTRUCTIONS.
Page 27
27
TABLE 7
LP GAS PIPE CAPACITY TABLE (CU. FT./HR.)
Maximum capacity of pipe in thousands of BTU per hour of undiluted liquefied petroleum gases (at 11 inches water
column inlet pressure).
(Based on a Pressure Drop of 0.5 Inch Water Column)
Example (LP): Input BTU requirement of unit, 120,000
Equivalent length of pipe, 60 ft. = 3/4" IPS required.
LP CONVERSION
LP Conversion
NOTE: The valve can be converted to use liquified petroleum
(LP) gas by replacing the pressure regulator spring with the
conversion kit spring. This LP kit spring allows the regulator
to maintain the proper manifold pressure for LP gas. See
Figure 21.
NOTE: Order the correct LP conversion kit from the furnace
manufacturer. Furnace conversion to LP gas must be performed by a qualified installer, service agency or the gas
supplier.
NOx MODELS
When converting furnaces equipped with NOx inserts to LP gas,
remove the NOx insert assemblies. Steps for removal are listed
below:
1. Turn off all electrical power and the gas supply to the furnace.
2. Remove the burner door from the furnace.
3. Remove the burner assembly – handle with care.
4. Remove the two screws attaching the NOx insert retainer
bracket to the center panel and remove NOx inserts.
5. Put the two screws back into the holes in the center panel.
6. Re-install the burner assembly.
7. Replace burner door.
8. Turn on electrical power and gas supply to the unit.
NOTE: Some NOx models may have one less NOx insert.
ORIFICE INSTALLATION
LP Gas is a manufactured gas that has consistent heating
value across most regions.
The Sea Level input should still be reduced by 4% per
thousand ft. and the orifice size must be selected based on
the reduced input selection chart in High Alt. Instruction
Section.
To change orifice spuds for either conversion to LP or for elevation:
1. Shut off the manual main gas valve and remove the
gas manifold.
2. Replace the orifice spuds.
3. Reassemble in reverse order.
4. Turn the gas supply back on and check for proper operation and manifold pressure.
5. Attach the notice label alerting the next service technician that the furnace has been converted to LP gas.
FIGURE 21
TYPICAL LP KIT CONTENTS
!
WARNING
LP TANKS FROM LOCAL LP SUPPLIER MUST NOT
BE USED TO STORE ANYTHING (SUCH AS FERTILIZER) EXCEPT LP GAS. THIS INCLUDES ALL DELIVERY VESSELS (LP TRUCKS). IF MATERIAL OTHER
THAN LP GAS IS USED IN THE SAME
VESSELS/TANK AS THE LP GAS, THE LP GAS CAN
BECOME CONTAMINATED AND DAMAGE THE FURNACE. THIS WILL VOID THE MANUFACTURER’S
WARRANTY. CONTACT THE SUPPLIER TO MAKE
SURE FERTILIZER IS NOT USED IN THE SAME
TANKS USED TO STORE AND DELIVER LP GAS.
Page 28
28
Electrical Wiring
ELECTRICAL CONNECTIONS
Before proceeding with the electrical connections, be certain that
the voltage, frequency and phase corresponds to that specified
on the furnace rating plate. For single furnace application, maximum over-current protection is 15 amperes.
Use a separate fused branch electrical circuit containing a properly sized fuse or circuit breaker. Run this circuit directly from the
main switch box to an electrical disconnect that is readily accessible and located near the furnace (as required by code). Connect
from the electrical disconnect to the junction box on the left side
of the furnace, inside the blower compartment. For the proper
connection, refer to the appropriate wiring diagram located on the
inside cover of the furnace control box and in these instructions.
NOTE: The electrical junction box may be moved to the right side
if necessary. A knockout is provided. Seal the opposite hole with
plug provided.
NOTE: L1 (hot) and L2 (neutral) polarity must be observed when
making field connections to the furnace. The ignition control may
not sense flame if L1 and L2 are reversed. Make all electrical
connections in accordance with the latest edition of the National
Electrical Code ANSI/NFPA70.
These may be obtained from:
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, MA 02269
REVERSING THE ELECTRICAL
CONNECTION (JUNCTION BOX)
NOTE: Reversing the junction box is not possible in 14.0 inch
cabinets.
If the line voltage electrical needs to be moved to the opposite
side of the furnace, the following steps should be taken:
1. The furnace must NOT be electrically connected to line voltage prior to reversing the electrical connection.
2. Disconnect the wires from the door switch.
3. Remove the junction box from the furnace cabinet wall by removing the two screws that hold it to the cabinet. Leave the
wires connected to the junction box.
4. Remove 7/8” plug from hole opposite j-box location. Drill 2 @
3/16” Ø holes in the jacket. NOTE: Dimples/marks are provided in the sheet metal for correct drilling location.
5. Move the junction box to the opposite side of the cabinet. Install using the two screws removed in step 3 above. Note
that all screws penetrating the junction box must be blunt –
no sharp tipped screws can be used.
6. Replace the plug from the opposite of the furnace (the new jbox location) to the old j-box location and install qty=2 1/4”
plugs from parts bag in empty screw holes in old location of
j-box into the mounting screw holes in the old junction box location.
ELECTRICAL WIRING
ELECTRICAL WIRING
!
WARNING
THE CABINET MUST HAVE AN UNINTERRUPTED
GROUND ACCORDING TO THE LATEST EDITION OF
THE NATIONAL ELECTRICAL CODE, ANSI/NFPA70OR LOCAL CODES THAT APPLY. DO NOT USE GAS
PIPING AS AN ELECTRICAL GROUND. A GROUND
SCREW IS PROVIDED IN THE JUNCTION BOX. FAILURE TO DO SO CAN CAUSE ELECTRICAL SHOCK
RESULTING IN PERSONAL INJURY OR DEATH.
!
WARNING
THIS FURNACE IS EQUIPPED WITH A BLOWER
DOOR SAFETY SWITCH. DO NOT DISABLE THIS
SWITCH. FAILURE TO FOLLOW THIS WARNING
CAN RESULT IN ELECTRICAL SHOCK, PERSONAL
INJURY OR DEATH.
FIGURE 22
ST-A1220-05
!
WARNING
TURN OFF ELECTRIC POWER AT FUSE BOX OR
SERVICE PANEL BEFORE MAKING ANY ELECTRICAL CONNECTIONS. FAILURE TO DO SO CAN
CAUSE ELECTRICAL SHOCK RESULTING IN PERSONAL INJURY OR DEATH.
LOCKING
TABS
Page 29
29
ELECTRICAL WIRING
7. Using a flat screwdriver, squeeze the retaining arms on the
door switch and gently pry the door switch from it’s opening.
8. Install the door switch in the same opening on the opposite
of the furnace and reconnect the electrical connectors (removed in Step 2) to the door switch.
THERMOSTAT
See Thermostat Wiring Diagrams section for thermostat
connections. The room thermostat must be compatible
with the furnace. See manufacturer’s thermostat spec
sheet for compatability concerns. Generally, all thermostats that are not of the “current robbing” type are compatible with the integrated furnace control. The low voltage
wiring should be sized as shown.
NOTE: Do not use 24 volt control wiring smaller than No.
18 AWG.
Install the room thermostat in accordance with the instruction sheet packed in the box with the thermostat. Run the
thermostat lead wires inside the blower compartment and
connect to low voltage terminals as shown on the wiring diagram. Never install the thermostat on an outside wall or
where it will be influenced by drafts, concealed hot or cold
water pipes or ducts, lighting fixtures, radiation from fireplace, sun rays, lamps, televisions, radios or air streams
from registers.
REVERSING ELECTRICAL CONNECTION & THERMOSTAT
Electrical Wiring
ST-A1194-59-00
ST-A1194-60-00
FIGURE 23
ISOLATION RELAY
FIGURE 24
LINE VOLTAGE CONNECTIONS
Page 30
30
Accessories
ELECTRONIC AIR CLEANER
Line voltage power can be supplied from the terminal labeled
“EAC” and a line voltage neutral terminal on the control board.
This will power the electronic air cleaner whenever the circulating
air blower is in operation.
HUMIDIFIER
Humidifier output is a set of dry contacts. The logic controlling
these contacts and the necessary wire diagrams for installing a
humidifier are detailed in the section of this manual titled
Humidifi-
cation/Dehumidification
.
RXGW-C01 4-INCH FLUE ADAPTER
(See Figure 25)
Refer to “Venting” section of this manual for more information. See
National Fuel Gas Code for sizing options.
FILTERS (See Figure 26)
Keep filters clean at all times. A filter is not provided with the
furnace, but one must be field-supplied and installed.
It is recommended to replace the furnace filter periodically to
maintain optimum furnace performance.
RXGW-B01 CHIMNEY ADAPTER
IMPORTANT:
CHIMNEY ADAPTER IS CERTIFIED FOR USE
ON R802V MODELS.
This appliance is CSA certified for use with RXGW-B01 Chimney
Adapter. Refer to Kit Installation Instructions 92-101682-01.
TWINNING
Twinning of these furnaces is NOT permitted!
AIR TEMPERATURE SENSORS
Outdoor Air Temperature Kit RXGJ-J02
Supply Air Temperature Sensor 47-24225-01
Refer to supply and outdoor air temperature section of integrated furnace control for more information.
ACCESSORIES
FIELD INSTALLED OPTION ACCESSORIES
ST-A1220-27
FIGURE 25
1. STANDARD 3” FLUE CONNECTION
2. 4” ADAPTER OPTIONAL
SEE NATIONAL FUEL GAS CODE FOR SIZING OPTIONS
1. STANDARD3” FLUECONNECTION.
2. 4” ADAPTER
SEENATIONAL FUEL GAS CODE FOR SIZING OPTIONS
1.
2.
ST-A1220-27-00
Page 31
31
SIDE RETURN
BOTTOM RETURN
ST-A1220-07-00
FIGURE 26
FILTER LOCATIONS
ACCESSORIES
FIELD INSTALLED OPTION ACCESSORIES (cont.)
HORIZONTAL RETURN
ST-A1220-06-00
RXGF-CB ACCESSORY
FILTER RACK
FIELD SUPPLIED FILTER
Accessories
FLANGE WRAPS
AROUND BACK AND
SCREWS TO THE
REAR OF THE
FURNCE, AT THE
LOCATIONS
PROVIDED
CUT OUT USING
EMBOSSED ANGLES
ASA GUIDE
FORPROPERSIZE
23”X14”
FIELD SUPPLIEDFILTE R
RXGF-CD
ACCESSORY FILTE R RACK
ST-A1220-07-X0
RXGF-CB
$&&(6625<),/7(55$&.
FIELD SUPPLIED FILTER
ST-A1220-06-X0
Page 32
32
High Altitude
HIGH ALTITUDE
34" 80 Plus furnaces installed above 2,000 ft. require the furnace
to be de-rated 4% per thousand feet.
IMPORTANT:
Factory installed orifices are calculated and sized
based on a sea level Natural Gas heating value of 1050 BTU per
cubic ft.
NOTE: Orifices are available through your local distributor.
Reference Table 8 for approximate orifice sizing.
The following are examples of orifice sizing using the National
Fuel Gas Code Appendix F:
For a simplified estimation of orifice size based on gas heating
value and elevation, Table 8 may be used. However, calculations
are the best method.
Example: 900 BTU/ft
3
Regional Natural Gas Heating Value
I/H = Q
25000 / 900 = 27.78 ft
3
I = Sea Level input (per burner): 25000
H = Sea Level Heating Value: 900
Q = 27.78 ft3Natural Gas per hour.
From Table F.1 of
National Fuel Gas Code Handbook, 2002
(3.5ⴖ
w.c. column).
Orifice required at Sea Level: #40
From Table F.4 of
National Fuel Gas Code Handbook,
Orifice required at 5000 ft. elevation (4% de-rate per thousand ft): #42
Orifice required at 8000 ft. elevation (4% de-rate per thousand ft.):
#44
Example: 1050 BTU/ft3 Regional Natural Gas Heating Value
I / H = Q
25000 / 1050 = 23.81ft
3
I = Sea Level input (per burner): 25000
H = Sea Level Heating Value: 1050
Q = 23.81 ft3Natural Gas per hour.
From Table F.1 of
Natural Fuel Gas Code Handbook, 2002
(3.5⬙
w.c. column).
Orifice required at Sea Level: #43
From Table F.4 of
National Fuel Gas Code Handbook, 2002
Orifice required at 5000 ft. elevation (4% de-rate per
thousand ft.): #45
Orifice required at 8000 ft elevation (4% de-rate per
thousand ft): #47
ORIFICE ORDERING INFORMATION
Orifice sizes are selected by adding the 2-digit drill size required in
the orifice part number. Drill sizes available are 39 through 64;
metric sizes available 1.10mm (-90) and 1.15mm (-91):
Orifice Part Number 62-22175-(drill size)
Example 1:
# 60 drill size orifice required
Part # 62-22175-60
Example 2:
1.15mm drill size orifice required
Part # 62-22175-91
NATURAL GAS AT HIGH ALTITUDES
!
WARNING
INSTALLATION OF THIS FURNACE AT ALTITUDES ABOVE
2000 FT (610 m) SHALL BE IN ACCORDANCE WITH
LOCAL CODES, OR IN THE ABSENCE OF LOCAL CODES,
THE NATIONAL FUEL GAS CODE, ANSI Z223.1/NFPA 54.
!
CAUTION
ELEVATIONS ABOVE 2000 FT. REQUIRE THAT THE FURNACE INPUT RATING BE ADJUSTED AND THAT THE SIZE
OF THE BURNER ORIFICES BE RE-CALCULATED BASED
ON ELEVATION AND GAS HEATING VALUE. THE BURNER
ORIFICES MAY (OR MAY NOT) NEED TO BE CHANGED.
THE FOLLOWING EXAMPLES SHOW HOW TO DETERMINE IF AN ORIFICE CHANGE WILL BE NECESSARY
AND HOW TO DETERMINE THE NEW ORIFICE SIZE.
Page 33
33
TABLE 8
SUPPLEMENTAL ORIFICE SIZE CHART
HIGH ALTITUDE
NATURAL GAS AT HIGH ALTITUDES (cont.)
High Altitude
NATURAL GAS ORIFICE SELECTION BASED ON HEATING VALUE & ELEVATION*
Notes:
1. All (-)80+ units are factory equiped with orifices sized for 1050 sea level heating value gas.
2.
Installer must be aware of the local heating value (sea level standard) to use the chart below.
3. This chart is based on the National Fuel Gas Code (NFGC) Annex F based on natural gas with a secific gravity of 0.60
4.The recommended orificesbelow allow the furnace to operate within 10% of design rate. However, NFGC calculations are the best
method
.
5. Furnace operation is optimized when operating at design rate. Insta
6. This table applies to 80+ models only with 25,000BTU/Burner. DO NOT
Grey Cells Indicate Factory
Orifice Size
1,000-1,100
Gas Heating
Value
(BTU's/ft
@ Sea
Level**
*Table is derived from Appendix of the National Fuel Gas Code . To determine the correct orifice for your installation consult the National
Fuel Gas Code tables F.1 and F.4
**Be sure to use sea level heating value. When requesting the heating value from a local utility, it must be converted to sea level equivalent
in order to use this table.
Page 34
34
HIGH ALTITUDE
LP GAS AT HIGH ALTITUDES
LP GAS (TABLE 9)
NOTE: Keep any parts removed during LP conversion procedure
stored with the product literature for future use.
LP Gas is a manufactured gas that has consistent heating value
across most regions.
The NFGC guidelines are used with the following exception:
The recommended LP Gas high altitude orifice selections differ
slightly in that the NFGC LP orifice chart, as they are not accurate
for these products. The National Fuel Gas Code LP orifices are
based on an 11" of water column pressure at the orifice, which differs from products that use 10" of water column at the orifice. This
difference requires a deviation from the NFGC orifice size recommendations. The Sea Level input should still be reduced by 4%
per thousand ft. and the orifice size must be selected based on
the reduced input in Table 9.
LP GAS
IMPORTANT: 80+ MODELS ONLY! DO NOT
USE THIS CHART WITH ANY 90+ MODELS.
High Altitude
Page 35
35
Communicating Furnace
START-UP PROCEDURES
START-UP AND SEQUENCE OF OPERATIONS
This furnace is equipped with a direct ignition control. Each time
the room thermostat calls for heat, the ignitor lights the main
burners directly. See the lighting instructions on the furnace.
TO START THE FURNACE
1. Remove the burner compartment control access door.
2. IMPORTANT: Be sure that the manual gas control has been
in the “OFF” position for at least five minutes. Do not attempt
to manually light the main burners.
3. Turn off the furnace electrical power and set the room thermostat to its lowest setting.
4. Turn the gas control to the “ON” position or move the gas
control lever to the “On” position.
5. Replace the burner compartment control access door.
6. Turn on the furnace electrical power.
7. Set the room thermostat to a point above room temperature
to light the main burners. The heat call should be adequate
to activate the high stage gas heat – generally, the thermostat setpoint should be more than 2°F above room temperature. Consult your thermostat specs to be sure.
8. Operate high gas heat for a minimum period of 15 minutes
and adjust input rate (See Section of this book titled
Adjust-
ing Input Rate
).
9. Once high heat operation has been successfully verified and
rate adjusted, the thermostat should be adjusted to set the
heat call to low stage. This is generally with the heating setpoint at about 1°F above room temperature. Consult your
thermostat specs to be sure.
10. Operate low gas heat for a minimum period of 15 minutes
and adjust input rate (page 56).
TO SHUT DOWN THE FURNACE
1. Set the room thermostat to its lowest setting and wait for furnace to shut down.
2. Remove the burner compartment control access door.
3. Shut off the gas to the main burners by turning the gas control to the “OFF” position.
SEQUENCE OF OPERATION
HONEYWELL CONTROLS Integrated Controls
with Direct Spark Ignition.
1. Each time the thermostat “W” (Heating) contacts close
(legacy) or a communicating heat call is transmitted to the
furnace control from a communicating thermostat, the furnace control checks to make sure that both pressure
switches are open. This is true of a low or high heat call as
“W” is energized on either call. Next the induced draft
blower (inducer) begins a pre-purge cycle at high stage.
2. The air proving negative pressure switches (both low and
high) close. Inducer will then immediately shift to low speed.
3. After the 30-second pre-purge, the gas valve opens on low
stage for an 8-second trial for ignition.
4. The spark igniter is energized to light the gas burners and
stays energized for the up to 7 seconds after the gas
valve opens.
5. Eight seconds after the gas valve opens the remote flame
sensor must prove flame ignition for
one second
using
the process of flame rectification. If the burners don’t light,
the system goes through another ignition sequence. It does
this up to four times before entering a 1-hour lockout.
6. Twenty seconds after flame is sensed, the gas valve is set to
the thermostat demand (low or high) and the main blower
will be energized at either the low or high gas heat stage depending on the thermostat demand.
7. When the thermostat “W” (legacy) or communicated heat call
ends, the gas valve closes, flame is extinguished, the induced draft blower stops after a 10-second post-purge, and
the negative pressure switch opens.
8. The main blower continues until timed off by the setting on
the integrated furnace control board.
!
WARNING
SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY
FAIL TO SHUT OFF, CLOSE THE MANUAL GAS VALVE
FOR THE APPLIANCE BEFORE SHUTTING OFF THE
ELECTRICAL SUPPLY. FAILURE TO DO SO CAN CAUSE
AN EXPLOSION OR FIRE RESULTING IN PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
Page 36
36
Communicating Furnace
INTEGRATED FURNACE CONTROL
ST-A1194-51
FIGURE 27
R80V TWO-STAGE COMMUNICATING FURNACE CONTROL LAYOUT
TO MAIN (TWIST-LOCK)
4
5
8
6
3
S4
LOW VOLTAGE
RJ-11 COMMUNICATION CONNECTION
ION
T1
SPARK IGNIT
CONNECTION
(ALL MUST BE OFF)
BIAS/TERMINATION
DIPSWITHES(COMM ONLY)
TRANSFORMER
P2
P5
5-TERMINAL
CONNECTION
LOW VOLTAGE
7-TERMINAL
COMMUNICATIONS LED'S
LOW VOLTAGE
RECEIVE(RX)
TRANSMIT(TX)
CONNECTION
120 VAC TERMINALS
J1
2
P1
4-TERMINAL
WIRING HARNESS
7
(L1)
P3
INDUCER OUTPUT
NEUTRAL TERMINALS
S1
(NEUTRAL)
S2
S3
NEUTRAL FOR
9
ELECTRONIC AIR
CLEANER OUTPUT
T3
ELECTRONIC
AIR CLEANER OUTPUT
10
(DRY CONTACTS)
HUMIDIFIER RELAY OUT
P4
11
S1 S2 S3
CONNECTION
COMMUNICATIONS
CIRCULATION BLOWER
DIP SWITCH BANKS
P6
CONNECTOR
MEMORY CARD
U38
1
20
FUSE
P100/P101
E11
19
24VAC
(FROM XFMR)
24 VAC TO LOW
E10
24VAC
OF CONTROL
VOLTAGE SIDE
TRANSFORMER
SEC
(FROM XFMR)
T2
24VAC
INPUTS
THERMOSTAT
18
DUAL 7 SEGMENT
DIAGNOSTIC DISPLAY
OUTDOOR
LY
SUPP
AUX 1
CONNECTION
AUX 2
CONNECTION
T5
INPUTS
AUX 1 & AUX 2
COMMON FOR
AIR TEMPERATURE
AIR SENSOR INPUT
16
SENSOR INPUT
T4
S8
PUSH BUTTON
15141312
17
Page 37
37
1. P1 (4-Pin), P2 (7-Pin) and P5 (5-Pin) - Low-Voltage
Internal Wiring Connections – Connect main twist-
lock wire harness to these connections. Pre-wired
from the factory.
2. RJ-11 CONNECTOR (J1)
This connector is used to program the furnace control
at the factory. It should never be connected to a telephone line or a telephone. Doing so could damage the
furnace control or the telephone (or telephone lines)
or both.
3. SPARK IGNITION TRANSFORMER (T1)
The spark ignition transformer resides on the furnace
control. The transformer provides spark energy at approximately 60 hz frequency and a minimum of 12KV.
4. BIAS / TERMINATION (S4)
For current installations, all three of the dip-
switches in bank SW4 must be in the “OFF” position. If not, the system may not be able to
communicate.
5. COMMUNICATIONS LED’S (U38)
Two LED’s are provided to indicate the status of com-
munications. A red LED (Labeled TX) is provided for
transmit and a green LED (Labeled RX) is provided
for receive. These LED’s will be lit in an undefined
pattern when other communicating components are
attached and communicating with the furnace control.
6. LINE VOLTAGE CONNECTIONS (120VAC, L1)
Four ¼” Quick-Connect style terminals are provided
for internal connections and accessories.
7. INDUCED DRAFT MOTOR (INDUCER) OUTPUT
(P3)
This three-pin Mate-n-Lok style connector provides
power to both the high and low speed inducer outputs.
8. NEUTRAL TERMINALS (N)
Four ¼” Quick-Connect style terminals are provided
for internal connections and accessories.
9. ELECTRONIC AIR CLEANER (E.A.C.) OUTPUT (T3)
This output is used to energize an electronic air
cleaner. The output will provide 1.0 amp at 115 VAC.
This output is energized any time the blower motor is
above the airflow CFM values specified below. Airflow
below this value is not considered to be enough for a
typical electronic air cleaner to perform properly.
For ½ HP motors - Electronic air cleaner is energized
any time the blower is above 500 CFM
For ¾ HP motors - Electronic air cleaner is energized
any time the blower is above 600 CFM
For 1 HP motors - Electronic air cleaner is energized
any time the blower is above 700 CFM
Continuous fan speeds are selectable and some lower
fan speeds may not deliver enough airflow to operate
an electronic air cleaner. The IFC determines the minimum airflow necessary to operate an electronic air
cleaner and will not turn on the electronic air cleaner
unless the airflow is high enough for the EAC.
10. HUMIDIFICATION (T3) AND DEHUMIDIFICATION
HUMIDIFIER – The humidifier contacts (labeled
“HUM” (2)) are “dry” contacts on the I.F.C. This means
that the terminals are connected directly to the contacts of a board-mounted relay. The coil of the relay is
controlled by the microprocessor of the IFC. The coil
is engaged roughly any time the heat speed blower is
engaged and (1) 24VAC is present on the thermostat
terminal of the IFC labeled “HUM STAT” or (2) a communicating thermostat with humidification and dehumidification capability is installed with call for
humidification present. (See Figure 28 for location of
humidification/dehumidification inputs on furnace control.)
INTEGRATED FURNACE CONTROL
Communicating Furnace
!
WARNING
DO NOT CONNECT A TELEPHONE OR PHONE LINE
TO THE CONNECTOR (JACK) AT POSITION J-11.
DOING SO COULD CAUSE IRREPARABLE DAMAGE
TO EITHER THE FURNACE CONTROL (I.F.C.) OR
THE TELEPHONE (OR TELEPHONE LINE) OR
BOTH.
FIGURE 28
ELECTRONIC AIR CLEANER AND HUMIDIFIER TERMINALS
ST-A1194-64-00
Page 38
38
INTEGRATED FURNACE CONTROL
HUMIDIFICATION/DEHUMIDIFICATION
An optional 24VAC humidistat can be installed as
shown in Figures 29 thru 32. With the optional humidistat, two separate conditions must be met before humidification can begin 1). There must be a call for heat
and the blower must be engaged and 2.) The humidistat must determine that there is a need for humidification. Note: Dipswitch S2-8 (labeled “ODD”) enables
(“ON”) or disables (“OFF”) de-humidification operation. However, it has no affect on humidification operation. If this switch is set to the “ON” position and no
humidistat is installed, the cooling airflow will be permanently reduced by approximately 15% giving less
than optimal performance and possibly causing problems. It is not recommended to leave this switch in the
“ON” position without a humidistat installed.
Control of dehumidification in cooling and/or humidifi-
cation in heating can be done with a variety of methods depending on whether there is a communicating
thermostat or a humidistat available and depending on
the type of operation desired.
With systems configured with communicating thermo-
stats and condensers, dehumidification is controlled
by the thermostat and is not affected by the position of
dipswitch SW2-1 or the voltage at the thermostat input
T2 labeled “HUM STAT” on the furnace. To determine
which wiring diagram and method to use, select from
the following configurations:
A. HUMIDIFICATION CONTROL ONLY WITH NO
DEHUMIDIFICATION (REQUIRES OPTIONAL
HUMIDIFIER).
A1. WITH COMMUNICATING THERMOSTAT
Humidifier control is included with EcoNet
communicating thermostats. To wire the furnace for humidification control using an
EcoNet communicating thermostat, refer to
the wiring diagram in Figure 29. Be sure not
to install the jumper between “R” and “HUM
STAT” on the furnace control. Installing this
jumper will operate the humidifier any time
there is a heat call. Without the jumper, the
humidification call from the thermostat must
be active and a heat call must be present with
the blower running.
A2. WITH NON-COMMUNICATING THERMO-
STAT
A2-1 CONTINUOUS HUMIDIFIER OPERA-
TION DURING HEATING.
For continuous humidifier operation during
heating, refer to Figure 29 and make sure to
install the jumper between the thermostat terminals labeled “R” and “HUM STAT”. A separate humidistat is not required for this
configuration and the humidifier will turn on
whenever there is a call for heat and the
blower is running.
A2-2 CONTROLLED HUMIDIFIER OPERATION USING A HUMIDISTAT (REQUIRES
OPTIONAL HUMIDISTAT).
Controlled humidification can be accomplished using a humidistat as shown in Figures 30 or 31. These figures show installation
of a humidifier with external and internal
power supplies respectively. Dehumidification
operation will be disabled if the dipswitch S2-8
is in the “OFF” position. If this switch is in the
“ON” position, dehumidification control will be
active.
B. DEHUMIDIFICATION CONTROL WITH NO HU-
MIDIFICATION
B1. WITH COMMUNICATING THERMOSTAT
For communicating thermostats listed with this
furnace, dehumidification is controlled automatically when selected at the thermostat and
additional wiring is not necessary. The actual
airflow demand (reduced for dehumidification)
is requested of the furnace by the thermostat.
B2. WITH NON-COMMUNICATING THERMO-
STAT (REQUIRES OPTIONAL HUMIDISTAT)
Control of dehumidification only (no humidification) can be accomplished by installing an
optional humidistat as shown in Figure 32.
The dipswitch S2-8 must be set to the “ON”
position. If this switch is not turned “ON”, dehumidification operation will not take place.
Further, if this switch is “ON” and no humidistat is installed, airflow in cooling will be permanently reduced by approximately 15%.
C. HUMIDIFICATION AND DE-HUMIDIFICATION
CONTROL (REQUIRES OPTIONAL HUMIDIFIER).
C1. WITH COMMUNICATING THERMOSTAT
Humidifier control is included with EcoNet
communicating thermostats. To wire the furnace for humidification and dehumidification
control using an EcoNet communicating thermostat, refer to the wiring diagram in Figure
29 Option A. Be sure not to install the jumper
between “R” and “HUM STAT” on the furnace
control. Installing this jumper, as in Figure 29
Option B, will operate the humidifier any time
there is a heat call and dehumidification will
never take place when in cooling. Without the
jumper, a humidification call from the thermostat must be active and a heat call must be
present with the blower running for the “HUM”
relay contacts to close.
Communicating Furnace
Page 39
39
HUMIDIFICATION/DEHUMIDIFICATION
C2. WITH NON-COMMUNICATING THERMO-
STAT (REQUIRES OPTIONAL HUMIDISTAT)
For non-communicating thermostats, an optional humidistat must be installed. Controlled
humidification and dehumidification can be accomplished using a humidistat as shown in
Figures 30 or 31. These figures show installation of a humidifier with external and internal
power supplies respectively. Dehumidification
operation will be disabled if the dipswitch S2-8
is in the “OFF” position. If this switch is in the
“ON” position, dehumidification control will be
active.
INTEGRATED FURNACE CONTROL
Communicating Furnace
T
FIGURE 29
WIRING FOR OPTIONAL HUMIDIFICATION (AND DE-HUMIDIFICATION WITH COMMUNICATING THERMOSTAT) WITH OPTIONAL
HUMIDIFIER AND NO HUMIDISTAT (HUMIDIFICATION ACTIVE DURING ANY HEAT CALL)
(FOR USE WITH COMMUNICATING OR NON-COMMUNICATING THERMOSTATS)
ST-A1194-55-01
FIGURE 30
WIRING FOR OPTIONAL DE-HUMIDIFICATION AND HUMIDIFICATION (WITH OPTIONAL HUMIDISTAT AND HUMIDIFIER).
NOTE: CAN BE USED WITH COMMUNICATING OR NON-COMMUNICATING SYSTEMS.
ST-A1194-56-00
FIELD INSTALLED JUMPER
FROM “R” TO “HUM STAT”
ERMINALS OPTION:
A. DO NOT INSTALL JUMPER
- THERMOSTAT CONTROLS
HUM/DEHUMIDIFIER.
B. INSTALL JUMPER
- ACTIVATES HUM ON
HEAT CALL. DOES NOT
CONTROL DEHUMIDIFIER.
NEUTRAL OR COMMON
110V OR 24V
POWER SUPPLY
AS NECESSARY
FOR HUMIDIFIER
HUMIDIFIER WITH
EXTERNAL 110V OR
24V POWER SUPPLY
Page 40
40
11. COMMUNICATING ECM MOTOR COMMUNICATIONS (CONTROL) CONNECTION (P4)
This connector sends and receives messages to and
from the blower motor through a single peer-to-peer
network. The blower motor does not communicate on
the same communications buss as the furnace, condenser (or heat-pump) and thermostat. Further, a different communications protocol is used.
12. DIPSWITCHES; S1, S2 AND S3
NOTES:
1. There is a protective cover over the dipswitches
that must be penetrated to change the dipswitch
position. Use a pen or similar tool to penetrate the
cover and change the position. This is normal and
penetration of the protective cover will not damage
the dipswitch.
INTEGRATED FURNACE CONTROL
HUMIDIFICATION/DEHUMIDIFICATION
Communicating Furnace
FIGURE 31
WIRING FOR OPTIONAL DE-HUMIDIFICATION AND HUMIDIFICATION WITH OPTIONAL HUMIDIFIER (HUMIDIFIER WITH INTERNAL
POWER SUPPLY). NOTE: FOR USE WITH NON-COMMUNICATING SYSTEMS.
ST-A1194-57-00
FIGURE 32
HUMIDISTAT USED TO CONTROL DEHUMIDIFICATION IN COOLING ONLY (NO HUMIDIFIER)
NOTE: FOR USE WITH NON-COMMUNICATING THERMOSTATS.
ST-A1194-58-00
Page 41
41
INTEGRATED FURNACE CONTROL DIPSWITCHES
Communicating Furnace
FIGURE 33
DIPSWITCH MAP
ST-A1210-03
-7°
+ 7°
+12°
˜
˜
˜
J
K/L
I
H
G
Switch 9
1st Stage Compressor Airflow (TDM)
F
E
2000
1600
1400
1200
D
800
1000
600
of full airflow.
Low airflow is 75% of full airflow with
is in the ON position, low airflow is 50%
switch 9 in the OFF position. If Switch 9
1200
C
B
A
Page 42
42
INTEGRATED FURNACE CONTROL
DIPSWITCHES
2. For communicating systems, dipswitches are not
used. Configuration changes are made with the
thermostat.
A. Seven-Segment Display Orientation; S1-1
As the control will be applied in a multi-position furnace a means of changing the orientation of the
seven segment display is provided. This dipswitch
is to be labeled S1-1. Factory setting of the S1-1
dipswitch is OFF.
S1-1 = OFF = Upflow (as-shipped) position
S1-1 = ON = Downflow position
B. Cool Blower-Off Delay; S1-2 & S1-3
A means of selecting the cooling speed blower “off”
delay time is provided. In legacy mode, dipswitches are required to select the delay time.
These dipswitches are to be labeled S1-2 and S1-
S1-4 and S1-5 are to be used to select cooling airflow in legacy mode. The value used for each selection is specified below.
HIGH COOL SELECTIONS:
½ HP Blower
S1-4S1-550 + 75 BTU¾ HP Blower
(17” Cabinet)R802VA075417100 + 125
OFF OFF 1200 CFM1600 CFM2000 CFM
(Factory Setting)
ONOFF 1000 CFM1400 CFM1600 CFM
OFF ON 800 CFM1200 CFM1400 CFM
ONON 600 CFM1000 CFM1200 CFM
LOW COOL SELECTIONS:
The following model data fields are multipliers to be used
for low stage legacy cooling unless dipswitch S2-9 is in
the ON position - in which case the low cooling airflow becomes 50% of the high cooling airflow.
½ HP Blower
S1-4S1-550 + 75 BTU¾ HP Blower
(17” Cabinet)R802VA075417100 + 125
OFF OFF 900 CFM1200 CFM1500 CFM
(Factory Setting)
ONOFF 750 CFM1050 CFM1200 CFM
OFF ON 600 CFM900 CFM1050 CFM
ONON 450 CFM750 CFM900 CFM
Airflow dipswitches are to be used to determine airflow
when a legacy (24 VAC) call is placed on the thermostat
inputs of the control. Communicated calls will have CFM
requirements as part of the call (when a legacy condenser
is attached to a communicating furnace the airflow demand will be transmitted from the communicating thermostat as the installer will configure the cooling airflow
requirements for the non-communicating condenser at the
thermostat and the airflow requirements for the condenser
will be stored at and transmitted from the thermostat).
D. Cooling/Heat Pump Airflow Trim; S1-6 & S2-7
Two dipswitches (S1-6, S2-7) are to be provided
for legacy cool airflow trim. The value used for
each selection is specified below. Two of these values are taken from the furnace Model Data file.
Selections are as follows:
S1-6S2-7Description
OFFOFFNo Adjust. (Factory Setting)
ON OFF+10%
OFFON-10%
ONONNo Adjust.
E. ODD (On Demand Dehumidification); S2-8
One dipswitch (S2-8) is to be provided to enable
the dehumidification feature in legacy mode. Selections are as follows:
S2-8=OFFODD not enabled.
(Factory Setting)
S2-8=ONODD enabled. 0VAC on
“HUM STAT” will decrease
airflow in cooling.
F. Tandem Airflow Select; S2-9
One dipswitch (S2-9) shall be used to select the
percentage of airflow for the base first stage cooling airflow in legacy mode. Note that further adjustments may also be applied (e.g. for active
dehumidification or cooling airflow trim).
Communicating Furnace
Page 43
43
INTEGRATED FURNACE CONTROL
DIPSWITCHES
Low Cool % of 2
nd
S2-9Stage Cooling Airflow
ON 50%
OFF75%
OFF is Factory Setting
G. Auto Stage; S2-10 & S2-11
There are applications where a single stage thermostat is used with the two stage furnace. With
these applications the furnace will initially operate
in the low heat stage. Based upon a user selected
time, the furnace will automatically stage to high
heat stage mode. Auto staging will take place with
a 24VAC signal on “W1” when autostaging is
turned on. “W2” will be recognized as a call for
stage 2 heat even when autostaging is active. The
following dipswitches are available to accommodate this requirement:
S2-10S2-11 AutoStage
OFFOFFNormal 2 stage operation
(Autostaging is off)(factory set-
ting)
ONOFFAutoStage, 10 minutes on low,
then to high with call on “W1”
OFFONAutoStage, 15 minutes on low,
then to high with call on “W1”
ONONAutoStage, 20 minutes on low,
then to high with call on W1”
H. Continuous Fan Speed; S2-12
One dipswitch (S2-12) is to be provided for legacy
continuous fan adjustment.
Selections are as follows:
S2-12 =OFF = 500 CFM for ½ HP, 700 for 3/4HP,
800 CFM for 1 HP motors. (factory setting)
S2-12 =ON = 800 CFM for ½ HP,
1200 for 3/4HP, 1600 CFM for 1 HP motors.
I. Low Gas Heat Rise (Airflow) Adjustment; S3-13,
S3-14
Two dipswitches (S3-13, S3-14) shall be used to
select low (1
st
stage) gas heat rise airflow adjustment in legacy mode. Each selection will use a different airflow demand for first stage gas heat. The
selections are set to approximate a specified temperature rise as follows. Note: Temperature rise
will vary based on conditions and technician
should always check temperature rise.
S3-13
S3-14 Target Temperature Rise
OFFOFFNominal Value Specified on Rating
Label (Factory Setting) (Approx.)
ONOFFApprox. +7°F
OFFONDo not use
ONONApprox. +12°F
J. High Gas Heat Rise (Airflow) Adjustment; S3-
15, S3-16
Two dipswitches (S3-15, S3-16) shall be used to
select high (2nd stage) gas heat rise airflow adjustment in legacy mode. Each selection will use a different airflow demand for second stage gas heat.
The selections are set to approximate a specified
temperature rise as follows. Note: Temperature
rise will vary based on conditions and technician
should always check temperature rise.
S3-15 S3-16 Target Temperature Rise
OFFOFFNominal Value Specified on Rating
Label (Factory Setting) (Approx.)
ONOFFApprox. +7°F
OFFONDo not use
ONONApprox. +12°F
K. Heat Blower Off Delay; S3-17, S3-18
Two dipswitches (S3-17, S3-18) can be used to select heat blower off delays (in seconds) in legacy
mode.
S3-17 S3-18 Heat OFF Delay (high & low)
OFFOFF90 (Factory Setting)
ONOFF120
OFFON160
ONON180
L. Manual Fault Clear
Dipswitch S3-18 also doubles as a means to clear
the fault history buffer. The switch can be turned
off/on/off/on/off/on (three times) or
on/off/on/off/on/off (three times) within less than 30
seconds and the fault buffer will be cleared.
Communicating Furnace
Page 44
44
Communicating Furnace
INTEGRATED FURNACE CONTROL
MODEL DATA CARD & DUAL SEVEN-SEGMENT DISPLAY
13. MODEL DATA CARD CONNECTOR (P6)
There is a factory-installed model data card which is
wire-tied to the furnace. At no time should this card be
removed from the furnace except during replacement
of the control.
MODEL DATA CARD
A model data card is defined as an electronic card that
carries a copy of the furnace model data.
The furnace control receives model-specific data from
the model data card.
Replacement model data cards with the appropriate furnace model data for any given model can be ordered from
the Replacement Parts Division. In the event that the original model data card is lost, the original furnace control has
been replaced and there is no furnace model data, the replacement model data card must be ordered and installed
into the connector at P6 to give the furnace valid furnace
model data. The furnace will not operate properly without
the correct furnace model data. When no furnace model
data is present either at the memory or on the furnace microprocessor a “d1” (NO MODEL DATA) fault code will be
displayed at both the thermostat active fault screen and at
the furnace control (I.F.C.) seven-segment displays.
If the original model data card is lost, it should be replaced
even if there is valid furnace model data on the IFC microprocessor. The valid furnace model data on the IFC microprocessor should only be considered as a backup to
the model data card.
14. DUAL SEVEN-SEGMENT DISPLAY AND FAULT
CODES (U38)
NOTE: Verify display orientation is correct before in-
terpreting fault codes. Otherwise the fault codes may
be upside down.
A dual seven segment display shall be provided to dis-
play status and diagnostic code information. A fault
level 1 is a low-level fault. In general, a level 2 fault is
a fault that is severe enough that it prevents furnace
or other critical (e.g. cooling) operation. Level 1 faults
generally permit operation to continue but operation
may not be at optimum performance (e.g. blower operating at power maximum). Standard operating
codes (e.g. C for high-stage cooling) are considered
fault level “0” as they are not faults at all but only indications of current modes of operation which are considered normal (some operational codes are displayed
simultaneously with low level faults which do not interrupt operation - see paragraphs below for details).
Since usually only one fault can be displayed at the
seven-segment display at any given time (see exceptions below), the fault displayed when two or more
faults are present at the same time shall be resolved
by the fault code list below which calls out the fault
code priority. Lower numbers are considered higher
priority than larger numbers. Therefore, fault code priority 0 has the highest priority and shall be displayed
when present regardless of any other fault that might
also be present at the same time. This mechanism
does not prevent simultaneous faults from being
logged into the fault code buffer.
The mode displays for heat mode (“h” “H”) shall reflect
the demand from the thermostat. This includes when
only a first stage heat call; “W1” is present (“W2” not
present), the mode displayed should reflect the first
stage demand by displaying the lower-case “h” and
not the actual output of the furnace during ignition
(since this configuration ignites at high stage).
Three exceptions to this rule exist as follows:
1. When the thermostat demand is for high stage and
only low heat can be provided because the high
pressure switch will not close or has opened and
will not re-close. In this case, the mode “h” (low
heat) shall be displayed alternately along with the
fault
“57”
(open high pressure switch) (See item 5
below in this section).
2. When autostaging has been activated and a response to “W1” heat has been increased to high
heat by the furnace control after the user-specified
time even though a call for high heat (“W2”) is not
present. In this case a capital “H” shall be displayed and not a lower-case “h”.
!
WARNING
DO NOT REPLACE THE FURNACE CONTROL OR
MODEL DATA CARD OF THE FURNACE WITH A FURNACE CONTROL OR MODEL DATA CARD OF ANOTHER FURNACE OR ANOTHER COMPONENT
(E.G.: A MODEL DATA CARD FROM A CONDENSER
OR AIR HANDLER). THE WRONG FURNACE CONTROL OR MODEL DATA CARD MAY SPECIFY PARAMETERS WHICH WILL MAKE THE FURNACE RUN
AT UNDESIRED CONDITIONS INCLUDING (BUT NOT
NECESSARILY LIMITED TO) REDUCED AIRFLOW
DURING HEATING CAUSING EXCESSIVE UNDESIRED OPERATION OF THE MAIN LIMIT CONTROL.
FURTHER, THE MODEL DATA CARD IS SPECIFIC TO
THE MODEL NUMBER AND BTU INPUT RATING FOR
A SPECIFIC FURNACE AND THIS INFORMATION
SHOULD NOT BE TRANSPORTED FROM ONE FURNACE (OR COMPONENT) TO ANOTHER.
Page 45
45
Communicating Furnace
INTEGRATED FURNACE CONTROL
DUAL SEVEN-SEGMENT DISPLAY
3. When the furnace is in a heat or cool blower off
elay, the display should be “0”.
A standard operating code (with fault level “0”) shall
be displayed steady-on.
When displaying a fault code, it shall be flashed
and not be displayed steady-on. It shall be flashed
on for one second, then off for ½ second then on
again. Cycle repeats until the fault is cleared. Each
fault is flashed (displayed) a minimum of two times
even if the fault condition has cleared before the
fault can be displayed twice.
Dual Faults Displayed
Normally only one fault or status character is displayed at
the Seven-segment display at any given time. Exceptions
for some dual faults are noted below.
Sequence of display:
A. The first fault will be displayed for one second
B. The upper-most horizontal segment of the right
seven-segment display is energized for ½ second
C. The second fault is displayed for one second
D. The upper-most horizontal segment of the right
seven-segment display is energized for ½ again.
This cycle repeats until one or both faults are gone or otherwise as noted below:
1. When both low pressure switch and high pressure
switch are open and both should be closed fault
codes
“45”
and
“57”
will be displayed alternately
as described above (A-D).
2. When a failed ignition has occurred four times in a
row, the control enters one-hour lockout and fault
codes
“10”
and
“11”
will be displayed alternately
as described above (A-D).
3. When flame is lost five times in a row, the control
enters one-hour lockout and fault codes “10” and
“13”
will be displayed alternately as described
above (A-D).
4. When both the low pressure switch and high pressure switch are closed and both should be open (as
in during the pressure switch proving period). In
this case fault codes
“44”
and
“55
” will be dis-
played alternately as described above (A-D).
5. When the high pressure switch is open and the demand from the thermostat is set to 100% heat. . . In
this case the operation code “h” (for low heat) and
the fault code
“57”
(open high pressure switch) will
be displayed alternately.
6. While the control is in one-hour lockout due to an
unexpected flame, the fault codes
“14”
(unex-
pected flame) and
“10”
(soft lockout) will be displayed alternately as described above (A-D).
NOTE: Fault code 10 will not be displayed until
after fault has cleared.
7. While the control has entered a one-hour lockout
after declaring a dead blower after the main limit
control has been open for more than 150 seconds,
the fault codes
“61”
(Non-operational blower) and
“10”
(soft lockout) will be displayed alternately as
described above (A-D). Note: the dead blower fault
and associated one-hour lockout will occur up to
four times in one heat call. Upon declaring this fault
for the fourth time in one heat call, the control will
enter hard lockout.
8. When the main limit has been open during a gas
heat call for more than 150 seconds and has not
yet re-closed, the fault codes
“61”
(Non-operational
blower) and
“22”
(open limit) will be displayed alternately as described above (A-D) until the limit recloses.
9. When IFC is in soft lockout and fault
“93”
is active,
the fault code
“93”
is to be displayed alternately
with the fault code
“10”
.
10. When gas valve is open, flame is sensed and IFC
detects a fault condition which will not prevent gas
heating operation from continuing (like fault “57”,
“12”, “66”
,…) , IFC will display the operation code
“h”
or
“H”
alternately with the active fault code.
Page 46
46
Communicating Furnace
INTEGRATED FURNACE CONTROL
DUAL SEVEN-SEGMENT DISPLAY
The fault and mode codes and fault priorities are listed below. Priority is to be used to determine which fault to display
when two or more faults are present simultaneously.
NOTE:
Verify display orientation is correct before interpreting fault
codes. Otherwise the
fault codes may be
upside-down. If a
fault code is not on
this list, the display
may be upside down.
30
93
d1
68
61
26
58
14
33
23
22
10
44
45
46
55
57
11
13
66
60
12
H
h
C
c
cd
Cd
hP
HP
dF
F
82
84
81
d4
d6
0
99
Circuit Open P41-P42 (should be filtered)
Page 47
47
INTEGRATED FURNACE CONTROL
PUSHBUTTON
15. PUSHBUTTON (S8)
The status mode is entered when the pushbutton is
pressed for less than 2 seconds. While in the Status
menu at the seven segment displays, the category
field is displayed first for one second immediately followed by the appropriate value for one second. This
cycle repeats until 60 seconds has expired or the
pushbutton as been pushed again for less than two
seconds. If the button is pressed again for less than 2
seconds within the 60 second period, the next field will
be displayed and the 60 second timer will be reset.
After displaying all of the categories listed, the control
will loop back to the first category when the button is
pressed again for less than 2 seconds.
If within the status menu, if the button is pressed for
more than 2 seconds but less than 5 seconds, the display will exit the status menu upon release of the
push-button. Otherwise, the status menu will automatically exit if no activity is sensed on the pushbutton for
60 seconds.
The categories will be displayed in the following se-
quence:
CategoryInformation
FLUp to six faults (Example: —d1-14-26—)
AFIBM CFM
(Example: 1251 = 12-51, 745 = 7-45)
FrFire rate % (Example: 70)
UIFurnace size
trTemperature Rise in Degrees F
(example 75)*
*If the Supply air temp sensor is not available the cat-
egory will not be displayed.
Fault history display (FL)
Up to 6 faults are stored in the buffer with the most recent
replacing the oldest fault.
Unless otherwise specified, when a fault becomes active it
is to be stored in non-volatile memory provided no more
than three occurrences of any given fault code are already
stored in the fault buffer. If a fault occurs and there are already 3 occurrences of the same fault in the buffer, the
current fault will replace the oldest of the same fault in the
buffer but will become the most recent fault displayed.
Before updating the fault history the history will be examined for the previous most recent record. If the most recent record in the history is the same fault number but has
a lower fault level than the new fault, then instead of
adding the new fault to the buffer, the previous fault and
level are replaced with the new fault and level. The time
stamp will also be updated. This way, the existing fault will
be updated but a new fault will not be added.
Faults older than 168 powered hours will be automatically
deleted from the fault buffer.
When fault recall is activated, the six most recent faults
which have occurred within 1 week (168 powered hours)
will be displayed on the seven segment display in succession from the most recent to the oldest.
When displaying fault codes stored in the buffer, the control will flash the A and D segments of the least most significant SSD for ½ second to indicate the beginning of the
fault recall. Each fault shall be displayed steady for one
second followed by energizing the top segment (A or D
depending on the position of the Display Orientation Dipswitch) of the least significant (right most) Seven-segment
display for ½ second followed by the next fault displayed
for one second. This cycle repeats until all faults in the
buffer are displayed. After all of the faults are displayed,
the control will again energize the A and D segment of the
least significant S.S.D. for ½ second.
Airflow Display (AF)
Displayed CFM range is between 100 and 9999 per following sequence:
The sequence repeats until the status menu is exited or
the pushbutton is pressed again.
Fire Rate Display (Fr)
Gas heat fire rate is displayed for 1 second as follows:
“0”
is displayed when flame is not lit.
“HI”
is displayed when flame is lit and the fire rate is high.
“Lo”
is displayed when flame is lit and the fire rate is low.
Model BTU Capacity/1000 (Unit Input) (UI)
The furnace input BTU will be taken from the model data
field
Furnace BTU’s/1000
. Values less than 100 will be
displayed as two digits (example 70 displayed as 70). Values of 100 or greater will be displayed as three digits. The
most significant digit will be displayed for one second on
the left SSD followed by the remaining two digits which
are also displayed for one second. Example: 112 would be
displayed as 1 followed by 17.
Temperature Rise (tr)
Temperature rise is to be displayed (Supply Temp – Return Temp). If the Supply air temp sensor is not available
the category will not be displayed.
The fault buffer can be cleared with the pushbutton while
the Fault History Display (FL) menu is active by holding
down the pushbutton for 5 seconds or more. For indication
that the fault buffer is clear the IFC will flash segments A
and D of the right-most seven segment displays one second on and one second off three times after the fault clear
command has been recognized.
Extended Display Mode
If the pushbutton is pressed during the power-up sequence, IFC will turn on the extended display mode. The
extended display mode modifies the display operation per
the following table:
EXTENDED DISPLAY MODE – DISPLAY PROPERTIES
Page 49
Communicating Furnace
INTEGRATED FURNACE CONTROL
SUPPLY & OUTDOOR AIR TEMPERATURE SENSORS
16. SUPPLY AND OUTDOOR AIR TEMPERATURE
SENSOR INPUTS (T4)
Optional field installed supply air SA1, SA2 outdoor air
sensors (10K NTC thermistor) shall be read from the
T4 screw terminal block.
Control to resolve temperature within +/-2°F at 70°F
There is to be an automatic detection of the supply
and outdoor air sensors. If the resistance between the
terminals is within a valid 10K thermistor range (supply air temp range = -40°F to 200°F, outdoor air temp
range = -40 to 200°F), both sensors temperatures will
be accessible.
If the resistance between the supply air terminals is
determined to be out of range to a high resistance, it
shall be interpreted as an uninstalled supplied air sensor and shall not cause an error condition unless a
valid thermistor value was previously sensed on the
same power cycle. If the sensor was determined to be
present and then is opened the control should display
a fault “82”. The fault is a level 1 fault and will not inhibit furnace operation. Also, if the resistance between
the terminals is determined to be out of range to a low
resistance and a valid thermistor value was sensed on
the same power cycle, a fault “82” is to be displayed
on the seven segment displays.
If the resistance between the outdoor air terminals
(OAT) is determined to be out of range to a high resistance, it shall be interpreted as an uninstalled supplied outdoor air sensor and shall not cause an error
condition unless a valid thermistor value was previously sensed on the same power cycle. If the sensor
was determined to be present and then is opened the
control should display a fault “84”. The fault is a level
1 fault and will not inhibit furnace operation.
Also, if the resistance between the terminals on the
OAT is determined to be out of range to a low resistance, a fault “84” is to be displayed on the seven segment displays only if a valid thermistor value was
previously sensed on the same power cycle.
Fault codes
“82”
and
“84”
shall only be present for
three minutes after the fault is detected. After three
minutes has expired, the fault will no longer be set
even if the condition creating the fault is still present.
These faults are also only logged into the fault buffer
one time. Should the sensor error later clear and then
appear again the same sequence as noted previously
will be repeated.
FIGURE 34
WIRING OF SUPPLY AIR (SA) AND OUTDOOR AIR (OAT) TEMPERATURE SENSORS.
ST-A1194-63 (BOTTOM)
49
Page 50
50
Communicating Furnace
INTEGRATED FURNACE CONTROL
AUXILIARY INPUTS
17. AUXILIARY INPUTS (COMMUNICATING SYSTEMS
ONLY) (T5) (SEE FIGURE 35)
Terminal T5 is porovided for field installation of up to
two auxiliary switches. The auxiliary inputs shall be
used to provide a means of using traditional drain pan
switches, smoke detectors, freeze switches, etc. The
inputs are to be labeled
Aux 1
and
Aux 2
. The switch
inputs are for communicating systems only. One or
both inputs can be configured at the communicating
thermostat as either normally-opened or normally
closed contacts. System operation when the contacts
either open or close can be configured at the communicating thermostat.
A resistance of greater than 1k ohms to common shall
be detected as an open switch and a resistance of
less than 100 ohms shall be recognized as a closed
switch.
FIGURE 35
WIRING OF AUXILIARY INPUTS (USE WITH COMMUNICATING SYSTEMS ONLY).
Both communicating and legacy thermostats are to be
connected at terminal block T2.
A. COMMUNICATING SYSTEMS
The furnace is capable of communicating with a
thermostat and condenser to improve cooling and
heat-pump airflow, displaying active faults and active furnace information at the thermostat and improved diagnostics and troubleshooting.
WIRING A FURNACE FOR COMMUNICATIONS.
Maximum wire lengths and notes about wiring communicating systemsare noted below.
MAXIMUM COMMUNICATING WIRE LENGTHS
(E1, E2, R & C)
Max Wire Length – Thermostat to Furnace = 125 FT @ 18 AWG*
Max Wire Length – Furnace to Condenser = 125 FT @ 18 AWG*
Max Wire Length – Between any 2 devices = 125 FT @ 18 AWG*
Sum Max Total Wire Length for All Components = 500 ft
(see Figure 36)
Notes:
1. Wires may be solid or stranded.
2. *Wire gage smaller than 18 AWG is not approved or
recommended for this application.
3. If the thermostat wiring will be located near or in parallel with high voltage wiring, cable TV, Ethernet wiring,
or radio frequency equipment, then shielded thermostat wire can be used to reduce or eliminate potential
interference. The shielding must be contiguous (have
continuity) across all devices and all wire segments.
This should be done by twisting the shielding wires
from adjacent segments together. Further, the shielding for the entire system must be grounded in a single
location. Multiple grounds on the shielding system are
NOT permitted. The shield wire should be connected
to the C terminal, or ground, at the indoor unit. The
shield wire should NOT be connected to any terminal
at the Control Center (aka;Thermostat). Connecting
the shield to ground at both ends can cause current
loops in the shield, reducing shield effectiveness.
4. When using existing wire from a previous installation,
be sure to trim the tip of the wire back past the insulation and strip a small amount of insulation from the
wire to expose clean new copper for the communicating connections. Fresh copper must be exposed when
making the communicating connections or communications may not be properly established.
A. WIRING OF FULLY COMMUNICATING SYSTEMS.
Page 52
52
FIGURE 37
WIRING DIAGRAM FOR NON-COMMUNICATING CONDENSOR UNIT WITH COMMUNICATING FURNACE AND THERMOSTAT.
ST-A1194-54-03
Integrated Furnace Control
INTEGRATED FURNACE CONTROL
Figure 36 is the wiring diagram for connecting the furnace
to an approved EcoNet communicating thermostat and approved EcoNet communicating condenser. The only approved configuration is to install dedicated wires directly
from the furnace to the thermostat and a separate set of
dedicated wires directly from the furnace to the condenser.
Additional EcoNet devices can be added to the system as
shown in Figure 36. The approved wiring configuration is
the daisy-chain configuration shown in Figure 36. A star
wiring configuration is not approved and should not be
used.
Note: The only approved configuration requires that four
dedicated wires (E1,E 2, R and C) be installed from the
furnace to the condenser.
B.SPECIAL CONFIGURATION – WIRING OF
NON COMMUNICATING CONDENSORS
WITH COMMUNICATING FURNACE AND
THERMOSTAT (SEE FIGURE 37).
THERMOSTAT WIRING DIAGRAMS-CONDENSING UNIT
(NON-COMMUNICATING)
COMMUNICATING THERMOSTAT AND FURNACE
WITH NON-COMMUNICATING CONDENSER
(SINGLE - STAGE ONLY CONDENSER)
COMMUNICATING THERMOSTAT
EcoNet
(CONTROL CENTER)
NON-COMMUNICATING
CONDENSER UNIT
A. WIRING DIAGRAM
SPECIAL CONFIGURATION:
125 FEET MAX. @ 18 GA.
E1
E2
R
C
C
Y1
1
2
R
C
HUM STAT
W1
W2
G
Y1
Y2
B
SA2 OAT1
SA1
S1
S2
OAT2
S3
HUM
O
HUM EAC
NEUTRAL
L1
B. WIRING DIAGRAM
SPECIAL CONFIGURATION:
COMMUNICATING THERMOSTAT AND FURNACE
WITH NON-COMMUNICATING CONDENSER
(TWO - STAGE ONLY CONDENSER)
125 FEET MAX. @ 18 GA.
COMMUNICATING THERMOSTAT
EcoNet
(CONTROL CENTER)
E1
E2
R
C
NON-COMMUNICATING
CONDENSER UNIT
1
2
R
C
HUM STAT
W1
W2
C
Y1
Y2
TWO-STAGE
CONDENSER ONLY
G
Y1
Y2
B
S1
S2
SA2 OAT1
SA1
OAT2
S3
O
HUM
HUM EAC
NEUTRAL
L1
Page 53
53
FIGURE 38
WIRING DIAGRAM FOR A LEGACY SINGLE-STAGE THERMOSTAT WITH AUTOSTAGING.
ST-A1194-61-04
Integrated Furnace Control
INTEGRATED FURNACE CONTROL
C. SYSTEMS WITH LEGACY (NON-COMMUNICAT-
ING) THERMOSTATS
C1. WIRING OF A 1-STAGE LEGACY THERMO-
STAT WITH AUTOSTAGING SELECTED
(SEE FIGURE 38).
C2. WIRING OF A 2-STAGE LEGACY THERMO-
STAT (SEE FIGURE 39)
THERMOSTAT WIRING DIAGRAMS-CONDENSING UNIT
(NON-COMMUNICATING)
SINGLE-STAGE
THERMOSTAT
(NON-COMMUNICATING)
TWO-STAGE / MODULATING
GAS FURNACE CONTROL
CONDENSER
UNIT
1
2
R
C
HUM STAT
W1
W2
G
Y1
JUMPER
NOTE:1.) FOR TIMEDSTAGING, THE DIPSWITCHES 10 AND 11 (S2-10 AND S2-11)MUST NOTBE LEFT IN THE “OFF”POSITION. IF THESWITCHES LEFT IN THE ”OFF” POSITION WITH THISCONFIGURATION, THE FURNACE WILL NEVERGET TO HIGH STAGE HEAT. (SEEDIPSWITCH SECTIONOF THISBOOK).
2.) FORSING
LE STAGE COOLINGA JUMPERBETWEEN Y1 ANDY2 ISREQUIRED.
Y2
B
ARE
Page 54
54
Integrated Furnace Control
INTEGRATED FURNACE CONTROL
FIGURE 39
WIRING DIAGRAM FOR A LEGACY TWO-STAGE THERMOSTAT.
ST-A1194-62-04
THERMOSTAT WIRING DIAGRAMS-CONDENSING UNIT
(NON-COMMUNICATING)
TWO-STAGE
THERMOSTAT
(NON-COMMUNICATING)
TWO-STAGE / MODULATING
GAS FURNACE CONTROL
1
2
R
C
HUM STAT
W1
W2
G
Y1
Y2
CONDENSER
UNIT
B
Page 55
55
FIGURE 40
WIRING DIAGRAM FOR NON-COMMUNICATING HEAT PUMPS WITH COMMUNICATING FURNACE AND THERMOSTAT
ST-A1194-87-01
D. SPECIAL CONFIGURATION – WIRING OF NONCOMMUNICATING HEAT-PUMPS WITH
COMMUNICATING FURNACE AND THERMOSTAT (SEE
FIGURE 40).
Integrated Furnace Control
INTEGRATED FURNACE CONTROL
THERMOSTAT WIRING DIAGRAMS-CONDENSING UNIT (NONCOMMUNICATING)
A. WIRING DIAGRAM
COMMUNICATING THERMOSTAT AND FURNACE
COMMUNICATING THERMOSTAT
EcoNet
(CONTROL CENTER)
NON-COMMUNICATING
OUTDOOR UNIT
COMMUNICATING THERMOSTAT AND FURNACE
COMMUNICATING THERMOSTAT
EcoNet
(CONTROL CENTER)
NON-COMMUNICATING
OUTDOOR UNIT
ST-A1194-87-01
SPECIAL CONFIGURATION:
WITH NON-COMMUNICATING HEAT PUMP
(SINGLE - STAGE ONLY)
125 FEET MAX. @ 18 GA.
E1
E2
R
C
R
C
D
Y1
B
B. WIRING DIAGRAM
SPECIAL CONFIGURATION:
WITH NON-COMMUNICATING HEAT PUMP
(TWO - STAGE ONLY)
125 FEET MAX. @ 18 GA.
E1
E2
R
C
R
C
D
Y1
Y2
B
1
2
R
C
HUM STAT
W1
W2
G
Y1
Y2
B
SA2 OAT1
SA1
OAT2
1
2
R
C
HUM STAT
W1
W2
G
Y1
Y2
B
SA2 OAT1
SA1
OAT2
S1
S2
S3
O
HUM
HUM EAC
NEUTRAL
L1
S1
S2
S3
O
HUM
HUM EAC
NEUTRAL
L1
Page 56
56
FIGURE 41
WIRING DIAGRAM FOR A LEGACY SINGLE-STAGE THERMOSTAT WITH AUTOSTAGING.
ST-A1194-92-01
INTEGRATED FURNACE CONTROL
THERMOSTAT WIRING DIAGRAMS-CONDENSING UNIT
(NON-COMMUNICATING
Integrated Furnace Control
E. HEAT PUMP SYSTEMS W/LEGACY THERMOSTATS
E1. WIRING OF A SINGLE-STAGE LEGACY
THERMOSTAT WITH AUTOSTAGING SELECTED
(SEE FIGURE 41).
E2. WIRING OF A TWO-STAGE LEGACY THERMO-
STAT (SEE FIGURE 42)
SINGLE-STAGE
THERMOSTAT
(NON-COMMUNICATING)
TWO-STAGE / MODULATING
GAS FURNACE CONTROL
1
2
R
C
OUTDOOR
UNIT
HUM STAT
W1
W2
G
Y1
JUMPER
NOTE: 1.) FORTIMED STAGING, THE DIPSWITCHES 10AND 11 (S2-10 AND S2-11) MUST NOT BE LEFT IN THE “OFF”POSITION. IFTHE SWITCHES ARELEFT IN THE ”OFF”POSITION WITH THIS CONFIGURATION, THE FURNACE WILL NEVER GETTO HIGH STAGE HEAT. (SEE DIPSWITCH SECTION OFTHIS BOOK).
For connection to the low voltage side of the control
transformer. Terminals are ¼” quick-connect style.
20. FUSE (P100/P101)
A fuse is provided to protect low-voltage (24VAC)
circuits from shorts between 24VAC and Ground or
Common. A fault code 30 is displayed at the furnace
control when the fuse has been opened.
FIGURE 42
WIRING DIAGRAM FOR A LEGACY 2-STAGE THERMOSTAT
ST-A1194-93-01
TWO-STAGE / MODULATING
GAS FURNACE CONTROL
1
2
R
C
HUM STAT
W1
W2
D
G
Y1
Y2
B
Page 58
58
Field Selections
TIMING DIAGRAM, FIELD SELECTIONS &
ADJUSTMENTS
ADJUSTING OR CHECKING FURNACE INPUT
The maximum gas supply pressure to the furnace should
be 10.5" w.c. for natural gas and 13.0" w.c. for L.P. The
minimum gas supply pressure for purposes of input adjustment to the furnace should be 5" w.c for natural gas and
11.0" w.c. for L.P.
A calibrated manometer is required for accurate gas pres-
sure readings.
The manifold pressure should be set at 3.5" w.c. high fire,
1.8" low fire, for natural gas and 10.0" w.c. high fire and
4.9" w.c. low fire for L.P. Only small variations in the gas
flow should be made by means of the pressure regulator
adjustment. In no case should the final manifold pressure
vary more than plus or minus 0.3" w.c. from the abovespecified pressures. To adjust the pressure regulator, remove the regulator cap and turn the adjustment screw
clockwise to increase pressure or counterclockwise to decrease pressure. Then replace the regulator cap securely.
Any necessary major changes in the gas flow rate should
be made by changing the size of the burner orifices.
To change orifice spuds, shut off the manual gas valve and
remove the gas manifold. On LP gas furnaces, the LP gas
supply pressure must be set between 11" and 13" w.c. by
means of the tank or branch supply regulators. The furnace manifold pressure should be set at 10" w.c. at the gas
control valve. For elevations up to 2,000 feet, rating plate
input ratings apply. For high altitudes (elevations over
2,000 ft.), see conversion kit index for derating and orifice
spud sizes.
Checking furnace input is important to prevent over firing
beyond its design-rated input. NEVER SET INPUT ABOVE
THAT SHOWN ON THE RATING PLATE. Use the following table or formula to determine input rate. Start the furnace and measure the time required to burn one cubic foot
of gas. Prior to checking the furnace input, make certain
that all other gas appliances are shut off, with the exception of pilot burners. Time the meter with only the furnace
in operation.
TABLE 10
TIMING DIAGRAM
NOT MONITORED DURING LOW INDUCER SPD/LOW HT
Page 59
59
SETTING INPUT RATE
The furnace is shipped from the factory with #42 orifices.
They are sized for natural gas having a heating value of
1050 BTU/cu. ft. and a specific gravity of .60.
Since heating values vary geo-graphically, the manifold
pressure and/or gas orifice size may need to be changed
to adjust the furnace to its nameplate input. Consult the
local gas utility to obtain the yearly average heating value
and orifice size required to fire each individual burner at
25,000 BTU/HR.
NOTE: Refer to the High Altitude Section of this manual
and the National Fuel Gas Code for high altitude rate adjustment above 2,000 ft.
The importance of proper air flow over the heat exchanger cannot
be over emphasized.
One of the most common causes of heat exchanger failure is overheating due to low air flow. Airflow selections are in the dipswitch
section of this manual.
TEMPERATURE RISE CHECK
To determine if the air flow is correct, make a temperature rise
check.
1. Insert a thermometer in the supply air duct as close to the furnace as possible yet out of a direct line from the heat exchanger. See Figure 43.
2. Insert a thermometer in the return air duct as close to the furnace as possible.
3. Operate the furnace.
4. When the thermometer in the supply air duct stops rising (approximately five minutes), subtract the return air temperature
from the supply air temperature. The difference is the temperature rise.
5. Compare the measured temperature rise to the approved temperature rise range listed on the furnace name plate. See Figure 44.
If the measured temperature rise is above the approved range, either the air flow is too low or the manifold pressure needs to be adjusted. More air must be moved by speeding up the blower, by
removing restrictions in the duct system, or by adding more supply
or return air duct. If the measured temperature rise is below the approved range, either the air flow is too much or the manifold pressure needs to be adjusted. Use lower speed selection on the
variable speed blower.
IMPORTANT:
The measured temperature rise should be in the
middle of the range.
IMPORTANT: Some high-efficiency filters have a greater than normal resistance to airflow. This can adversely affect furnace operation. BE SURE TO CHECK AIRFLOW if using any filter other than
factory-provided filter.
!
CAUTION
IT IS IMPORTANT THAT EACH DUCT SYSTEM BE SIZED
AND INSTALLED FOR THE SPECIFIC APPLICATION BY
PROPERLY APPLYING THE APPROPRIATE INDUSTRY ACCEPTED STANDARD. IF LESS THAN MINIMUM STANDARDS ARE APPLIED, THE EQUIPMENT USER COULD
EXPECT TO EXPERIENCE HIGHER UTILITY BILLS, MAJOR
COMPONENT FAILURE, VARYING DEGREES OF AIR
NOISE OR OTHER UNSATISFACTORY ISSUES, OVER
WHICH THE MANUFACTURER HAS NO CONTROL.
FIGURE 43
TEMPERATURE RISE MEASUREMENT
RHEEM SALESCOMPANY, INC.
FORT SMITH, ARKANSAS
MODEL NUMBERSERIAL NUMBER
MFG. DATE:CONTROL SYSTEM: XX
HOURLY INPUT RATING
MAXIMUM
Btu/hr (Kw)
HOURLY INPUT RATING
MINIMUM
Btu/hr (Kw)
FACTORY EQUIPPED FOR
FORGAS
IN THE U.S., AT ELEVATIONS ABOVE 2,000 FT. (610M), DERATE THE INPUT 4% PER 1,000 FT. (305M) ABOVE
SEA LEVEL THIS APPLIANCE EQUIPPED FOR ALTITUDES
ORIFICE
LIMIT SETTING
AUXILIARY LIMIT SETTING
MAXIMUM PERMISSIBLE GASSUPPLY PRESSURE TO FURNA
CE
MINIMUM GAS SUPPLY PRESSURE FORPURPOSESOF INPUT ADJUSTMENT
MANIFOLD PRESSURE
AIR TEMPERATURE RISE/
HIGH FIRE
LOW FIRE
MAXIMUM EXTERNAL STATI CPRESSURE
INCHES W.C. (kPa)
NATURAL GAS
IN. W.C.(kPa)
10.5 (2.61)
5.0 (1.24)
3.5 (0.87)
LPGASORPROP
IN. W.C.(kPa)
13.0 (3.23)
11.0 (2.73)
10.0 (2.49)
ASSEMBLED IN MEXICO
91-22176-11
CATE GORY I FORCED AIR FURNACE FOR INDOOR ONLY, IN A BUILDING
CONSTRUCTED ON-SITE.
ELECTRIC115 V. 60 HZ. 1PH., MINIMUM CIRCUIT AMPACITY ,IB MOTOR FLA ,ID MOTOR FLA
MAXIMUM OVERCURRENT PROTECTION DEVICE AMPERS.
Nox EMISSIO
N LIMIT(NANOGRAMS / JOULE)
°F(°C)
°F(°C)
°F(°C)
°F(°C)
TO
TO
# DMS
ENERGY
PERFORMANCE
VERIFIED
ST-A1194-100-00
802VA075417ZSA
XXXXXX
FIGURE 44
TYPICAL FURNACE NAME PLATE
!
WARNING
THE MEASURED TEMPERATURE RISE SHOULD BE AS
CLOSE TO THE MIDDLE OF THE STATED RANGE AS POSSIBLE. FOR EXAMPLE, IF THE RISE RANGE IS 40 TO 70°F
(4.5°-21°C), THE MIDDLE OF THE RISE RANGE IS 55°F
(12.8°C). IN ALL APPLICATIONS, THE INSTALLER MUST ADJUST THE TEMPERATURE RISE TO THIS “MIDDLE” POINT
AS CLOSELY AS POSSIBLE. ALSO, THE TEMPERATURE
RISE SHOULD NEVER BE ABOVE OR FALL BELOW THE
STATED RANGE. DOING SO COULD CAUSE DAMAGE TO
THE HEAT EXCHANGER OR INTERMITTENT OPERATION.
THIS COULD CAUSE INJURY OR DEATH AND WILL VOID
THE MANUFACTURER’S WARRANTY FOR THIS PRODUCT.
Page 61
61
Safety Features
SAFETY FEATURES
LIMIT CONTROL/HALC
The high limit cut-off temperature is set at the factory and cannot
be adjusted. The temperature setting prevents the air temperature leaving the furnace from exceeding the maximum outlet air
temperature, which, if exceeded, will shut the furnace down.
There are several reasons for a limit switch to open and almost
always involve low airflow through the furnace.
1. A dirty or restricted air filter.
2. A dirty or restricted cooling coil.
3. Undersized or restricted return air system.
4. Undersized or restricted supply air system.
5. A problem affecting the main blower:
A. A wrong speed selection.
B. Failing motor bearings.
C. Low voltage to the motor.
D. Dirty blower wheel.
E. Wrong motor rotation.
F. Blower wheel slipping on the
F. motor shaft.
G. Bad power factor correction choke.
6. Overfiring the furnace with too much gas pressure.
7. Ventilation problems.
8. Failed blower motor.
FLAME ROLL-OUT SAFETY SWITCHES
Furnaces are equipped with safety switches to protect against
flame roll-out conditions in the burner compartment, which, if
tripped, will terminate the heating cycle. In the event of a flame
roll-out condition, the switch will shut the furnace down. Switches
for the furnaces are located on either side of the burner cover
plate and just above the burners on the blower divider panel. If a
switch is tripped, it must be manually reset. DO NOT jumper or
reset this switch. If this switch should trip, a qualified installer,
service agency or the gas supplier should be called to diagnose
and/or correct the source of tripping. If this unit is mounted in a
closet, the door must be closed when making this check.
PRESSURE SWITCH
This furnace is equipped with a normally-open pressure switches
that monitors pressure conditions within the furnace vent system
during the heating cycle.
There are several reasons for the pressure switch not to close.
1. An inoperative induced draft blower.
2. A loose or leaky pressure switch hose.
3. A blockage in the vent.
4. Severe downdrafts canceling the draft from the inducer fan.
5. A leaky gasket at the induced draft blower.
6. Improperly sized or installed vent.
The pressure switch contacts must open before the unit can go
through another heating cycle.
See diagnostic chart in this book for diagnostic recommendations.
!
WARNING
DO NOT BYPASS, JUMPER, OR REMOVE ANY SAFETY
SWITCH FROM THE FURNACE CONTROL CIRCUIT. IF A
SAFETY SWITCH CAUSES THE FURNACE TO SHUT
DOWN OR OPERATE INTERMITTENTLY, IT IS AN INDICATION OF A POTENTIAL SAFETY HAZARD THAT MUST BE
ADDRESSED BY A QUALIFIED TECHNICIAN, SERVICE
AGENCY OR THE GAS SUPPLIER. DO NOT RESET
SAFETY CONTROLS WITHOUT CORRECTIVE ACTION
AND/OR VERIFICATION OF PROPER SAFE OPERATION
BY A QUALIFIED INSTALLER, SERVICE AGENCY OR THE
GAS SUPPLIER.
REPLACE ANY SAFETY CONTROL COMPONENT ONLY
WITH IDENTICAL OEM REPLACEMENT PARTS. WHEN A
NEW SAFETY SWITCH IS INSTALLED, IT MUST BE
TESTED FOR A MINIMUM OF 15 MINUTES WITH THE
FURNACE OPERATING AT MAXIMUM INPUT RATE AND
WITH BOTH BLOWER AND BURNER DOOR INSTALLED.
IF THE FURNACE IS INSTALLED IN A CLOSET, THE
CLOSET DOOR MUST ALSO BE CLOSED FOR THIS
TEST. REPEAT THE TEST AT THE MINIMUM INPUT RATE
IF THE FURNACE IS A MULTI-STAGE FURNACE.
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62
Maintenance
MAINTENANCE
MAINTENANCE
FILTERS
LUBRICATION
IMPORTANT: DO NOT attempt to lubricate the bearings on
the blower motor or the induced draft blower motor. Addition of lubricants can reduce the motor life and void the
warranty.
The blower motor and induced draft blower motor are permanently lubricated by the manufacturer and do not require further attention.
It is recommended that the blower motor and induced draft
blower motor be cleaned periodically by a qualified installer, service agency, or the gas supplier to prevent the
possibility of overheating due to an accumulation of dust
and dirt on the windings or on the motor exterior. And, as
suggested elsewhere in these instructions, the air filters
should be kept clean. Dirty filters can restrict airflow. The
motor depends upon sufficient air flowing across and
through it to keep from overheating.
!
CAUTION
DO NOT OPERATE THE SYSTEM WITHOUT FILTERS.
A PORTION OF THE DUST ENTRAINED IN THE AIR
MAY TEMPORARILY LODGE IN THE AIR DUCT RUNS
AND AT THE SUPPLY REGISTERS. ANY RECIRCULATED DUST PARTICLES WILL BE HEATED AND
CHARRED BY CONTACT WITH THE FURNACE HEAT
EXCHANGER. THIS RESIDUE WILL SOIL CEILINGS,
WALLS, DRAPES, CARPETS AND OTHER HOUSEHOLD ARTICLES.
!
WARNING
THESE INSTRUCTIONS ARE INTENDED AS AN AID TO
QUALIFIED SERVICE PERSONNEL FOR PROPER INSTALLATION, ADJUSTMENT AND OPERATION OF THIS
UNIT. READ THESE INSTRUCTIONS THOROUGHLY BEFORE ATTEMPTING INSTALLATION OR OPERATION.
FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN IMPROPER INSTALLATION, ADJUSTMENT,
SERVICE OR MAINTENANCE, POSSIBLY RESULTING IN
FIRE, ELECTRICAL SHOCK, CARBON MONOXIDE POISONING, EXPLOSION, PROPERTY DAMAGE, PERSONAL
INJURY OR DEATH.
DISCONNECT MAIN ELECTRICAL POWER TO THE
UNIT BEFORE ATTEMPTING ANY MAINTENANCE.
FAILURE TO DO SO CAN CAUSE ELECTRICAL
SHOCK RESULTING IN PERSONAL INJURY OR
DEATH.
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63
ANNUAL INSPECTION
MAINTENANCE
• The furnace should operate for many years without excessive scale build-up in the flue passageways. However,
it is recommended that a qualified installer, service
agency, or the gas supplier annually inspect the flue passageways, the vent system and the main burners for continued safe operation. Pay particular attention to
deterioration from corrosion or other sources.
• IMPORTANT: It is recommended that at the beginning
and at approximately half way through the heating season, a visual inspection be made of the main burner
flames for the desired flame appearance by a qualified installer, service agency or the gas supplier. If the flames
are distorted and/or there is evidence of back pressure,
check the combustion and ventilation air system for blockage. If there is carbon and scale in the heat exchanger
tubes, the heat exchanger assembly should be replaced.
• IMPORTANT: It is recommended that at the beginning of
the heating season, the flame sensor be cleaned with
fine steel wool or Scotch Bright Pad by a qualified installer, service agency or the gas supplier.
• IMPORTANT: It is recommended that an annual inspection and cleaning of all furnace markings be made to assure legibility. Attach a replacement marking, which can
be obtained through the distributor, if any are found to be
illegible or missing.
REPLACEMENT PARTS
Please visit www.myrheem.com/myruud.com for replacement parts information.
WIRING DIAGRAM
Figure 48 is a complete wiring diagram for the furnace.
A wiring diagram is also available on the unit.
SYSTEM OPERATION INFORMATION
ADVISE THE CUSTOMER
1. Keep the air filters clean. The heating system will operate better, more efficiently and more economically.
2. Arrange the furniture and drapes so that the supply air
registers and the return air grilles are unobstructed.
3. Close doors and windows. This will reduce the heating
load on the system.
4. Avoid excessive use of kitchen exhaust fans.
5. Do not permit the heat generated by television, lamps
or other heat generating devices to influence the thermostat operation.
6. Except for the mounting platform, keep all combustible
articles 3 feet from the furnace and vent system.
7. IMPORTANT: Replace all blower doors and compart-
ment covers after servicing the furnace. Do not operate the unit without all panels and doors securely in
place.
8. Explain the advantages of continuous fan operation to
the customer.
!
WARNING
HOLES IN THE VENT PIPE OR HEAT EXCHANGER
CAN CAUSE TOXIC FUMES TO ENTER THE HOME,
RESULTING IN CARBON MONOXIDE POISONING
OR DEATH. THE VENT PIPE OR HEAT EXCHANGER
MUST BE REPLACED IF THEY LEAK.
Maintenance
Page 64
64
Diagnostics
TABLE 12
802V NORMAL OPERATION CODES
DIAGNOSTICS
Below are two lists; a list of normal operating codes and a
list of fault codes. The fault code list provides diagnostic
and troubleshooting information to help determine the
problem and fix it. Normal operating codes are not fault
codes and the presence of a normal operating code indicates a no-fault condition.
NOTE: Verify display orientation is correct before interpreting fault codes. Otherwise, the fault codes may be upsidedown. If a fault code or operating code is not on these
lists, the display may be upside-down.
-
NORMALOPERATION CODES
Key
CODE
DISPLAYED
AT DUAL
SEVEN-
SEGMENT
DISPLAY OF
CONTROL
NORMALOPERATION CODE
0
H or h
DESCRIPTION: This code is displayed anytime there is no fault present and no thermostat call present. The furnace is idle.
DESCRIPTION: This code is displayed anytime there is a call for gas heat. The lower-case "h" is displayed when the
thermostat is requesting low gas heat and the upper-case "H" is displayed when the thermostat is requesting high-stage gas
heat.
NAME
DESCRIPTION
STANDBY MODE
GAS HEAT MODE
C or c
HP or hP
Cd or cd
F
dF
COOLING MODE
DESCRIPTION: This code is displayed anytime there is a call for cooling. The lower-case "c" is displayed when the thermostat
is requesting low-stage cooling and the upper-case "C" is displayed when the thermostat is requesting high-stage cooling.
HEAT-PUMP HEATING MODE
DESCRIPTION: This code is displayed anytime there is a call for heat-pump heat. The lower-case "hP" is displayed when the
thermostat is requesting low-stage heat-pump heat and the upper-case "HP" is displayed when the thermostat is requesting high
stage heat-pump heat.
CONTINUOUS FAN MODE
DESCRIPTION: This code is displayed anytime there is a call for continuous fan from the thermostat.
DEFROST MODE
DESCRIPTION: This code indicates that the heat-pump is in defrost mode (dual-fuel systems only) and furance is operating for
defrost operation which is fixed at low-stage gas heating operation.
COOLING IN DE-HUMIDIFICATION MODE
DESCRIPTION: This code indicates that there is a both cooling and dehumidication demand present at the same time. When
de-humidification is active, the cooling airflow will be reduced in order to allow water to accumulate on the condenser therby
removing humidity from the conditioned environment. The lower-case "cd" is displayed when the thermostat is requesting lowcooling with de-humidification and the upper-case "Cd" is displayed when the thermostat is requesting high-stage cooling with
de-humidification.
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65
TABLE 13
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
Diagnostics
Key
FAULT CODE
DISPLAYED
AT DUAL
SEVEN-
SEGMENT
DISPLAY OF
CONTROL
FAULT CODES
STATUS: This isacritical fault. The furnace will not operate in any mode.
DESCRIPTION: Thiscode is displayed anytime there is no model data at the furnace or (forcommunicating systems only) on
the network (e.g. at the condenser or thermostat). The model data is electronically stored data that is used to defi
other things) blower operation. Without the model data, the furnace can not function. Note that model data may be available
even if there is no card attached to the furnace control. A missing memory card will display fau
available on the network.
EXPECTED OPERATION: No operation (including thermostat) will be permitted without the model data. The model data
defines the IBM (Indoor Blower Motor) speed-torque curve. Without this information, the IBM can not operate. Refer to the
d1
section of thi
the hierarchy of use of multiple copies of model data and distribution (among other details) of model data.
CAUSE: Typically, the memory card will be missing from the furnace. Inmostcases, the causeofthis fault will bethe lossor
disconnection of the original memory card from the furnace control (or I.F.C.). When the furnace
the memory card must be saved and installed in the replacement control.
SOLUTION: Replace the missing memory card into the connector labeled P6 on the furnace control (I.F.C.). If the original card
can not be found, a replacement card can be ordered from ProStock. Be sure to order the correct memory card for
Note: Furnace power must be cycled off and then on again after replacing the card or the model data will not be read.
s manual titled "INTEGRATED FURNACE CONTROL" under the subsection titled "MEMORY CARD" for details on
FAULT CODES
DISPLAYED TEXT
STATUS
DESCRIPTION
EXPECTED OPERATION
CAUSE
SOLUTION
NO MODEL DATA
ne(among
ltcode"d4" ifmodel data is
control (or I.F.C.) isreplaced,
thefurnace.
STATUS: This isanon-critical fault. Thefurnaceshould operate in any mode.
DESCRIPTION: The memory card inserted into the slot at position P6 of the furnace control is corrupt and can not be used OR
there is no memory card installed at all. However, a valid copy of model data for the furnace still resides in the
microprocessor.
EXPECTED
Operation should proceed as normal with this fault (d4) only being displayed during the standby mode.
d4
CAUSE
card has corrupted and can not be properly read.
SOLUTION
memorycard. Neverreplace the memory cardof a furnace with a memory card from another furnace orcomponent (e.g.
condenser or air handler). Doing so could result in improper operation of the blower which may cause damage to the
heat exchanger. If the original memory card for the furnace control is available and working, it must be used. A correct
replacement memory card can be ordered from ProStock. Be sure to have the furnace model and serial number available when
ordering.
OPERATION: model datafromthememorycardcannotbeusedbecause it is invalid or not present at all.
This isanon-critical fault. Thefurnaceshouldoperate inanymode.
STATUS:
DESCRIPTION: Thehorsepower reported by themotor does not matchthe horsepower stored inmemory inthe model data of
the memory card. However, the model data stored on the microprocessor of the furance control does match the attached motor.
NO VAL ID MODEL DATA ON MEMORY CARD
EXPECTED OPERATION:
as normal with this fault (d6) only being displayed during the standby mode.
: There are two possible causes for this fault: (1) The blower motor has recently been replaced and the wrong
CAUSE
d6
horspower motor was used. (2) The memory card or furnace control has recently been replaced and the wrong card or
replacement
SOLUTION:
anew,correctpart. Neverreplace the memory cardof a furnace with a memory card from another furnace or
component (e.g. condenser or air handler). Doing so could result in improper operation of the blower which may cause
damage to the heat exchanger. If the original memory card for the furnace control is available and working, it must be
used. A correct replacement memory card can be ordered from ProStock. Be sure to have the furnace model and serial
number available when ordering.
control wasused.
Determine the correct motor and/or model datacardforthefurnaceandreplacethe incorrectordamagedpartwith
model data from the memory card can not beusedbecause it is invalid. Operationshouldproceed
furnace
Page 66
66
Diagnostics
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
STATUS
: This isacritical fault. Thefurnacewill notoperate ingasheatmodesbutall othermodes(e.g. cooling)should
function.
DESCRIPTION
1. Whenafailed ignitionhasoccurred four times in a row, thecontrol enters one-hour lockout and fault codes “10” and “11” will
be displayed alternately at the seven-segment display. See fault code 11 for a description on expected operation, causes and
solutions for this fault code.
While the control has entered a one-hour lockout after
2.
more than 150 seconds, the fault codes “61” (Non-operational blower) and “10” (soft lockout) will be displayed alternately at the
seven-segment display. Note: the dead blower fault and associated one-hour lockout will occur up to four times in one heat call.
Upon declaring this fault for the fourth time in one heat call, the control w
the furnace. See fault code 61 for a description on expected operation, causes and solutions for this fault code.
10
When IFC is insoft lockoutandfaul
3.
the furnace seven-segment display. See fault code 93 for a description on expected operation,
fault code.
4.
When flame is lost five times in a row, the control enters
alternately at the IFC seven-segment display. See fault code 13 for a description on expected operation, causes and solutions
for thi
While the control is in one-hour lockoutduetoanunexpectedflame,thefaultcodes“14”(unexpectedflame)and“
5.
lockout) will be displayed alternate
operation, causes and solutions for this fault code.
STATUS: Up to three failed ignitions will not constitute acritical condition. Critical condition (with no heating operation) is only
noted when the furnace has failed to ignite four or more times
one-hour lockout and the dual faults "11" and "10" are alternately displayed at the IFC's seven-segment display.
DESCRIPTION
until successful ignition or the furnace control has failed to ignite four consecutive times
fault is elevated to "10" and the furnace control (or I.F.C.) reacts as described under description for the fault code "10".
Note: This fault will not be displayed to the homeowner
single heat call. It will not be displayed to the homeowner after the first or even second failure. However, it will be displayed in
active fault screen of thermostat immediately after the first failure (and all subsequent failures) during a single heat call.
the
Further, this fault (11) will only be logged into the fault buffer one time. It will
consecutively. After four failed ignition attempts,the IFC enters
. After four attempts, the status of the
on communicating systems unless it occurs at least three times within a
not log more than once in the buffer.
10” (soft
EXPECTED OPERATION
second post-purge followed by a second ignition attempt. This cycle will be repeated until gas heat is
11
fourth failed ignition attempt. After the fourth failed attempt, the furnace control (IFC) will proceed to one-hour lockout.
CAUSE
: Therecanbeseveral causesforafailed ignitionattempt(s). The most common are:
(1) The flame sense rod is unable to sense flame
(2) The gas valve may be turned off.
(3) The igniter is not working properly. It may not be properly connected or the spark location may not be correct.
(4) The furnace control may not be working properly and may need to be replaced.
(5) The flame may not be properly spreading from the first burner to the last.
SOLUTION
(1)
Make sure furnace ground is properly connected.
(2) Turn the valve on.
(3) Replace or reposition the igniter or check all connections and wire
(4) Replace the furnace control.
(5) Check the manifold pressure during ignition. For natural gas it should be approx. 3.5" wc and for LP gas it should be approx.
10" wc. If manifold pressure is good, watch the burner during ignition. If the
do not light, the burner may need to be replaced.
: The solutionwill depend onthecause. Solutionstonotedcauses(1)through(5)aboveare:
Clean or replace the flame sense rod or check all connections and wire between the rod and the furnace control (or I.F.C.).
: After the first failed ignition attempt, the fault ("11") is displayed and the inducer will complete a 20
establishedoruntil the
. It may need cleaning or may not be properly connected.
between the igniter and the furnace control (or I.F.C.).
firstburner lights,butthesecond,thirdandsoon
Page 67
67
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
Diagnostics
STATUS: The statusofthisfault isnon-critical andfurnaceoperationwill continueasnormal inheating(andall other)mode(s).
If flame sense is low, the furnace control (or I.F.C.) may soon no longer be able to
problem may be elevated to the level of fault code "13" or fault "11" (if flame can not be sensed at all).
DESCRIPTION: The flamesensecurrentfromtheflamesenserodatthefurnacecontrol (or I.F.C.) isweak ormarginal atbest.
EXPECTEDOPERATION
the furnace control (I.F.C.) and "LO FLAME SENSE" displayed in the fault area of a communicating
12
:
CAUSE
(1) The most common cause for low flame sense during heat operation is that the flame sense rod may need
not be properly connected or wiring between the rod and the furnace control may be shorted or opened.
(2) Another cause for low flame may be an improperly mounted or poorly grounded flame sensor.
SOLUTION
(1) Clean or replace the flame sense rod or check all connections and wire between the rod
(2) Reinstall or replace flame sensor and check wiring and connections. Also make sure the furnace is properly grounded.
:
: All operation (including gas heat) will proceed as normal with only the fault code ("12") displayed at
LOW FLAME SENSE
properly sense the flame and status of the
thermostat.
cleaningormay
andthefurnacecontrol (or I.F.C.).
STATUS: Flame loss isnotacritical fault. Subsequent ignitionattemptswill followandnormal operationshouldresume.
However, a lost flame can often be followed by failed ignition attempts then a one-hour lockout.
one-hour lockout, the fault condition is critical (although attempts at ignition will be made again after the 1 hour lockout).
DESCRIPTION
any time after successful ignition while a valid heat call is present.
EXPECTEDOPERATION: When flame is lost, the fault code ("13") is immediately displayed at the IFC SSD's. The IBM (Indoor
Blower Motor) is energized (if it was not already) at the correct speed (based on the demand from the thermostat)
completes a 90 second blower off delay. The IDM (Induced Draft Motor) remains energized at the most recent speed (based on
the demand from the thermostat or as required for ignition cycle) for a 20 second post-purge. After
blower off delay are complete, the fault code ("13") is removed and a new attempt at ignition is made. Often, the new ignition
attempt will fail and operation will proceed as though a failed ign
Note: This fault will not be displayed to the homeowner on communicating systems unless it occurs at least three times within a
single heat
the active fault screen of thermostat immediately after the first failure (and all subsequent failures) dur
13
Further,thisfault (13) will onlybe logged intothefaultbufferonetime. Itwill not logmorethanonce inthebuffer.
CAUSE
(1) The most common cause for low flame sense during heat operation is that the flame sense rod may need cleaning or may
not be properly connected or wiring between the rod and the furnace
(2) Another cause for low flame may be an improperly mounted
(3) Flame pattern may be unstable.
SOLUTION
(1) Clean or replace the flame sense rod or check all connections and wire between the rod and the furnace control (or I.F.C.).
(2) Reinstall or replace flame sensor and check wiring and connections. Also mak
(3) Check that all burner assembly components are properly installed. Check for good seals between the burner and blower
compartments. Insure that the combustion door gasket is in place and the door is properly
: After a successful ignition trial, the flame (which was properly sensed) is no longer sensed. This can happen
itionhasoccurredfromthatpoint(seefaultcode "11").
call. Itwill notbedisplayedtothehomeownerafterthefirstorevensecondfailure. However, itwill bedisplayed in
:
control maybeshortedoropened.
orpoorlygroundedflamesensor.
:
e sure the furnace is properly grounded.
Once the status has reached
both the post-purge and
ingasingleheatcall.
installedandsealed.
FLAME PRESENT WITH GAS VALV E OFF
: This isanextremelycritical faultandshouldrarely (ifever)beseen inthefield. Thefurnacewill notoperatewiththis
STATUS
FLAME LOST AFTER ESTABLISHED
fault present.
DESCRIPTION
supposed to be off.
EXPECTEDOPERATION
speed and IDM (Induced Draft Motor) is energized at high speed. Both will remain energized until the fault is cleared.
Response to any
energized when the unexpected flame was sensed. When the condition causing the fault is cleared, the I
second post-purge and the IBM will complete a 90 second blower off-delay. The control will then enter a one-hour lockout and
14
display the fault codes "10" (one-hour lockout) and "14" (unexpected
Operation is returned to normal after the lockout period.
CAUSE
(1) Field mis-wiring of 24VAC to the gas valve ma
(2) Faulty gas valve stuck in the "OPEN" position.
(3) Faulty furnace control (signal improperly sensed when it should not be sensed at all).
SOLUTION
(1) Wire properly.
(2) Replace gas valve.
(3) Replace furnace control.
: Thisfault indicatesflame ispresentwhen itshouldnotbe. Flame isseentobepresentwhenthegasvalve is
: Whenunexpectedflame issensed,the IBM (Indoor Blower Motor) is energized at maximum heat
thermostat call is not permitted until the fault is cleared. Note that the gas valve circuit should not have been
DM will complete a 20
flame) alternately for the duration of the one-hour lockout.
:
insolenoid.
:
and
Page 68
68
Diagnostics
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
Page 69
69
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
Diagnostics
STATUS: This isacritical fault. The furnace will not operate in any mode.
DESCRIPTION: The fusehasbeenopened. Thisusuallyoccurswhenthere isa24VACshorttocommonorgroundon the low-
votage side of the transformer.
30
EXPECTED OPERATION
CAUSE
:
An electrical short from low voltage (24VAC) to ground or common has occurred.
SOLUTION
Repair the short circuit condition and replace fuse.
:
: The fault code is displayed and no other operation can take place.
OVER-TEMPERATURE SWITCH (ROLL-OUT)OPEN (AKAMRLC)
STATUS: This isacritical fault. Thefurnacewill notoperate ingasheatmodesbutall othermodes(e.g. cooling)should
function.
DESCRIPTION
on any given furnace. When one or more of these limits open, they must be manually pushed bac
(hence the name; Manually Reset) to force the acknowledgement of a critical fault. This fault will occur when flames have rolled
out of the normal area in the heat exchanger and into the burner
field and indicates a very serious problem that must be repaired before furnace operation can continue.
: The ManuallyResetLimitControl (M.R.L.C.) isalso knownbythename"RolloutLimit". Therecanbeseveral
OPEN FUSE
k to the closed position
compartment. This fault should rarely (if ever) be seen in the
EXPECTED OPERATION
Motor) is energized at maximum heating speed. The gas valve circuit is de-energized (if it was energized)
Draft Motor) is energized at high speed. Response to thermostat cooling calls will take place as normal with IBM energizing at
the higher of the two blower speeds (high heat or cool) when
IDM will remain energized for a 20 second post-purge and the IBM will remain energized for the user-selected blower off-delay
33
period.
:
CAUSE
(1) Insufficient venting through either the inlet or exhaust.
(2) Loose or faulty wiring.
(3) Unstable flame pattern.
SOLUTION
(1) Check that the pressure switch(es) have not been we
proper rpm. Insure that the venting does not exceed the maximum specified lengths. Check for obstructions in combustion
venting. Check that all gaskets between the inducer and center
(2) Check wiring and connections. Replace and/or repair as necessary.
(3) Check that all burner assembly components are properly installed. Check that all seals between the burner and blower
compartments are tight. Insure that the door seals are in place and that the burner door is properly installed and does not
Check to make sure that the heat exchanger has not been damaged; i.e.: crushed tubes, breached collector box and etc.
:
: WhentheMRLC(ManuallyResetLimitControl) circuithasbeenopened,the IBM (Indoor Blower
STATUS: This isacritical fault. Thefurnacewill notoperate ingasheatmodesbutall othermodes(e.g. cooling)should
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode)
DESCRIPTION
of a serious condition. The switch may be welded closed or purposely bypassed in
the pressure switch is tested to make sure that it is opened. The switch is ignored except in gas heating modes.
homeowner and technician. The fault code is only present during a heat call before pre-purge begins.
44
CAUSE
(1) Faulty switch.
(2) Pressure switch physically bypassed in the field.
(3) Loose or faulty wiring.
(4) Abnormally high negative pressure present on vent system without inducer running.
SOLUTION
(1) Replace low pressure control (switch).
(2) Remove bypass and restore correct operation. Determine reason for bypass (e.g. vent length too long) and correct issue.
Not
ify homeowner and proper authorities of illeagle tampering if necessary.
(3) Check wiring and connections. Replace and/or repai
(4) Check for proper venting and terminations as defined in the furnace installation instructions.
: The low pressure control (or switch) should not be closed when the inducer is not running. If it is, this is a sign
:
:
rasnecessary.
.
thefield. Beforeanyheatcyclecanbegin,
andthe IDM (Induced
leak.
Page 70
70
Diagnostics
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
STATUS: This is a critical fault. The furnace will not operate ingasheatmodes but all other modes (e.g. cooling) should
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode)
DESCRIPTION
switch must close after the inducer is energized and before the ignition sequence can begin. The switch is ignored except in
heating modes.
EXPECTEDOPERATION: (1) DISPLAYED BEFORE HEAT IS ESTABLISHED:The IBM (IndoorBlowerMotor)will notbe
energized. The fault code will not be displayed until the IDM (Induced Draft Motor) has been energized for a minimum of ten
seconds. The IDM will remain energized at the
after the beginning of the pre-purge attempt. After five minutes, the IDM is de-energized and second attempt at pre-purge is
made (as
heat call is lost. (2) DISPLAYED
valve will be de-energized, the IBM will be energized (if not already energized) at the correct heat speed (determined by the
firing rate requi
blower off-delay and the IDM will complete a 20 second post-purge (at high speed). After these delays, a new attempt
will be made provided the call for heat is still present.
45
CAUSE
(1) Blockage or improper termination in either the inlet or exhaust vents.
(2) The flue vent length and/or number of elbows exceeds the maximum number specified.
(3) Faulty or disconnected inducer.
(4) Fau
(5) Loose or faulty wiring.
(6) Disconnected, blocked, split or cut pressure switch hoses.
(7) Wind gusts (sporadic).
(8) Faulty pressure switch.
SOLUTION
(1) Check the vent system for blockage and proper termination and repair as necessary.
(2) Check the specification sheets and/or installation instructions. Remove excess venting.
(3) Repair or replace inducer and/or inducer wiring and/or electrical connections.
(4) Replace control board.
(5) Check wiring and connections. Replace and/or repair as necessary.
(6) Replace hoses as necessary.
(7) Insure proper termination and determine if high altitude kit may be necessary (see item 4)
(8) Replace the pressure switch.
STATUS
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode)
DESCRIPTION
the furnace only ignites at high fire, this condition should never be seen except after the blower on delay period of the
cycle and only after the furnace attempt to switch to low stage heating. The switch is ignored except in heating modes.
EXPECTEDOPERATION: This fault is displayed only after heat is established and switched to low fire with the IBM (Indoor
Blower Motor) energized at low speed. When this fault is displayed the gas valve w
energized at the low heat speed and the IDM (Induced Draft Motor) will remain energized at the low speed. The IBM will
complete the user-selected blower off-delay (at low speed) and
After these delays, a new attempt at ignition will be made provided the call for heat is still present.
CAUSE
(1) Blockage or improper termination in either the inlet or exhaust vents.
(2) The flue vent length and/or number of elbows exceeds the maximum number specified.
(3) Faul
46
(4) Faulty control board (inducer relay).
(5) High altitude kit not installed in areas of high elevation.
(6) Loose or faulty wiring.
(7) Disconnected, blocked, split or cut pressure switch hoses.
(8) Wind gusts (sporadic).
(9) Faulty pressure switch.
SOLUTION
(1) Check the vent system for blockage and proper termination and repa
(2) Check the specification sheets and/or installation instructions. Remove excess venting.
(3) Repair or replace inducer and/or inducer wiring and/or electrical connect
(4) Replace control board.
(5) Check elevation of the installation and consult the specifications for the furnace to determine if a high altitude kit is needed.
Install proper kit as necessary.
(6) Check wiring and connections. Replace and/or repair as necessary.
(7) Replace hoses as necessary.
(8) Insure proper termination and determine if high altitude kit may be necessary (see i
(9) Replace the pressure switch.
: Thisfault indicatesthatthe lowpressureswitch isopenwhen the inducer is energized at high speed. The
AFTER HEAT IS ESTABLISHED - Ifthisfault isdisplayedafterheat isestablished,thegas
at ignition
LOW PRESSURE SWITCH OPEN, INDUCER ON LOW SPEED
.
ignition
ill bede-energized,the IBMwill remain
the IDMwill completea20secondpost-purge(at lowspeed).
irasnecessary.
ions.
tem4)
Page 71
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TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
Diagnostics
STATUS: This is a critical fault. The furnace will not operate ingasheatmodes but all other modes (e.g. cooling) should
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode)
DESCRIPTION
of a serious condition. The switch may be welded closed or purposely bypassed
the pressure switch is tested to make sure that it is opened. The switch is ignored except in gas heating modes.
EXPECTEDOPERATION
homeowner and technician. The fault code is only present during a heat call before pre-purge begins.
55
CAUSE
(1) Faulty switch.
(2) Pressure sw
(3) Loose or faulty wiri
(4) Abnormally high negative pressure present on vent system without inducer running.
SOLUTION
(1) Replace high pressure control (switch).
(2) Remove bypass and restore correct operation. Determine reason for bypass (e.g. vent length too long) and correct issue.
Notify homeowner and proper authorities of illeagle tampering if necessary.
(3) Check wiring and connections. Replace and/or repair as necessary.
(4) Check for proper venting and terminations as defined in the furnace installation instructions.
STATUS
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode)
heat operation and the low pressure switch remains engaged, the furnace will switch to low fire heat and continue to run (if
possible) to try to satisfy the
DESCRIPTION
fault can be displayed any time during the heat call except during low heat call and on
delays are complete.
EXPECTEDOPERATION
energized. The fault code will not be displayed until the IDM (Induced Draft Motor) has been energized for a minimum of ten
seconds. The IDM will remain energized at the
after the beginning of the pre-purge attempt. After five minutes, the IDM is de-energized and second attempt at pre-purge is
made (as
heat call is lost. (2) DISPLAYED AFTER HEAT IS ESTABLISHED
will remain energized at high speed and the firing rate will drop to low stage provided the low pressure switch remains closed.
The IBM will
provided until the heat call ends or the high pressure switch closes. If the high pressure switch
speed will be adjusted to the correct (higher) rate required by the thermostat and the IDM will remain energized at high speed. If
the low pressure switch also will not remain closed,
: The high pressure control (or switch) should not be closed when the inducer is not running. If it is, this is a sign
:
itchphysicallybypassed inthefield.
:
: This isacritical fault. Thefurnacewill notoperate ingasheatmodesbutall othermodes(e.g. cooling)should
: Thisfault indicatesthatthehighpressureswitch isopenwhenthe inducer is energized at high speed. This
long as the heat call is still present). This cycle is repeated indefinately until either the pressure switch closes or the
energize at, or switch to, the low-fire rate (also provided the low pressure switch remains closed). Low heat is
- If this fault is displayed after heat is established, the IDM
closes,theheatrateandblower
operation will be as described under fault code # 46 ("LPC OPEN") above.
57
58
:
CAUSE
(1) Blockage or improper termination in either the inlet or exhaust vents.
(2) The flue vent length and/or number of elbows exceeds the maximum number specified.
(3) Faulty or disconnected inducer.
(4) Faulty control board (inducer relay).
(5) High altitude kit not installed in areas of high elevation.
(6) Loose or
(7) Disconnected, blocked, split or cut pressure switch hoses.
(8) Wind gusts (sporadic).
(9) Faulty pressure switch.
SOLUTION
(1) Check the vent system for blockage and proper termination and repair as necessary.
(2) Check the specification sheets and/or installation instructions. Remove excess venting.
(3) Repair or replace inducer and/or inducer wiring and/or electrical connections.
(4) Replace control board.
(5) Check elevation of the insta
Install proper kit as necessary.
(6) Check wiring and connections. Replace and/or repair as necessary.
(7) Rep
(8) Insure proper termination and determine if high altitude kit may be necessary (see item 4)
(9) Replace the pressure switch.
STATUS
(e.g. cooling) should function if a call is present.
llationandconsultthespecificationsforthefurnacetodetermine if a high altitude kit is needed.
lacehosesasnecessary.
: This isacritical faultexperiencedbythefurnace. The furnace will not operate in gas heat modes but all other modes
: The IFC cannot detect electrical continuity between pins 1 and 2 of connector P4 of the furnace control. The
: Nogasheatingoperationcanproceedandthefault isdisplayed. All othermodes(e.g. cooling)of
Jumper wire or connector has been compromised.
:
WATER CIRCUIT OPEN
Page 72
72
Diagnostics
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
: This isanon-critical faultexperiencedbythefurnace. All operations (including thermostat calls) should continue as
STATUS
normal with no perceivable difference in operation.
DESCRIPTION
EXPECTED OPERATION
compromised but will continue.
60
CAUSE
(1) The blower has hit the maximum speed or
because the static pressure is too high.
SOLUTION
(1) The static pressure is too high because the ductwork is improperly designed or is restricted for some other reason or the
filter needs cleaning
values in the specification sheets or installation instructions.
: A blowerfaultwhich isnon-critical allowstheblowertocontinuetorunbutat less-than-optimal conditions.
: All (including thermostat) operation should continue as normal. Blower operation may be slightly
torque limit specified by the manufacturer or is running at the temperature limit
STATUS: This isacritical fault. The furnace will not operate in any mode.
BLOWER FAULT - MOTORCANNOT RUN
EXPECTED OPERATION
stop and the furnace will shut down normally with post-purge at the correct speed. After the post purge (or immediately if no
heat call was present), no other operation (including thermostat calls) will occur until this fault is cleared.
This fault may be displayed in heating or cooling modes and may also be displayed in
has been opened four times consecutively for more than 150 seconds (2m:30sec) each time. If this happens, the IFC
determines that the motor and/or blower is not functional and enters a hard
and manual reset of power to the furnace.
CAUSE
61
:
(1) The motor has tripped on thermal limit because of
(2) The motor Power Factor Correction (P.F.C.) choke is faulty and needs replacing.
(3) The furnace model data is faulty or corrupted.
(4) Wiring to the motor and/or P.F.C. has become
(5) The blower wheel has become damaged or is not properly attached to the motor shaft.
(6) The motor has failed catastrophically.
SOLUTION:
(1) Remove obstruction or replace motor.
(2) Replace the Power Factor Correction choke.
(3) Replace the furnace memory card with the correct replacement part from ProStock.
(4) Inspect and replace or repair wiring and/or connectors to the motor and/or P.F.C. as necessary.
(5) Replace the blower wheel and/or attach the blower wheel to the motor shaft properly.
(6) Replace the motor.
: If thefurnacewas inheatingoperationwhenthisfaultoccurred,bloweroperationwill immediately
heating mode after the main limit control
lockoutconditionrequiringrepairoftheblower/motor
arestrictionorbearingfailure.
compromised.
Page 73
73
TABLE 13 (continued)
802V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
r
Diagnostics
STATUS: This is a non-critical fault experienced by the furnace. All operations (including thermostat calls) should continue as
normal with no perceivable difference in operation.
DESCRIPTION
more torque or speed in order to get the desired airflow under the current static pressure condit
operate because internal software will prevent operation above the permitted range. However, a fault is sent to the furnace
control (or I.F.C.) from the motor. Note: This fault will
not be displayed after
fault buffer or fault history after the first hour of operation and will only be logged into the faul
This code (66) indication is intended as a tool to notify the installer of inadequate airflow due to excessive static pressure in the
duct of the system. The code is not intended to
66
: The blower motor is operating at the highest rpm or torque that specifications allow but the application requires
be a fault code. It is merely an operating indicator.
EXPECTEDOPERATION
compromised but will continue.
:
CAUSE
(1) The blower has hit the maximum speed or torque limit specified by the manufacturer because the static pressure is too high.
SOLUTION
(1) The static pressure is too high because the ductwork is improperly
filter needs cleaning or replacing. Remove the obstruction or repair the duct so that static pressure does not exceed published
values in the specification sheets or
:
: All (including thermostat) operation should continue as normal. Blower operation may be slightly
designedor isrestrictedforsomeotherreasonorthe
installation instructionsforthefurnace.
NO BLOWER COMMUNICATIONS
STATUS: This isacritical fault. The furnace will not operate in any mode.
DESCRIPTION: The furnace control (I.F.C.) cannotcommunicatewiththeblowermotor.EXPECTED OPERATION
(flame will be lost), IBM (Indoor Blower Motor) operation will immediately stop and the furnace will shut down norma
without IBM operation) with IDM (Induced Draft Motor) post-purge at the correct speed. After the post purge (or immediately if
no heat call was present), no other operation (including thermostat calls) will occur until this
:
CAUSE
68
(1) The wires between the blower motor have been disconnected or there is a poor connection.
(2) There is no line voltage to the motor.
(3) The furnace model data is faulty or corrupted.
(4) The motor has failed catastrophically.
SOLUTION
(1) Check wiring, connectors and terminals - repair or replace as necessary.
(2) Check line voltage wiring, connectors and terminals to the Power Factor Correction choke and ECM motor. Repair and
replace as necessary.
(3) Replace the furnace memory card with the correct replacement part from ProStock.
(4) Replace the motor.
:
: If the furnace was in heating operation when this fault occurred, the gas valve will immediately close
fault is cleared.
INTERNAL CONTROL FAULT DETECTED
STATUS: This isacritical fault. The furnace will not operate in any mode of operation.
DESCRIPTION: This is a severe fault that should rarely (if ever) be discovered in the field. It
microprocessor fault on the furnace control (or I.F.C.) or voltage applied to the main gas valve solenoid when there should be
none.
EXPECTEDOPE
immediately close (flame will be lost), IBM (Indoor Blower Motor) operation will immediately stop and
normally (except without IBM operation) with IDM (Induced Draft Motor) post-purge at the correct speed. After the post purge (o
immediately if no heat call was present), no other operation (including thermostat calls) will occur until this fault is cleared.
93
However, this fault may also indicate an internal microprocessor failure. This may
expected and that all outputs will be de-energized and gas valve closed immediately when the fault is sensed.
CAUSE:
(1) 24VAC or similar voltage applied to the main gas valve solenoid circuit unexpectedly.
(2) Furnace control software test failure - failed furnace control (or I.F.C.).
SOLUTION:
(1) Check for miswiring in the furnace.
(2) Replace the furnace control (or I.F.C.).
99
This is a notification that fault codes in the fault buffer have been reset.
RATION: If possible, ifthefurnacewas inheatingoperationwhenthisfaultoccurred,thegasvalvewill
mean that the heat call will not end as
REMOTE FAULTS RESET PERFORMED
is an indicatorofan internal
thefurnacewill shutdown
lly (except
Page 74
74
Diagnostics
DIAGNOSTICS
LOCKOUT AND REPLACING THE FURNACE CONTROL
All lockout conditions can be cleared immediately provided
that the original fault causing the lockout is cleared and
power to the unit is cycled off and then back on again or
(soft lockout only) if a heat call is cycled off for greater
than 2 seconds but less than 20 seconds.
The furnace control will not initiate a heat cycle during any
lockout condition. A call for compressor or continuous fan
will generally be responded to but control will display the
lockout error fault code instead of the “C” (for compressor)
or “F” (for Continuous fan).
FIVE-MINUTE LOCKOUT
A five minute “soft” lockout will be initiated if the low pressure switch fails to close after 60 seconds of continuous
inducer operation at the beginning of a normal heat cycle
(pressure switch proving period). The seven-segment display will display the appropriate fault. Lockout will automatically be reset after five minutes.
ONE-HOUR LOCKOUT
A one hour “soft” lock out will be initiated when:
Flame has not been detected after four igni-tion trials.
Flame has been lost for five times in one heatcall.
Undesired flame has been detected. The one-hour period will commence after flame is no
longer detected.
Dead Blower has been detected (main limitcircuit open for more than 150 seconds)
When voltage has unexpectedly been de-tected on the gas valve circuit and voltage
goes away when inducer is shut off.
If a
Water Sensed
condition is detected onceduring heat call (heat cycle terminated in response to fault) and then clears and then is
detected again within 5 minutes of the next
heat attempt (same heat call).
The seven-segment display will alternately display “10”
and the code number for the fault causing the lockout.
Lockout will automatically be reset after one hour.
HARD LOCKOUT
Three conditions shall cause a hard lockout:
1. The control senses an unspecified internal fault. Fault
code “93” is set and displayed. This lockout condition cannot be reset by cycling the heat call.
2. Voltage is detected unexpectedly on the gas valve contacts (welded relay) and will not clear by cycling
the inducer . Fault code “93” is set and displayed. This
lockout condition cannot be reset by cycling the heat call.
3. The furnace control will declare that the blower motor is
inoperable (dead) if the main limit control has been open
for more than 150 seconds. Gas heating is terminated.
However, the control continues to try to operate heating
for up to four attempts in case the blower motor starts
working again. If a dead blower has been declared four
times in one heat call, the furnace control enters a hardlockout. Fault code “61” is set and displayed. This lockout
condition CAN be reset by cycling the heat call.
REPLACING THE FURNACE CONTROL
In the event that the furnace control must be replaced, the
model data card must be removed from the original furnace control and retained with the furnace. A plastic tether
with a note wrapped around the tether is used to remind
the technician not to remove the card from the furnace.
Use this card to insert into the model data card connector
labeled P6 of the replacement control board. Failure to
save and connect the model data card properly to the replacement control may result in no operation or undesired
operation of the furnace.
When replacing the furnace control, be sure to match the
dipswitch settings of the original control on the replacement.
DO NOT CUT THE PLASTIC WIRE TIE USED AS A
TETHER TO THE ATTACHED MODEL DATA CARD.
DOING SO WILL DEFEAT THE PURPOSE OF RETAINING THE MODEL DATA CARD – WHICH COULD LEAD
TO A LOSS OF CRITICAL DATA NECESSARY TO OPERATE THE FURNACE. THE CARD MUST STAY WITH
THE FURNACE – EVEN WHEN THE FURNACE CONTROL (IFC) MUST BE REPLACED. NEVER USE A
CONTROL BOARD TAKEN FROM ANOTHER FURNACE
AS A REPLACEMENT CONTROL FOR THIS FURNACE.
FURNACE CONTROLS TAKEN FROM OTHER FURNACES MAY CONTAMINATE THE SYSTEM WITH THE
WRONG MODEL DATA WHICH CAN ONLY BE FIXED
BY REPLACING THE MODEL DATA CARD WITH THE
ORIGINAL MODEL DATA CARD FROM THE ORIGINAL
FURNACE OR A REPLACEMENT MODEL DATA CARD
DESIGNED FOR THE ORIGINAL FURNACE.
DIAGNOSING BLOWER MOTOR
ISSUES
If the main circulating blower motor will not operate when
it should, there are some different methods for diagnosing
the problem.
Page 75
75
DIAGNOSING BLOWER MOTOR ISSUES
1. MOTOR POWER AND COMMUNICATIONS ISSUES (FAULT CODE “68”)
Is the motor communicating properly with the furnace
control? If not, the fault code “68” will be displayed
any time there is a call for cooling, heating or continuous fan. To determine the cause of this issue, follow these steps:
A. Remove the line voltage connector from the
motor. This is the 5-pin connector. With the door
switch closed, verify that there is 115-120VAC between pins 4 and 5 of the connector (see photos
in Figure 45B). If no line voltage is detected,
check the wiring and correct the issue. Line voltage should be present at these pins any time the
furnace is powered. Make sure that the pins of the
connector are fully seated in the housing to ensure good contact with the connection at the
motor. When voltage is confirmed at these pins,
replace the connector on the motor.
B. Remove the motor control connector from the fur-
nace control at P5 and apply 24VAC to pins 3 & 4
(see photo). With the door switch closed (motor
powered) and 24VAC on pins 3 & 4, the motor
should start operating at 75% of capacity. If the
motor is operating at a good speed, it is likely not
the motor that is the problem. If the motor is not
operating, verify that the control wiring between
the motor and furnace control (to P5) is good and
that all the pins on both ends are fully seated. If
the wiring connections looks good, and the motor
still will not operate, the motor likely needs to be
replaced.
DIAGNOSTICS
FIGURE 45
LINE VOLTAGE AND LOW VOLTAGE CONNECTIONS TO THE COMMUNICATING MOTOR
AB
Diagnostics
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Page 76
76
Diagnostics
2. OVERSPEED OPERATION (CODE “66”)
Note: This code will only be displayed during the first
three minutes of blower operation and then only if
the call for fan is great enough to force the motor into
speed limit.
A. Is the duct work of the system restrictive or con-
fined? Or, maybe many (or all) of the supply registers are closed in the duct system. If so, the
motor may indicate that it is operating in power
limit under certain conditions by displaying code
“66”. Remove the restrictions or reconfigure the
duct work to avoid this code.
B. Is the motor set-screw not tightened to the motor
shaft? This may cause erratic motor operation
and cause the furnace to display a “66” fault code.
Further, airflow will be low or air may not be moving at all.
3. INTERNAL ERROR – MOTOR UNABLE TO OPERATE (FAULT CODE “61”)
If the blower motor is able to communicate with the
furnace control but is experiencing an internal issue
– such as overheating, the fault code “61” will be displayed. Internal overloading may reset once the
condition causing the problem has been removed.
However, it is likely that the motor will need to be replaced.
A. Is the motor wheel blocked by an obstruction? If
so, the motor may be in locked-rotor state and the
furnace control will report fault code “61”. Remove the obstruction and try to operate the motor
again. If the motor continues to fail, it may be
permanently damaged and may need to be replaced.
B. Is the motor overheating? If so, it may report an
overheat condition to the furnace control and the
control will report fault code “61”. Determine the
cause of overheating and repair. Try to operate
the motor again. If the motor continues to fail, it
may be permanently damaged and may need to
be replaced.
4. INTERNAL ERROR – MOTOR ABLE TO
OPERATE (FAULT CODE “60”)
This is a low-level fault that is not likely to be displayed often. Operation will continue as normal but
fault code will be displayed. Long-term permanent
damage to the motor is not expected.
DIAGNOSTICS
DIAGNOSING BLOWER MOTOR ISSUES
FIGURE 46
LOW VOLTAGE CONNECTION PIN DETAIL
*
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Page 77
77
FIGURE 47
DIAGNOSTICS FLOWCHART
Diagnostics
2-STAGE COMMUNICATING INTEGRATED
FURNACE CONTROL (IFC)
DIAGNOSTIC CHART
Be sure to note dip switch settings before troubleshooting.
1) For communicating systems, Remove communications
connections from the T-stat (E1, E2) and use a jumper wire
between R & W2 to set high stage gas heat. For legacy
systems ensure W2 & W1 are properly connected and make
sure both are energized w/ 240 AC after the heat call is placed.
2) Set FAN switch to “AUTO” on T -stat.
3) Set thermostat to call for heat (set temp. dif ferential to greater
than 10°F). (Comm. jumper W1 to R and W2 to R)
be displayed at “SSD’s” and should be on steady, if
4) “H” should
flashing check dip switches (Item “1”).
TSTA T = Thermostat.
IDM = Induced Draft Motor (or Inducer).
IFC = Integrated Furnace Control (or control board).
PS = Pressure Switch(es).
PFC = Power Factor Correction Choke.
SE = Spark Electrode (s).
SSD = Seven Segment Display of Furnace
COMM. = Communication.
I&O = Installation & Operation Instructions Manual.
Dual SSD’S “ON” ?
Is thermostat heat call present?
For 24 VAC (Non-Comm. T-stat., is 24 VAC on W1 and/or W2 of
IFC. H or h should be displayed at SSD’S. ?
control
DISCONNECT POWER BEFORE SERVICING.
SERVICE MUST BE BY A TRAINED,
QUALIFIED SERVICE TECHNICIAN.
“A Lower case H is displayed at IFC SSD’S” ?
IS
Capital “H ”
(pre-purge) IDM runs for 30 sec. at low speed?
Spark Electrodes (SE) Energize
Does Main Burner Light and stay lit
on Low?
ECM BLOWER “ON” DELAY
Does ECM blower start on Low heat
speed 15-20 seconds after burners light?
STEADY LOW HIGH
LOW HEAT CALL END
Apply the 2nd stage heat call
remains. Ensure 24 VAC to W1 & to W2
A capital “ H” should be displayed.
Does Gas valve switch to High Fire?
while low heat call
Is a faul
(After 10 Sec. a fault code will display anyway)
Lower case “h”
?
G0 T0
- Check all connections between I.F. C. & E .C .M . Motor.
- Check 24v to E .C .M . control (4pin connector, pin 1-4)
- Check Dip switch setting.
- Check P.F.C . choke. (if present)
- Check all wiring and connections to P. F.C choke.
- Check fau
- Check line voltage to motor (115VAC).
Note: IFC SSD’s will display “22 or 33”.
CHECK:
AIRFLOW - ensure no restrictions, such as dirty filter, b lower wheel,
dampers or closed registers, Etc. exist.
LIMITS - ensure goodwireandconnectionsbetween I. F. C. and all limits.
makes sure limits are not open when circulating air temperature is within
specific range.
ROLLOUTS - Ensure rolloutsorovertemperature limits donotneedtobe
reset. make sure no flame rollout in burner compartment due to blocked f lue
or heat exchanger or combustion restriction.
OVERFIRE - ensure furnaceisnotoverfired(tempriseisabovestated
range). Check gas valve, proper orifice size, gas presure
t code displayed at IFC?
H or h only
-Check line voltage at I.D.M.
-Check Wires And connections between I.D.M. and I.F.C.
-Ensure line voltage between P3, Pin 2 & P3, Pin 3 of I.F.C. (High IND Output).
-Check I.D.M. Capacitor.
Check t-stat, replace if
Check W2 & connections,
replace or repair as
PROBLEM
PERSISTS ?
I
For 1st 10 Sec. only
necessary.
necessary
Does IDM Run for 60 Sec. and then of f
for five minutes with fault
45, 46 or 57 displayed?
See I&O.
Does gas valve remain
energized?
lt codedispl ay,see“fault codes”inI& O. (ifpresent)
FAULT
Under ”Troubleshooting”
in I & O Manual
- See FAULT CODES under
I&O Manual.
Note: If good flameis not sensed a fault code
“11” or “13” will be displayed at SSD’s
Note: “12” is low
still operate well.
flame sense, furnace should
CHECK:
-Grounding on I.F.C . in p lace and continuity between screw and field
-installedground.
a
-Flame sense rod cl ean (clean if nessessary).
-Wire continunity between flame sense rod and Pin P2-7 on I.F.C .
-Flame carries across all burners, and
Is gas valve
remaining on Low
or de-energizing
completely?
CHECK:
- Fault codes at IFC SSD - see FAULT CODES under troubleshooting
in I&O manual.
- 24V Between IFC pins P2-5 & P2-4 of I .F.C .
- Make sure High heat call present at T-stat.
- T-stat wires and connections
“Troubleshooting” in
P2 - 6
NOTE: If IFC goes into lockout, shut of f main powertounit,wait30
seconds then reset power or removed heat call and re-establish.
?
all burners stay lit.
P2 - 4 on IFC.
Fault code
“45”, “46” or
“57” displayed
at SSD’s.
scotchbrite pad)
.
ST-A1 194-66-00
Page 78
78
Diagnostics
FIGURE 47 (cont.)
DIAGNOSTICS FLOWCHART
After B lower on delay, Does IDM switch to High speed
and remain at low speed after switching?
Does I . B. M. energize at High speed?
STEADY HIGH HEAT
Does I . B. M. shut off after 90 seconds? (plus s lew)
Remove power to furnace, open b lower compartment
and restore dip switches to original settings. Repl ace
bl ower door. Restore power to unit.
continue to operate at high
Does furnace
fire until T-stat satisfied or heat call
removed?
Remove heat call by setting
T-stat below room temp.
Does IDM Shut off after post purge?
- Check wire and a ll connections between I.F.C .and I.D .M
Check to make sure test mode dip switches are properly set.
Ensure T-stat not
switching to low fire or
test mode not timing out
(1 hour limit)
Double check - is heat call
completel y off at IFC?
Low
Fault code displ ayed?
See FAULT CODES under
troubelshooting in the I & O Manual
- Check all connections between IFC and ECM motor.
- Check 24V to ECM Motor. (low vol tage connector, pins 1 & 4)
- Check P.F.C . Choke. (except 1/2 HP motors)
- Check all wiring and connections
- Check fault code display and see “faul t codes” In I & O .
** System will attempt to light 4 times. Voltage Is present at gas valve for
only 7 seconds during each ignition trial. System will enter a 1 hour
lockout after 4 attempts.
REPEAT THIS SEQUENCE UNTIL TROUBLE- FREE OPERATION
PROBLEM PERSISTS
C
to P.F. C. choke.
ST-A1 194-66-00
Page 79
79
FIGURE 48
FOR MODELS WITH UT ELECTRONIC CONTROLS 1028-928 INTEGRATED FURNACE CONTROL AND DIRECT SPARK IGNITION
Wiring Diagram
5
4
3
IBM
2
1
POWER
$0/530-
123
4
P5-1
P5-2
P5-3
NEUTRAL
NEUTRAL
115 VAC
LINE VOLTAGE
24 VAC
120VAC
COM
24VAC
W1
S/A SENSOR
P5-4
C
V
TX
RX
FUSE
C
G
Y1
Y2
W2
PFC
120VAC
120VAC
NEUTRAL
B
R
HUM-STAT
P4-1
P4-2
CONTROL VOLTAGE
SENSOR
SUPPLY AIR
J-BOX
GND
P1-2
P1-4
P4-4
P2-3
MRLC MRLC
120VAC IN
NEUTRAL IN
EAC
P1-3
P1-1
P1-5
HALC
CONTACTS
LC
O
POWER
P1
P4
Y
R
COM
SEC
P2
SPARK
IGNITER
T1
L1
SUPPLY
BK
BK
BK
P3
W
W
INSTRUCTIONS TO
SEE INSTALLATION
PL-13 TO IBM
WIRE THERMOSTAT
Y
4-PIN CONNECTOR
IBM
5-PIN
PL-16 TO
R
R
BR
O/W
Y/PK
CONNECTOR
IBM
NEU
P5
W
BK
BK
W
G
BK
GND
PL-15
PL-14
PFC
BK
PL-12 TO IFC P5
4-PIN CONNECTOR
Y
BK
PBS
EAC
RELAY
P2-1
HPC
TO 115/1/60
BK
N
L
LOW SPEED
P3-1
P2-2
L
N
BK
W
BK
IDR
LGVR
P4-3
LPC
DISC
GND
EARTH
HIGH SPEED
P3-2
2-STAGE
FU
5-PIN
GND
RC
IDM
P3-3
HUMIDIFIER
NEUTRAL
FLMS
P2-7
GND
SE
SPARK IGNITER
GND
IGNITER VOLTAGE
WIRE COLORCODE
PR......PURPLE
G........GREEN
W.......WHITE
R........RED
O........ORANGE
GY......GRAY
Y........YELLOW
UPFLOW - HORIZONTAL
ELECTRICAL WIRINGDIAGRAM
IFC 80+
P1-4
GAS VALVE
HALC
GND
TO GND
CONNECTOR
HGVR
P2-5
P2-4
P2-6
HEATER
LOW
HIGH
G
PL-5
G
3-PIN
CONNECTOR
W
PL-1
TO P-1
G
G
W
4-PIN
2 STAGE ECM
GND
TO FURNACE
BR......BROWN
BL.......BLUE
BK......BLACK
CABINET
J - BOX
BK
PBS
SWITCH)
(BLOWER DOOR
IN DOOR BRACKET
3-PIN
PL-18
CONNECTOR
PL-3
3-PIN
TO P-3
ON IFC
CONNECTOR
PL-4
TO P-4
ON IFC
CONNECTOR
G-1021S044
ORIGINAL RELEASE
NO.:
8-5-14
DATE:
W/ ECM MOTOR & ECO NET
GAS FIRED, FORCED AIR FURNACE
CHECKED:APPROVED:
MODELED
= CHASIS GROUND
= EARTH GROUND
TWO STAGE 80 PLUS ECM
BLOWER INDUCED DRAFT
REV:PART NO.:
90-104961-0700
JHB
BY:
R
W
BK
PL-6
4-PIN
CONNECTOR
EMPTY
50K AND 75K MODELS
PL-7
IDM
4-PIN
CONNECTOR
O
SE
PL-6
5-PIN
CONNECTOR
100K, 125K MODELS
PL-7
5-PIN
CONNECTOR
R
7-PIN
GND
BK
W
IDM
R
O
W
PR
Y
R/G
BL
PR/W
PL-2
TO P-2
CONNECTOR
TO PS
TO HPC
GROMMET
TWIST-LOCK
TO FLMS
TO LGV
TO GVC
TO MGV
TO MRLC
W
CT
Y
R/BK
TO LC
R/B
R/B
HALC
W
EMPTY
EMPTY
R/W
Y
PR/BK
TO LPC
R
W
BK
TO LC
BLWR BLOWER RELAY HUM HUMIDIFIER OUTPUT PL PLUG
C COMMON IBM INDUCED BLOWER MOTOR PS PRESSURE SWITCH
CC COOLING CONTACTOR IDM INDUCED DRAFT MOTOR RC RUN CAPACITOR
CT CONTROL TRANSFORMER IDR INDUCED DRAFT RELAY SE SPARK ELECTRODE