Unitary products group 90% P DH Manual

035-19600-001 Rev. B (0204)
USER’S INFORMATION,
MAINTENANCE AND
SERVICE MANUAL
MODELS: 90% P*DH / G9T-DH / FG9-DH (Downflow)
EFFICIENCY
RATING
CERTIFIED
This product was manufactured
in a plant whose quality system
is certified/registered as being
in conformity with ISO 9001.
The manufacturer recommends that the user read all sec-
tions of this manual and keep the manual for future refer-
ence.
SECTION I: USER’S INFORMATION
SAFETY
1. The furnace area must be kept clear and free of combustible mate-
rials, gasoline and other flammable vapors and liquids.
2. Insulating materials may be combustible. The furnace must be
kept free and clear of insulating materials. The furnace area must
be examined when installed in an attic or other insulated space or
when insulation is added to be sure that the insulation material has
been kept away from the furnace.
3. The furnace needs air for combustion in order to operate properly
and safely. Do not block or obstruct air openings on the furnace,
air openings to the area where the furnace is installed, or spaces
around the furnace.
4. Follow the instructions exactly as shown on the OPERATING
INSTRUCTION LABEL or the Start-up and Shutdown Instructions
on Page 3 of this manual when lighting the furnace or turning the
furnace off.
5. Should the gas supply fail to shut off or if overheating occurs, shut
off the gas valve to the furnace before shutting off the electrical
supply.
6. Do not use this furnace if any part has been under water. A flood-
damaged furnace is extremely dangerous. Attempts to use the fur-
nace can result in fire or explosion. A qualified service agency
should be contacted to inspect the furnace and replace all gas
controls, control system parts, electrical parts that have been wet
or the furnace if deemed necessary.
FIRE OR EXPLOSION HAZARD - Failure to follow
safety warnings exactly could result in serious injury,
death, or property damage.
— Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any
other appliance.
— WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any
phone (including cell phone) in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
• If you cannot reach your gas supplier, call the fire
department.
— Installation and service must be performed by a
qualified installer, service agency or the gas sup-
plier.
CONTACT INFORMATION
• Go to website at www.york.com click on “contact”, then click on “contact form” and follow the instructions.
• Contact us by mail: York International Corperation
Consumer Relations
5005 York Drive
Norman, OK 73069
TABLE OF CONTENTS
CONTACT INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
USER’S INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
INSTRUCTIONS FOR EXAMINING THE FURNACE
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
HOW YOUR GAS FURNACE WORKS . . . . . . . . . . . . . . . . . . . . . .3
START-UP AND SHUTDOWN INSTRUCTIONS . . . . . . . . . . . . . . .3
Read the Instructions Below Before Trying to Start the
Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Operating Instructions: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
To Turn Off the Appliance: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
FURNACE USER MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . .4
Blower Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Removing Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Motor Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
SERVICE AND MAINTENANCE MANUAL . . . . . . . . . . . . . . . . . . . . .5
SAFETY SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
FURNACE MAINTENANCE SECTION . . . . . . . . . . . . . . . . . . . . . . .5
SEQUENCE OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Continuous Blower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Intermittent Blower - Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Heating Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Hot Surface Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
FURNACE CLEANING SECTION . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Burner Removal/Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Cleaning the Heat Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Cleaning the Secondary Heat Exchanger . . . . . . . . . . . . . . . . . . .6
Cleaning the Vent / Air Intake System . . . . . . . . . . . . . . . . . . . . . .6
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
FURNACE CONTROL DIAGNOSTICS . . . . . . . . . . . . . . . . . . . . . . .6
REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
FIELD INSTALLED ACCESSORIES - NON-ELECTRICAL . . . . . .10
REPLACEMENT PART CONTACT INFORMATION . . . . . . . . . . . . .10
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
LIMITED WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

035-19600-001 Rev. B (0204)
2Unitary Products Group
7. NEVER . . .Store flammable materials of any kind near your fur-
nace. Gasoline, solvents, and other volatile liquids should be
stored only in approved containers outside your home. These
materials vaporize easily and are extremely dangerous.
8. NEVER . . .Store cleaning materials near your furnace. Materials
such as bleaches, detergents, powdered cleansers, etc., can
cause corrosion of the heat exchangers.
9. NEVER . . . Use the area around your furnace as a storage area
for items which could block the normal flow of air. This flow of air is
required for ventilation of the various furnace components.
INSTRUCTIONS FOR EXAMINING THE FURNACE
INSTALLATION
It is the owner’s responsibility to ensure that an annual inspection of the
entire heating portion of the unit is made by a qualified service agency.
1. Examine the heat exchanger, through a field installed access
panel located on the supply air plenum. Visually examine the exte-
rior sections of the vent/combustion air piping and the vent con-
nectors to be sure that they are physically sound without holes
without excessive corrosion.
2. Examine the vent pipe making sure it is in firmly place, that it
slopes slightly upward and is physically sound without holes and
all of the connections are secure.
3. Examine the return-air duct connections to make sure they are
physically sound, sealed to the furnace casing, and the ducts ter-
minate outside the space containing the furnace.
4. Examine the furnace casing making sure the physical support is
sound without sagging, cracks or gaps. Examine the furnace base
making sure it is physically sound without cracks, gaps or sagging
and has a good seal.
5. Examine the furnace casing for obvious signs of deterioration.
6. Examine the burner flames to make sure they are in good adjust-
ment. Refer to the pictorial sketch shown in Figure 2 as a compari-
son to the actual flame.
7. Examine the furnace as outlined above in steps “1 - 6” before
each heating season. Use Figure 3 for visual reference.
FIGURE 1: Component Locations
FIRE OR EXPLOSION HAZARD
This furnace is designed and approved for use with Nat-
ural Gas and (LP) Propane Gas ONLY. DO NOT BURN
ANY LIQUID FUEL OR SOLID FUEL IN THIS FURNACE.
Burning any unapproved fuel will result in damage to the
furnace heat exchanger, which could result in Fire, Per-
sonal Injury, and/or Property Damage.
BURNER BOX
GAS VALVE
VENT PIPE
INDUCER
ASSEMBLY
CONTROL
BOARD
PRESSURE
SWITCH
BLOWER
INDUCER MOTOR
TRANSFORMER DOOR SAFETY
SWITCH
HOT SURFACE
IGNITER
BURNER BOX
COMBUSTION
AIR INLET
FLAME
LIMIT SWITCH
SENSOR
FIGURE 2: Burner Flame Drawing
COMBUSTION AIR INTAKE
BURNER FLAME
GAS MANIFOLD
INNER FLAME
CONES
MAIN GAS BURNER
COMBUSTION
AIR DIFFUSER
FIGURE 3: Furnace Examination Checkpoints
REMOVE THIS
EXAMINE
FURNACE
CASING
EXAMINE THE INTERNAL AND
EXAMINE RETURN AIR
32
6
4
DUCT CONNECTION
1
EXTERNAL VENT PIPES
2
PANEL TO
EXAMINE THE
BURNER FLAMES
EXAMINE
FURNACE
CASING
4
REMOVE THIS
PANEL TO
EXAMINE VENT
PIPE
PLACE A FIELD
INSTALLED ACCESS
PANEL LOCATED IN THE
DOWNFLOW PLENUM
TO EXAMINE THE
HEAT EXCHANGER

035-19600-001 Rev. B (0204)
Unitary Products Group 3
HOW YOUR GAS FURNACE WORKS
Your furnace is a very easy appliance to take for granted. Season after
season, it sits there in your home, keeping you warm and comfortable.
For this reason, you may never have given much thought to the way
your furnace operates. In order to get the safest and most efficient oper-
ation from your furnace, you should understand how your furnace does
its job.
When you set your thermostat to provide more heat in your home, you
are starting the heating cycle of the furnace. First, the inducer motor
starts to purge the heat exchanger of any remaining gases. Next, the
hot surface igniter glows and after a warm-up period the gas valve
opens and ignition occurs. A short time later, the blower starts and dis-
tributes the warm air throughout the home. When the temperature set-
ting on your thermostat is reached, the gas valve closes, the main
burners are turned off, and the blower continues to run until the remain-
ing warm air in the system is distributed. When the blower stops, the
heating cycle has ended.
START-UP AND SHUTDOWN INSTRUCTIONS
Read the Instructions Below Before Trying to Start the
Furnace
A. This appliance does not have a pilot. It is equipped with an ignition
device which automatically lights the burner. Do not try to light the
burner by hand.
B. BEFORE OPERATING; smell all around the appliance area for
gas. Be sure to smell next to the floor because some gas is
heavier than air and will settle on the floor.
C. Use only your hand to push the gas control switch to the “on” posi-
tion. Never use tools. If the switch will not operate by hand, don’t
try to repair it, call a qualified service technician. Force or
attempted repair may result in a fire or explosion.
D. Do not use this appliance if any part has been under water. Imme-
diately call a qualified service technician to inspect the appliance
and to replace any part of the control system and any gas control,
which has been under water.
Operating Instructions:
1. STOP! Read the safety information above.
2. Set the thermostat to the lowest setting.
3. Turn off all electric power to the appliance.
4. Remove burner access panel.
5. Move gas control switch to the “OFF” position. Do not force.
6. Wait five (5) minutes to clear out any gas. If you then smell gas,
STOP! Follow “B” in the safety information above. If you don’t
smell gas, go to next step.
7. Move gas control switch to the “ON” position. Do not force.
8. Replace burner access panel.
9. Turn on all electric power to the appliance.
10. Set thermostat to the desired setting. Burner will light, which may
take 30-60 seconds.
11. After three (3) trials for ignition, if the appliance will not operate fol-
low the instructions, “TO TURN OFF THE APPLIANCE” and call
your service technician or gas supplier.
To Turn Off the Appliance:
1. Set the thermostat to lowest setting.
2. Turn off all electric power to the appliance if service is to be per-
formed.
3. Remove burner access panel.
4. Move gas control switch to the “OFF” position.
5. Replace burner access panel.
NOTE: The spring-loaded safety cut-off switch, mounted on the blower
deck, behind the indoor fan access panel will automatically cut
off the electrical power supply to the furnace when the blower
panel is removed. As a safety precaution, all electrical power
and the gas supply to the furnace should be turned off before
servicing.
FURNACE USER MAINTENANCE
If you do not follow these instructions exactly, a fire or
explosion may result causing property damage, personal
injury, and/or loss of life.
Should overheating occur, or the gas valve fail to shut off,
turn the external manual gas valve in the gas supply line to
the furnace to the “off” position and let the furnace cool off
before shutting off the electrical power supply. Refer to
Figure 4.
FIGURE 4: Gas Valve - White Rodgers
FIGURE 5: Gas Piping
Before proceeding, be sure the area is well ventilated. Turn
the thermostat OFF. If the blower is running, wait until it
stops automatically. Turn OFF the gas and electrical power
supplies to the furnace. Check all metal parts and surfaces
to be sure they have cooled to room temperature before
you begin.
OFF
ON
OUTLET
PRESSURE
PORT
OUTLET
MAIN REGULATOR
ADJUSTMENT
ON/OFF
SWITCH
INLET
PRESSURE
PORT
WRENCH
BOSS
INLET
DRIP
LEG
GROUND JOINT UNION
MAY BE INSTALLED
INSIDE OR OUTSIDE UNIT.
EXTERNAL MANUAL
SHUTOFF VALVE
TO GAS
SUPPLY
TO GAS
SUPPLY

035-19600-001 Rev. B (0204)
4Unitary Products Group
Blower Care
Even with good filters properly in place, blower wheels and motors will
become dust laden after long months of operation. The entire blower
assembly should be inspected annually. If the motor and wheel are
heavily coated with dust, they can be brushed and cleaned with a vac-
uum cleaner. If the blower cannot be properly cleaned without removing
it from the furnace, then this service must be performed by a qualified
service agency..
Air Filters
The filters should be checked every 3 months. On new construction,
check the filters every week for the first four weeks and every three
weeks after that, especially if the indoor fan is running continuously.
When replacing the filter(s), refer to Table 1 to be sure you install the
right size filter for your furnace. Dirty filters greatly restrict the flow of air
and may cause damage to the moving parts of the furnace. If the filters
become clogged the heat exchangers and blower motor could overheat
resulting in a potentially dangerous situation.
Never operate your furnace without a suitable air filter.
Removing Filters
Most downflow furnaces have their filters located on the top of the fur-
nace in an external filter rack. To check filters you should:
1. Follow the instructions to turn off the appliance before servicing.
2. Filters are installed in the return air plenum above the blower
assembly. An “A” frame assembly supports the filters. Lift the filter
slightly and remove for service.
3. Follow the instructions “HOW TO CLEAN YOUR FURNACE’S FIL-
TER”.
4. Reverse the procedure to reinstall filters.
5. Follow the operating instructions to place appliance in operation.
Externally Mounted Air Filters
Some installations may have the air filter in a rack attached to the cas-
ing of the furnace or placed in the return air duct. You can gain access
to the filter by pulling on the door or unscrewing the retaining screw,
then slide the filter(s) out of its channel. Replace throw away filter(s)
with the same size new filter(s). Throw away filter(s) may be replaced
with cleanable filter(s) at this time. Cleanable filter(s) may be cleaned as
described in the manufacturer instructions or as described below and
then re-installed.
How to Clean your Filter
High-velocity filters may be cleaned with a vacuum cleaner or washed
with a garden hose. Be sure to shake off excess water and allow filter to
completely dry before re-installing the filter.
To replace the filter after cleaning you must do the following:
1. Slide filter into place.
2. Snap the door on or place the door in position and tighten the
retaining screws, if provided.
3. Make sure the door is secure to the end of the filter rack.
4. For filter grills, place the filter into the grill, close the grill cover and
tighten the retaining screw.
Every time the filters are changed the following items should be visually
inspected:
• Check combustion air and vent pipe for blockage or leakage.
• Check all components to be sure they are in good condition and
that there are no obvious signs of deterioration.
• Check the drain lines to make sure there are no cracks or leaks.
• Check for dirt or lint on any surfaces or on components. Do not try
to clean any of the surfaces or components. Cleaning of the fur-
nace and its components must be done by a qualified service pro-
fessional.
If, during the inspection of your furnace, you find any of the following
conditions:
• Excessive amounts of dust and lint on components.
• Damaged or deteriorated components or surfaces.
• Leaks or blockage in the vent pipe passages.
• Water on any surface inside or outside of the furnace.
Do not operate the furnace. Call a certified dealer / qualified service
agency to check and / or clean your furnace, or for more information if
you have questions about the operation of your furnace.
If all components appear to be in good operating condition, replace the
front panels. Turn ON the gas and electrical power supplies to the fur-
nace, and set thermostat to the desired temperature.
Motor Lubrication
The motors in these furnaces are permanently lubricated, and do not
require periodic oiling.
Make sure you DO NOT move the clip on weight on the
indoor fan wheel when cleaning the wheel. This weight is
used to balance the wheel. Moving the weight will cause
the fan wheel to vibrate.
FIGURE 6: Filter Rack Assembly and Attachment
A
A
FILTER RACK
(FACTORY SUPPLIED)
RACK AND FILTERS SECURED
INSIDE BLOWER SECTION
FOR SHIPMENT
DUCTWORK
FILTERS
FILTER
RACK FH
CROSS SECTION A-A
(WITH PLENUM AND FILTERS)
NOTE: FILTER ACCESS THRU
DUCTWORK MUST BE PROVIDED
FOR REMOVAL AND CLEANING
CASING SIZE DIMENSION FH
16-1/4
22-1/4
26-1/4
12-3/4
11
8-1/4
BRANCH
DUCTS

035-19600-001 Rev. B (0204)
Unitary Products Group 5
SECTION II: SERVICE AND MAINTENANCE
MANUAL
SAFETY SECTION
The following safety rules must be followed when servicing the
furnace.
FURNACE MAINTENANCE SECTION
The furnace should be cleaned and adjusted by a certified dealer or
qualified service contractor once a year or before the start of every
heating season. The following items must be cleaned and serviced or
replaced if there are signs of deterioration.
1. The vent terminal screen (if applicable).
2. The furnace vent and combustion air intake passageways. Should
it be necessary to service the vent/air intake system, the manufac-
turer recommends this service be conducted by a qualified service
agency. The operation of this appliance requires the reassembly
and resealing of the vent/air intake system.
3. The furnace burners, ignitor and flame sensor.
4. The condensate collection and disposal system. If any disassem-
bly of components containing flue or vent gases is required, a
qualified service agency must perform the service.
SEQUENCE OF OPERATION
The following describes the sequence of operation of the furnace. Refer
to Figure 1 for component location.
Continuous Blower
Cooling/heating thermostats have a fan switch that has an ON and
AUTO position. In the ON position the thermostat circuit is completed
between terminals R and G. The motor will operate on the speed tap
wire that is connected to the cooling terminal on the control board. To
obtain a constant air circulation at lower flow rate, change the high-
speed wire to either the medium speed wire or the low speed wire.
Intermittent Blower - Cooling
Cooling/heating thermostats have a fan switch that has an ON and
AUTO position. In the AUTO position the thermostat circuit is completed
between terminals R and G when there is a call for cooling. The motor
will operate on the speed tap wire that is connected to the cooling termi-
nal on the control board. The fan off setting is fixed at 60 seconds to
improve cooling efficiency.
Heating Cycle
When the thermostat switch is set on HEAT and the fan is set on AUTO,
and there is a call for heat, a circuit is completed between terminals R
and W of the thermostat. When the proper amount of combustion air is
being provided, the pressure switch will close, the ignition control pro-
vides a 17-second warm-up period, the gas valve then opens, the gas
starts to flow, ignition occurs and the flame sensor begins its sensing
function. The blower motor will energize 30 seconds after the gas valve
opens, if a flame is detected. Normal furnace operation will continue
until the thermostat circuit between R and W is opened, which causes
the ignition system and gas valve to de-energize and the burner flames
to be extinguished. The vent motor will operate for 15 seconds and the
blower motor will operate for the amount of time set by the fan-off delay
jumper located on the control board. See Figure 7. The heating cycle is
complete, and ready for the start of the next heating cycle.
If the flame is not detected within 2 seconds of the gas valve opening,
the gas valve is shut off and a retry operation begins. If the flame is lost
for 2 seconds during the 10-second stabilization period, the gas valve is
shut off and a retry operation begins. During a retry operation, the vent
motor starts a 15 second inter-purge and the ignitor warm-up time is
extended to 27 seconds. If the flame is established for more than 10
seconds after ignition during a retry, the control will clear the ignition
attempt (retry) counter. If three retries occur during a call for heat, the
furnace will shut down for one hour. If at the end of the one hour shut
down there is a call for heat, the furnace will initiate a normal start cycle.
If the problem has not been corrected the furnace will again lockout
after three retries.
TABLE 1:
Filter Sizes
Input / Output
BTU/H (kW) CFM (cm/m) Cabinet Size Filter Size (in) Filter Size (cm)
(in) (cm)
40/37 (11.71/10.84) 1000 (28.32) 14 1/2" (A) 36.83 (A) 14 x 20 35.6 x 50.8
60/55/ (17.57/16.10) 1000 (28.32) 17 1/2" (B) 44.45 (B) 14 x 20 35.6 x 50.8
80/75/ (23.42/21.96) 1200 (33.98) 17 1/2" (B) 44.45 (B) 14 x 20 35.6 x 50.8
80/75/ (23.42/21.96) 1600 (45.31) 21" ( C ) 53.34 (C) 14 x 20 35.6 x 50.8
100/95 (29.28/27.82) 1400 (39.64) 21" ( C ) 53.34 (C) 14 x 20 35.6 x 50.8
100/95 (29.28/27.82) 2000 (56.63) 21" ( C ) 53.34 (C) 14 x 20 35.6 x 50.8
120/112/ (35.14/32.80) 2000 (56.63) 24 1/2" (D) 64.77 (D) 14 x 20 35.6 x 50.8
ELECTRIC SHOCK, FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, and death or property damage.
• Before servicing, disconnect all electrical power to the fur-
nace.
• When servicing controls, label all wires prior to discon-
necting. Reconnect wires correctly.
• Verify proper operation after servicing.
FIGURE 7: Typical Heat/Cool Speed Tap Connections
RED-LOW SPEED
BLU-MEDIUM SPEED
BLK-HIGH SPEED MOTOR LEADS
BLK
BLU
RED
60
180
120
FAN OFF
ADJUSTMENT
SWITCHES
COOL
HEAT
PARK
PARK
LINE
XM
90

035-19600-001 Rev. B (0204)
6Unitary Products Group
A momentary loss of gas supply, flame blowout, or a faulty flame probe
circuit will result in a disruption in the flame and be sensed within 1.0
second. The gas valve will de-energize and the control will begin a recy-
cle operation. A normal ignition sequence will begin after a 15 second
inter-purge. If during the five recycles the gas supply does not return, or
the fault condition is not corrected the ignition control will lockout for 60
minutes.
During burner operation, a momentary loss of power for 50 milliseconds
or longer will de-energize the gas valve. When the power is restored,
the gas valve will remain de-energized and the ignition sequence will
immediately restart.
Hot Surface Ignition System
FURNACE CLEANING SECTION
NOTE: The cleaning operations listed below must be performed only by
a qualified service agency.
Burner Removal/Cleaning
The main burners should be checked periodically for dirt accumulation.
If cleaning is required, follow this procedure:
1. Turn off the electrical power to the unit.
2. Turn off the gas supply at the external manual shut-off valve and
loosen the ground union joint.
3. Remove the upper access panel and remove the burner box cover.
4. Disconnect wires from flame sensor, rollout switch and HSI igniter.
Remove igniter carefully, as it is easily broken.
5. Remove the screws that hold the burner box assembly to the vest
panel and remove the assembly.
6. Remove burners from the burner assembly.
7. Burners may be cleaned by rinsing in hot water.
8. Reassemble the burners in the reverse order.
Cleaning the Heat Exchanger
Follow Steps 1-5 above.
1. Remove the upper cover plate at the top of the furnace. Remove
the internal baffle.
2. The upper portion of the heat exchanger is now exposed.
3. With a long flexible wire brush, clean inside each tube at both the
top and bottom. The brush must pass around the rear heat
exchanger tubes and then vacuum loose the scale and dirt from
each tube.
4. Clean - vacuum all burners.
5. Replace all components in reverse order. Reconnect all wiring.
6. Restore electrical power and gas supply to the furnace.
7. Check furnace operation. Follow operating instructions.
Cleaning the Secondary Heat Exchanger
1. Follow steps 1 - 8 under cleaning the Heat Exchanger.
2. Remove the vent piping from the vent blower housing. Disconnect
the drain lines from the vent blower housing and from the conden-
sate drain pan. Remove the vent blower housing blower and the
condensate pan. The turbulators can then be gently removed from
the secondary heat exchanger.
3. Using a stiff wire brush, remove the loose scale or soot from each
tube.
4. Vacuum the secondary heat exchanger.
5. Finish the cleaning procedure by following Steps 5 thru 7 under
cleaning the Heat Exchanger.
Cleaning the Vent / Air Intake System
Should it be necessary to service the vent / air intake system, the man-
ufacturer recommends this service be conducted by a qualified service
agency.
The operation of this appliance requires the reassembly and resealing
of the vent / air intake system as specified in the “Combustion Air and
Vent System” located in the Installation Manual.
TROUBLESHOOTING
The following visual checks should be made before troubleshooting:
1. Check to see that the power to the furnace and the ignition control
module is ON.
2. The manual shut-off valves in the gas line to the furnace must be
open.
3. Make sure all wiring connections are secure.
4. Review the sequence of operation. Start the system by setting the
thermostat above the room temperature. Observe the system’s
response. Then use the troubleshooting section in this manual to
check the system’s operation.
FURNACE CONTROL DIAGNOSTICS
The furnace has built-in, self-diagnostic capability. If a system problem
occurs, a blinking red LED shows a fault code. It is located behind a
clear view port in the blower compartment door. DO NOT remove the
furnace blower compartment panel OR turn off furnace power, as either
action will clear the control’s memory of the fault.
The control continuously monitors its own operation and the operation
of the system. If a failure occurs, the LED will indicate the failure code. If
the failure is internal to the control, the light will stay on continuously. In
this case, the entire control should be replaced, as the control is not
field repairable.
Flash sequence codes 1 through 11 are as follows: LED will turn “on” for
one second and “off” for one second. This pattern will be repeated the
number of times equal to the code. For example, six “on” flashes equals
a number 6 fault code. All flash code sequences are broken by a 2 sec-
ond “off” period.
HOT SURFACE IGNITION SYSTEM
Do not attempt to light this furnace by hand (with a
match or any other means). There may be a potential
shock hazard from the components of the hot surface
ignition system. The furnace can only be lit automatically
by its hot surface ignition system.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and danger-
ous operation. Verify proper operation after servicing.
Never bypass pressure switch to allow furnace opera-
tion. To do so will allow furnace to operate under poten-
tially hazardous conditions.
Do not try to repair controls. Replace defective controls
with UPG Source 1 Parts.
Never adjust pressure switch to allow furnace operation.

035-19600-001 Rev. B (0204)
Unitary Products Group 7
CONTINUOUS FLASH: This indicates that flame was sensed when
there was not a call for heat. With this fault code the control will turn on
both the inducer motor and supply air blower. A gas valve that leaks
through or is slow closing would typically cause this fault.
2 FLASHES: This indicates that the normally open pressure switch
contacts are stuck in the closed position. The control confirms these
contacts are open at the beginning of each heat cycle. This would indi-
cate a faulty pressure switch or miswiring.
3 FLASHES: This indicates the normally open pressure switch contact
did not close at the beginning of the heat cycle. This could be caused
by a number of problems; faulty inducer, blocked vent pipe, broken
pressure switch hose or faulty pressure switch.
4 FLASHES: This indicates that a primary or auxiliary limit switch has
opened its normally closed contacts. With this fault code the control will
operate the supply air blower and inducer. This condition may be
caused by; dirty filter, improperly sized duct system, incorrect blower
speed setting, incorrect firing rate or faulty blower motor.
5 FLASHES: This fault is indicated if the normally closed contacts in the
rollout switch opens. The rollout control is manually reset. If it has
opened, check for proper combustion air, proper inducer operation, and
primary heat exchanger failure or burner problem. Be sure to reset the
switch after correcting the failure condition.
6 FLASHES: This indicates that after the unit was operating, the pres-
sure switch opened 4 times during the call for heat. If the main blower is
in a “Delay on” mode it will complete it, and any subsequent delay off
period. The vent motor continues to operate until the pressure switch
re-closes or a call for heat is removed.
7 FLASHES: This fault code indicates that the flame could not be
established. This no-light condition occurred 3 times (2 retries) during
the call for heat before locking out. Low gas pressure, faulty gas valve,
faulty hot surface ignitor or burner problem may cause this.
8 FLASHES: This fault is indicated if the flame is lost 5 times (4 recy-
cles) during the heating cycle. This could be caused by low gas pres-
sure or faulty gas valve.
9 FLASHES: Indicates reversed line voltage polarity. Both heating and
cooling operations will be affected. Check polarity at furnace and
branch.
11 FLASHES: This fault will be indicated if the rollout jumper wire con-
nection is broken, the control must be replaced. This fault may also
occur in installations where an improper ground is present. Prior to
replacing control, verify that unit is properly grounded.
STEADY ON: This fault occurs if the gas valve is energized when there
is no call for heat. If this happens the vent motor is energized and will
remain energized for 5 seconds or until the fault clears itself at which
point the vent motor de-energizes. This failure is counted as a recycle.
Check the gas valve and control for proper operation.
60-MINUTE AUTOMATIC RESET FROM LOCKOUT: This control
includes a “watchdog” type circuit that will reset from a lockout condition
after 60 minutes. Operational faults 1,6,7,8 and Steady On will be reset.
This provides protection to an unoccupied structure if a temporary con-
dition exists causing a furnace malfunction. An example would be a low
incoming gas supply pressure preventing unit operation. When the gas
pressure is restored, at some point the “watchdog” would restart the
unit and provide heat for the house.
NOTE: If a flame is detected the control flashes the LED for 1/8 of a
second and then enters a flame stabilization period.
IGNITION CONTROL (P/N 031-01267-001)
Normal flame sense current is approximately
3.7 microamps DC (µa)
Low flame signal control lockout point is
0.9 microamps DC (µa)
FIGURE 8: Furnace Control Event Schedule
Thermostat Calling for Heat Thermostat Satisfied
(Seconds)
THERMOSTAT
INDUCER
IGNITOR
MAIN VALVE
HUMIDIFIER
ELECTRONIC
AIR CLEANER
CIRCULATING
BLOWER
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
OFF
OFF
OFF
OFF
ON
ON
ON
OFF
OFF
OFF
OFF
OFF
OFF
OFF
15 Sec.
Post
Purge
Fan on Delay
30 Seconds
0217 22 52 0
60, 90, 120, 180 SEC.
Selectable Fan Off Delay

035-19600-001 Rev. B (0204)
8Unitary Products Group
SECTION III: REPLACEMENT PARTS LIST
15
16
1
17
3
7A
13
10
11
14
5
8
12
9
2
7
6
6
24
27
26
35
38
34
32
33
25
36
22
37
21
20
28
29
23
31
30
18
19
51
63
43
53
59
57
58
55
39
41
52
45
47
62
60
42
48
49
50
44

035-19600-001 Rev. B (0204)
Unitary Products Group 9
ITEM DESCRIPTION
MOTOR
1 MOTOR, DIRECT DRIVE BLOWER
2 MOTOR, VENTOR ASS’Y
ELECTRICAL
3 CAPACITOR (7.5MFD/370V)
4
5 CONTROL, HIGH LIMIT
6 CONTROL, FLAME ROLL OUT(2 Req,d)
7 CONTROL, FURNACE
7A FUSE
8IGNITER
9 SENSOR, FLAME
10 SWITCH, AIR PRESSURE [1LP]
11 SWITCH, AIR PRESSURE [2LP]
12 SWITCH, DOOR
13 TRANSFORMER
14 VALVE, GAS
15 CONTROL, LIMIT (Blower)
AIR MOVING
16 HOUSING, BLOWER
17 WHEEL, BLOWER
FABRICATED PARTS
18 BAFFLE, AIR (LH Recoup.Coil)
19 BAFFLE, AIR (RH Recoup.Coil)
20 BURNER, MAIN GAS
21 COIL, SECONDARY HEAT EXCHANGER
22 DECK, BLOWER (Rear)
23 DECK, FRONT
24 HEAT EXCHANGER ASS’Y (Primary)
25 MANIFOLD, GAS
26 PANEL, BASE
27 PAN, CONDENSATE
28 PANEL, BURNER BOX (Bottom)
29 PANEL, BURNER BOX (Front)
30 WRAPPER, BURNER BOX
31 COVER, HEAT EXCHANGER
32 PANEL, FRONT (Blower)
33 PANEL, FRONT (Burner)
34 PANEL, TOP
35 SUPPORT, BURNER
36 WRAPPER, CABINET (Insulated) P3D
WRAPPER, CABINET G9T, FG9
37 PANEL, VESTIBULE (Lower)
38 PLUG, WINDOW, CLEAR - .875”
MISCELLANEOUS
39 COLLAR, AIR INTAKE (Burner Box)
40 FILTER, AIR (2 Req’d) P3D, G9T
FILTER SIZE
41 GASKET, AIR INTAKE
42 GASKET, COMBUSTION BLOWER
43 GASKET, CONDENSATE PAN
44 GASKET, BURN BOX TO VEST PANEL
45 GROMMET, MANIFOLD SEAL
46
47 HANDLE, DOOR
48 ISOLATOR, TUBE (3 Req’d)
49 ISOLATOR, WASHER (3 Req’d)
50 ISOLATOR, SLEEVE (3 Req’d)
51 MOUNT, MOTOR
52 ORIFICE, BURNER (Natural #45)
53 PLUG, WINDOW,CLEAR - 1.5”
54 BRACKET, FILTER P3D, G9T
55 TRAP, CONDENSATE
56 WIRING DIAGRAM
57 HOSE, INDUCER DRAIN
58 HOSE, RAIN GUTTER DRAIN
59 HOSE, CONDENSATE DRAIN
60 BRACKET, IGNITOR
61 HOSE, CONDENSATE TRAP
62 PIPE VENT (Outer)
63 PIPE EXHAUST VENT (Inner)
64 DRAIN, INDUCER
65 DRAIN, INDUCER
66 DRAIN, RAIN GUTTER
67 DRAIN, CONDENSATE PAN
ITEM DESCRIPTION
NOTE: *Not Shown
New replacement parts shown in bold face type at the first printing of parts list dated 11/02.
Major components and suggested stocking items are shown with shaded item number.

035-19600-001 Rev. B (0204)
10 Unitary Products Group
FIELD INSTALLED ACCESSORIES - NON-ELECTRICAL
FIELD INSTALLED ACCESSORIES - NON ELECTRICAL
MODEL NO. DESCRIPTION USED WITH
1NP0347 PROPANE (LP) CONVERSION KIT ALL MODELS
1CT0302 CONCENTRIC INTAKE/VENT 2” 40, 60, 80, 100 MBH
1CT0303 CONCENTRIC INTAKE/VENT 3” 120 MBH
1PS0306
HIGH ALTITUDE PRESSURE SWITCH KIT
(Does Not Include Orifices) FOR APPLICATION INFORMA- TION SEE FORM 650.75-N2.1V
1PS0307
1PS0308
1PS0309
1PS0310
ICB0314
COMBUSTIBLE FLOOR BASE FOR DOWNFLOW UNITS
14-1/2” CABINETS
1CB0317 17-1/2” CABINETS
1CB0321 21” CABINETS
1CB0324 24-1/2” CABINETS
1BR0314
EXTERNAL FILTER RACK WITH HIGH VELOCITY FILTER FOR
HORIZONTAL APPLICATION
14-1/2” CABINETS
1BR0317 17-1/2” CABINETS
1BR0321 21” CABINETS
1BR0324 24-1/2” CABINETS
1NK0301 CONDENSATE NEUTRALIZER KIT ALL MODELS
REPLACEMENT PART CONTACT INFORMATION
This is a generic parts list. To request a complete parts list, refer to the contact information below:
• Visit our website at www.source1parts.com for the following information:
1. Search for a part or browse the catalog.
2. Find a dealer or distributor.
3. Customer Service contact information.
a. Click on the “Brand Links” button
b. Click on the “Customer Service” button
• You can contact us by mail. Just send a written request to:
York International
Consumer Relations
5005 York Drive
Norman, OK 73069

035-19600-001 Rev. B (0204)
Unitary Products Group 11
SECTION IV: WIRING DIAGRAM
FIGURE 9: Wiring Diagram

Subject to change without notice. Printed in U.S.A. 035-19600-001 Rev. B (0204)
Copyright © by Unitary Products Group 2004. All rights reserved. Supersedes: 035-19600-001 Rev. A (1103)
Unitary 5005 Norman
Products York OK
Group Drive 73069
Limited Warranty
UPG warrants this product to be free from defects in factory workmanship and material under normal use and service and will, at its option, repair or replace
any parts that prove to have such defects according to the terms outlined below. This warranty covers only the equipment described by the Product Model
Number and Serial Number listed on the Warranty Registration Card.
UPG warrants the primary heat exchangers in the product to be free from defects in factory workmanship and material under normal use and service and will at
its option, repair or furnish a replacement heat exchanger, either new or reconditioned, that meets the intended fit, use and function of the original heat
exchanger for any heat exchanger furnished by UPG which proves to have such defects within the duration of warranty coverage. Alternatively, UPG may, at its
option, extend a replacement allowance to be applied toward the purchase of a new furnace or packaged unit marketed by UPG. The exact amount of the
allowance will be determined at the discretion of UPG, based upon current market conditions, but in no case shall this allowance exceed thirty (30) percent of
the original consumer purchase price of the furnace, excluding such items as ductwork, wiring, piping and installation costs. UPG shall have no responsibility
hereunder for installation, shipping, handling or other charges except as specifically provided herein.
For your benefit and protection, return the Warranty Registration Card to UPG promptly after installation. This will initiate the warranty period and allow us to
contact you, should it become necessary. In the absence of a recorded Warranty Registration Card, the warranty period will begin upon product shipment from
UPG.
This warranty extends only to the original consumer purchaser and is non-transferable. For this warranty to apply, the product must be installed according to
UPG recommendations and specifications, and in accordance with all local, state, and national codes; and the product must not be removed from its place of
original installation. The warranty period for repair or replacement parts provided hereunder shall not extend beyond the warranty period stated below.
UPG strongly recommends regular periodic preventative maintenance on this equipment. The person most familiar with the equipment in your HVAC system is
a UPG dealer. The UPG dealer can ensure your maintenance program meets the conditions of the "UPG Warranty", maximize the efficiency of the equipment.
This warranty applies only to products installed in the United States and Canada.
EXCLUSIONS
This warranty does not cover any:
1. Shipping, labor, or material charges.
2. Damages resulting from transportation, installation, or servicing.
3. Damages resulting from accident, abuse, fire, flood, alteration, or acts of God (tampering, altering, defacing or removing the product serial number will
serve to void this warranty).
4. Damages resulting from use of the product in a corrosive atmosphere.
5. Damages resulting from inadequacy or interruption of electrical service or fuel supply, improper voltage conditions, blown fuses, or other like damages.
6. Cleaning or replacement of filters.
7. Damages resulting from failure to properly and regularly clean air and/or water side of condenser and evaporator.
8. Damages resulting from: (I) freezing of condenser water or condensate; (II) inadequate or interrupted water supply; (III) use of corrosive water; (IV) fouling
or restriction of the water circuit by foreign material or like causes.
9. Damages resulting from operation with inadequate supply of air or water.
10. Damages resulting from use of components or accessories not approved by UPG (vent dampers, etc.).
11. Increase in fuel or electric cost.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABIL-
ITY AND FITNESS FOR A PARTICULAR PURPOSE.
SOME STATES DO NOT ALLOW THE DISCLAIMER OF IMPLIED WARRANTY, SO THAT THE ABOVE DISCLAIMER MAY NOT APPLY TO YOU.
SOME STATES ALLOW ONLY A PARTIAL LIMITATION ON IMPLIED WARRANTIES TO LIMIT THE DURATION OF IMPLIED WARRANTIES TO THE DURA-
TION OF THE EXPRESS WARRANTY. IN SUCH STATES, THE DURATION OF IMPLIED WARRANTIES IS HEREBY EXPRESSLY LIMITED TO THE DURA-
TION OF THE EXPRESS WARRANTY ON THE FACE HEREOF.
IN NO EVENT, WHETHER AS A RESULT OF BREACH OF WARRANTY OR CONTRACT, TORT (INCLUDING NEGLIGENCE) STRICT LIABILITY OR OTH-
ERWISE, SHALL UPG BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING BUT NOT LIMITED TO LOSS OF USE OF
THE EQUIPMENT OR ASSOCIATED EQUIPMENT, LOST REVENUES OR PROFITS, COST OF SUBSTITUTE EQUIPMENT OR COST OF FUEL OR ELEC-
TRICITY. THE ABOVE LIMITATIONS SHALL INURE TO THE BENEFIT OF UPG'S SUPPLIERS AND SUBCONTRACTORS. THE ABOVE LIMITATION ON
CONSEQUENTIAL DAMAGES SHALL NOT APPLY TO INJURIES TO PERSONS IN THE CASE OF CONSUMER GOODS.
SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, OR FOR STRICT
LIABILITY IN TORT, SO THAT THE ABOVE EXCLUSIONS AND LIMITATIONS MAY NOT APPLY TO YOU.
UPG DOES NOT ASSUME, OR AUTHORIZE ANY OTHER PERSON TO ASSUME FOR UPG, ANY OTHER LIABILITY FOR THE SALE OF THIS PRODUCT.
THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS. YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE.
For Owner's Information:
FURNACE TYPE HEAT EXCHANGER PARTSResidential Applications Non-Residential
Applications
Original Owner
90% P*DH / G9T-DH Lifetime 10 5
FG9-DH 15 10 1
PRODUCT MODEL. NO. ____________________ INSTALLATION DATE ______________________________
UNIT SERIAL NO. _________________________ INSTALLING DEALER ______________________________