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6-  Check the cleanliness of blower assembly and 
clean the housing, blower wheel and blower motor if 
necessary .
7-  Inspect the condensate drain and trap for leaks and 
cracks. The drain and trap must also be cleaned 
and the trap must be primed with water. Inspect the 
rubber hoses connected to the pressure switches for 
cracks or loose connections, replace as necessary. 
Remove the rubber hoses from the cold end header 
box and inspect for any blockage, clean as needed. 
If strainers are installed in the hoses remember to 
remove and clean before reinstalling the hoses.
8-  Evaluate the heat exchanger integrity by inspecting 
the heat exchanger per the AHRI heat exchanger 
inspection procedure. This procedure can be viewed 
at www.ahrinet.org
9-  Ensure  sucient  combustion  air  is  available  to  the 
furnace. Fresh air grilles and louvers (on the unit and 
in the room where the furnace is installed) must be 
properly sized, open and unobstructed to provide 
combustion air.
10-  Inspect the furnace intake and exhaust pipes to make 
sure they are in place, structurally sound, without 
holes, blockage or leakage and the exhaust pipe 
is sloped toward the furnace. Inspect terminations 
to ensure they are free of obstructions and are 
structurally sound. Inspect the furnace return air 
duct connection to ensure the duct is sealed to the 
furnace. Check for air leaks on supply and return 
ducts and seal where necessary.
11-  Inspect the furnace return air duct connection to 
ensure the duct is sealed to the furnace. Check for 
air leaks on supply and return ducts and seal where 
necessary.
12-  Check the condition of the furnace cabinet insulation 
and repair if necessary.
13-  Perform a complete combustion analysis during the 
furnace inspection to ensure proper combustion 
and operation. Consult Service Literature for proper 
combustion values.
14-  Verify operation of CO detectors and replace 
batteries as required.
Perform a general system test. Turn on the furnace to 
check operating functions such as the start-up and shut-
o operation.
1 -   Check the operation of the ignition system, inspect 
and  clean ame sensor.  Check microamps before 
and after. Check controls and safety devices (gas 
valve,  ame  sensor,  temperature  limits).  Consult 
Service Manual for proper operating range. Thermal 
Limits should be checked by restricting airow and 
not disconnecting the indoor blower. For additional 
details, please see Service and Application Note 
H049.
2 -  Verify  that  system  total  static  pressure  and  airow 
settings are within specic operating parameters.
3 -  Clock gas meter to ensure that the unit is operating at 
the specied ring rate for each stage of operation.
Check the supply pressure and the manifold pressure 
on  both  low  re and high  re.  If  manifold  pressure 
adjustment is necessary, consult the Service 
Literature  for  unit  specic  information  on  adjusting 
gas pressure. Not all gas valves are adjustable. 
Verify correct temperature rise.
Winterizing and Condensate Trap Care
1 -   Turn o power to the furnace.
2 -  Have a shallow pan ready to empty condensate 
water.
3 -  Remove the clean out cap from the condensate trap 
and empty water. Inspect the trap then reinstall the 
drain plug.
Cleaning the Burner Assembly (if needed)
1 -   Turn o electrical and gas power supplies to furnace. 
Remove upper and lower furnace access panels.
2 -  Disconnect the 2-pin plug from the gas valve.
3 -  Remove the burner box cover (if equipped).
4 -  Disconnect the gas supply line from the gas valve. 
Remove gas valve/manifold assembly.
5 -  Loosen clamps and remove combustion air intake 
exible connector (if equipped).
6 -  Mark and disconnect sensor wire from the sensor. 
Disconnect plug from the ignitor at the burner box.
7 -  Remove four screws which secure burner box 
assembly to vest panel. Remove burner box from 
the unit.
8 -  Use the soft brush attachment on a vacuum cleaner 
to gently clean the face of the burners. Visually 
inspect the inside of the burners and crossovers for 
any blockage caused by foreign matter. Remove any 
blockage.
9 -  Reinstall the burner box assembly using the existing 
four screws. Make sure that the burners line up in the 
center of the burner ports.
11 -  Reconnect the sensor wire and reconnect the 2-pin 
plug to the ignitor wiring harness.
11 -  Reinstall combustion air intake exible connector (if 
equipped), secure using existing clamps.
12 -  Reinstall the gas valve manifold assembly. 
Reconnect the gas supply line to the gas valve. 
Reinstall the burner box cover.
13 -  Reconnect plug to gas valve.
14 -  Replace the blower compartment access panel.
15 -  Refer to instruction on verifying gas and electrical 
connections when re-establishing supplies.
16 -  Follow lighting instructions to light and operate 
furnace for 5 minutes to ensure that heat exchanger 
is clean and dry and that furnace is operating 
properly.
17 -  Replace access panel.