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6- 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.
7-
Evaluate the heat exchanger and combustion
chamber integrity by inspecting the heat exchanger
per the AHRI heat exchanger inspection procedure.
This can be viewed at www.ahrinet.org. See “Induced-
draft Furnace Heat Exchanger Inspection Procedure.
8- Ensure sufficient combustion air is available to the
furnace. Fresh air grilles and louvers (on unit and
in the room where the furnace is installed) must be
properly sized, open and unobstructed to provide
combustion air.
9- 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. If applicable, inspect and clean
air intake screen. Inspect the furnace return air duct
connection to ensure the duct is sealed to the furnace.
10- 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- Check the condition of the furnace cabinet insulation
and repair if necessary.
12- Perform a complete combustion analysis during the
furnace inspection to ensure proper combustion
and operation. Consult Service Literature for proper
combustion values.
13-
Verify operation of smoke detectors and 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-
off operation.
1 - Check the operation of the ignition system, inspect
and clean flame sensor. Check microamps before
and after. Check controls and safety devices (gas
valve, flame sensor, temperature limits). Consult
Service Manual for proper operating range. Thermal
Limits should be checked by restricting airflow and
not disconnecting the indoor blower. For additional
details, please see Service and Application Note
H049.
2 - Verify that system total static pressure and airflow
settings are within specific operating parameters.
3 - Clock gas meter to ensure that the unit is operating
at the specified firing rate. Check the supply
pressure and the manifold pressure.
If manifold
pressure adjustment is necessary, consult the
Service Literature for unit specific information
on adjusting gas pressure. Not all gas valves are
adjustable
. Verify correct temperature rise.
Winterizing and Condensate Trap Care
1 - Turn off 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
clean out cap.
