Check the burner flames for good adjustment, a stable, soft and
blue flame that is not curling, floating or lifting off.
Flue pipe system. Check for blockage and/or leakage. Check
the outside termination and the connections at and internal to
Combustion air intake pipe system (where applicable). Check
for blockage and/or leakage. Check the outside termination
and the connection at the furnace.
Heat exchanger. Check for corrosion and/or buildup within
the heat exchanger passageways.
Burners. Check for proper ignition, burner flame and flame
sense. Flames should extend directly outward from burners
without curling, floating or lifting off.
Wiring. Check electrical connections for tightness and/or
corrosion. Check wires for damage.
Filters. Check that the filters are clean and in the proper
placement in the furnace or duct system.
To avoid property damage, personal injury or death,
disconnect electrical power before removing filters. Never
operate furnace without a filter installed because dust
and lint will build up on internal parts resulting in loss of
efficiency, equipment damage and possible fire.
A return air filter is not supplied with this furnace and cannot be
installed inside the cabinet; however, a means of filtering all of the
return air (intake) must be provided. Your installer will supply
filters at the time of installation. Become familiar with filter
location and procedures for removing, cleaning and replacing
If you need assistance, contact the installer of your furnace or
another qualified servicer.
Filters must be inspected, cleaned or changed every 2 months or
as required. As a homeowner, it is your personal responsibility to
keep air filters clean. Remember that dirty filters are the most
common cause of inadequate heating or cooling performance.
Filters can be located in a central return grille or a side-panel
external filter rack. To remove filters from an external filter rack,
follow the directions provided with the external filter rack kit. To
remove all other filter configurations, consult with the installing
contractor. If you are using a media or electronic air cleaner,
follow the directions provided with the air cleaner for proper filter
removal, cleaning and replacement.
Filter Cleaning and/or Replacement
Disposable filters must be replaced with a filter or filters of the
same size as that which is removed. Filters must comply with
UL900 or CAN/ULC-S111 Standards.
Permanent filters must be cleaned, washed and dried as
specified by the filter manufacturer. If it becomes necessary to
replace a permanent filter, it must be replaced with a filter or
filters of the same size as that which is removed. Filters must
comply with UL900 or CAN/ULC-S111 Standards.
When reinstalling filters, be careful to maintain correct airflow
If your furnace is not operating or is performing improperly, take
time to perform the following checks before requesting service. A
couple of simple checks may allow you to avoid a service call. If
the following steps do not resolve the problem, contact a
qualified servicer for further troubleshooting and/or repairs. Do
not attempt troubleshooting beyond that which is outlined below.
Do not attempt repairs yourself.
Check the blower compartment sight glass. If LED is flashing,
record the number of flashes seen in sequence, shut down
your unit as outlined in the "Furnace Shutdown" section, and
contact a qualified servicer for further troubleshooting and/or
repairs. Refer to the Installation Instructions for code
identification. If the LED is not flashing, continue with checks.
Check the thermostat for proper operation. Verify that it is set
on HEAT and that the temperature setting (above room
temperature) is appropriate.
Check the fuse or circuit breaker in the furnace electrical
circuit. Replace if necessary.
Check to see that the manual gas shutoff valve external to the
furnace is in the ON position. If the valve is in the OFF
position, turn the gas ON following the start-up procedures
outlined in the "Furnace Start-Up" section.
Check for dirty filter(s). This is the most common cause of
improper furnace operation. Replace or clean filters as
Check for blocked return air or supply air grilles throughout
your home. Grilles may be blocked by furniture, drapery,
clothes, carpeting, etc. Clear any blockage.