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• Check rollout limit
If the burner flames are not properly drawn into the heat
exchanger, the flame rollout protection device will open.
Possible causes are restricted or blocked flue passages,
blocked or cracked heat exchanger, a failed induced
draft blower, or insufficient combustion air. The rollout
protection device is a manual reset limit located on the
burner bracket. The cause of the flame rollout must be
determined and corrected before resetting the limit.
• Check flame sensor
A drop in flame signal can be caused by nearly invisible
coating on the sensor. Remove the sensor and carefully
clean with steel wool.
• Check wiring
Check wiring for opens/shorts and miswiring.
IMPORTANT: If you have to frequently reset your
gas/electric package unit, it means that a problem
exists that should be corrected. Contact a
qualified servicer for further information.
Pressure Switch Stuck Open (2 FLASH CODE)
IA pressure switch stuck open can be caused by a faulty
pressure switch, faulty wiring, a disconnected or damaged
hose, a blocked or restricted flue, or a faulty induced draft
blower. If the control senses an open pressure switch
during the pre-purge cycle, the induced draft blower only
will be energized.
If the pressure switch opens after ignition has begun the
gas valve is deenergized, the circulator blower heat off
cycle begins, and the induced draft blower remains on.
The diagnostic fault code is two flashes.
Pressure Switch Stuck Closed (3 FLASH CODE)
A stuck closed pressure switch can be caused by a faulty
pressure switch or faulty wiring. If the control encounters
a pressure switch stuck closed, the induced draft blower
remains off. The diagnostic LED code for this fault is three
(3) flashes.
Open Thermal Protection Device (4 FLASH CODE)
If the primary limit switch opens, the gas valve is
immediately deenergized, the induced draft and air
circulating blowers are energized. The induced draft and
air circulator blowers remain energized until the limit switch
recloses. The diagnostic fault code for an open limit is four
(4) flashes.
A primary limit will open due to excessive supply air
temperatures. This can be caused by a dirty filter,
excessive duct static, insufficient air flow, or a faulty limit.
Check filters, total external duct static, blower motor,
blower motor speed tap (see wiring diagram), and limit.
This limit will automatically reset once the temperature falls
below a preset level.
Flame Detected with Gas Valve Closed
(5 FLASH CODE)
If flame is detected with the gas valve deenergized, the
combustion and air circulator blowers are energized. The
diagnostic fault code is five (5) flashes for this condition.
The control can be reset by removing the power supply
to the unit or it will automatically reset after one hour.
Miswiring is the probable cause for this fault.
Abnormal Operation - Cooling Codes
Short Cycle Compressor Delay (6 FLASH CODE)
The automatic ignition control has a built-in feature that
prevents damage to the compressor in short cycling
situations. In the event of intermittent power losses or
intermittent thermostat operation, the ignition control will
delay output to the compressor contactor for three minutes
from the time power is restored. (Compressor is off a total
of three minutes). The diagnostic LED will flash six (6)
times to indicate the compressor contactor output is being
delayed.
NOTE: Some electronic thermostats also have a
built-in compressor short cycle timer that may be
longer than the three minute delay given above.
If you are using an electronic thermostat and the
compressor has not started after three minutes,
wait an additional five minutes to allow the
thermostat to complete its short cycle delay time.
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