19
The diagnostic fault code is 1 flash for a lockout due to failed
ignition attempts. The integrated control will automatically
reset after one hour, or it can be reset by removing the ther-
mostat signal or disconnecting the electrical power supply
for over five seconds. If the diagnostic red LED indicates an
external lockout, perform the following checks:
•
Check the supply and manifold pressures
•
Check the gas orifices for debris
•
Check gas valve for proper operation
•
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.
•
Auxiliary/Secondary Limit
A dirty filter, excessive duct static, insufficient air
flow, a faulty limit, or a failed circulator blower can
cause this limit to open. Check filters, total external
duct static, circulator blower motor, blower motor
speed tap (see wiring diagram), and limit. An
interruption in electrical power during a heating
cycle may also cause the auxiliary limit to open.
The automatic reset secondary limit is located on
top of the circulator blower assembly.
•
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 wiring
Check wiring for opens/shorts and miswiring.
IMPORTANT NOTE:
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
A pressure switch stuck open can be caused by a faulty
pressure switch, faulty wiring, a disconnected or damaged
hose, a blocked or restricted flue, a blocked pressure tap 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 de-energized, the circulator blower heat off cycle
begins, and the induced draft blower remains on. The diag-
nostic LED (red) code is two (2) flashes.
Pressure Switch Stuck Closed
A stuck closed pressure switch can be caused by a faulty pres-
sure switch or faulty wiring. If the control encounters a pressure
switch stuck closed, the induced draft blower remains off. The
diagnostic red LED code for this fault is three (3) flashes.
Primary Limit
A primary limit will open due to excessive supply air tem-
peratures. 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 automati-
cally reset once the temperature falls below a preset level.
If a limit switch opens, the gas valve is immediately de-en-
ergized, the induced draft and air circulating blowers are en-
ergized. The induced draft and air circulator blowers remain
energized until the limit switch re-closes. The diagnostic
LED (red) code for an open limit is four (4) flashes.
NOTE:
If the primary limit opens five (5) times within the
same call for heat, the ignition control will lock out for one
(1) hour with the air circulating blower energized at high heat
speed. The diagnostic LED (red) code for this condition is
seven (7) flashes.
Flame Detected with Gas Valve Closed
If flame is detected with the gas valve de-energized, the
combustion and air circulator blowers are energized. The di-
agnostic fault code is five (5) flashes (red LED) for this con
-
dition. The flame diagnostic LED (amber) will flash (2) times
to indicate this condition. The control can be reset by remov-
ing the power supply to the unit or it will automatically reset
after one hour. Miswiring is the probable cause for this fault.
Low Flame Signal
Under some conditions, the fuel or air supply can create a
nearly invisible coating on the flame sensor. This coating
acts as an insulator causing a drop in the flame signal. If the
flame signal drops below a predetermined value, the ignition
control will display an error code of (1) flash on the amber
diagnostic LED. The unit will continue to operate until the
control can no longer detect flame.
Abnormal Operation - Cooling
Short Cycle Compressor Delay
The automatic ignition control has a built-in feature that pre-
vents damage to the compressor in short cycling situations.
In the event of intermittent power losses or intermittent ther-
mostat operation, the ignition control will delay output to the
compressor contactor for three minutes from the time power
is restored or thermostat call for cooling is restored. (Com-
pressor is off a total of three minutes). The diagnostic red
LED will flash six (6) times to indicate the compressor con
-
tactor 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 elec-
tronic 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.
High Pressure Switch/Loss of Charge Switch
Some models include a high pressure cutout switch and/
or a loss of charge cutout switch. The high pressure cutout
switch protects the refrigeration system from excessive op-
erating pressures. The loss of charge cutout switch protects
