23
The diagnostic fault code is 1 flash for a lockout due to failed
ignition attempts or flame dropouts. The integrated control will
automatically reset after one hour, or it can be reset by removing
the thermostat signal or disconnecting the electrical power supply
for over five seconds. If the diagnostic 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 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.
•
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)
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, 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 pres-
sure switch opens after ignition has begun the gas valve is deener-
gized, 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 combus-
tion 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.
T
O
PREVENT
UNRELIABLE
OPERATION
OR
EQUIPMENT
DAMAGE
,
THE
GAS
MANIFOLD
PRESSURE
MUST
BE
AS
SPECIFIED
ON
THE
UNIT
RATING
PLATE
. O
NLY
MINOR
ADJUSTMENTS
SHOULD
BE
MADE
BY
ADJUSTING
THE
GAS
VALVE
PRESSURE
REGULATOR
.
CAUTION