ABNORMAL OPERATION - HEATING
INTERNAL CONTROL FAILURE
If the integrated ignition control in this unit encounters an internal fault, it will go into a “hard” lockout and turn off the diagnostic LED. If diagnostic LED indicates an internal fault, check power supply to unit for proper voltage, check all fuses, circuit breakers and wiring. Disconnect electric power for five seconds. If LED remains off after restoring power, replace control.
EXTERNAL LOCKOUT
An external lockout occurs if the integrated ignition control determines that a measurable combustion cannot be established within three (3) consecutive ignition attempts. If flame is not established within the seven (7) second trial for ignition, the gas valve is de-energized, 30 second inter-purge cycle is completed, and ignition is re-attempted. The control will repeat this routine three times if a measurable combustion is not established. The control will then shut off the induced draft blower and go into a lockout state.
If flame is established but lost, the control will energize the circulator blower at the heat speed and then begin a new ignition sequence. If flame is established then lost on subsequent attempts, the control will recycle the ignition sequence.
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 thermostat 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.
•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, 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 diagnostic LED (red) code is two (2) flashes.
PRESSURE SWITCH STUCK CLOSED
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 red LED code for this fault is three (3) flashes.
OPEN THERMAL PROTECTION DEVICE
If a limit switch opens, the gas valve is immediately de- energized, the induced draft and air circulating blowers are energized. 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.
PRIMARY LIMIT
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.
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.
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 diagnostic fault code is five (5) flashes (red LED) for this condition. The flame diagnostic LED (amber) will flash (2) times to indicate 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.
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 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 or thermostat call for cooling is restored. (Compressor is off a total of three minutes). The diagnostic red LED will flash six (6) times to indicate the compressor contactor output is being delayed.
