Carrier TJF004 LED Error Code Service Analysis, Heating Service Analysis, Symptom Cause Remedy

TROUBLESHOOTING

Table 32 — LED Error Code Service Analysis

SYMPTOM	CAUSE	REMEDY
Hardware failure.	Loss of power to control module (IGC).	Check 5 amp fuse on IGC, power to unit, 24-v circuit breaker, and transformer. Units
(LED OFF)		without a 24-v circuit breaker have an internal overload in the 24-v transformer. If the
		overload trips, allow 10 minutes for automatic reset.
Fan ON/OFF delay	High limit switch opens during heat	Ensure unit is fired on rate and temperature rise is correct.
modified (LED/FLASH)	exchanger warm-up period before fan-
	on delay expires.
	Limit switch opens within three minutes	Ensure units’ external static pressure is within application guidelines.
	after blower-off delay timing in Heating
	mode.
Limit switch fault.	High temperature limit switch is open.	Check the operation of the indoor (evaporator) fan motor.
(LED 2 flashes)		Ensure that the supply-air temperature rise is in accordance with
		the range on the unit nameplate.
Flame sense fault.	The IGC sensed flame that should not	Reset unit. If problem persists, replace control board.
(LED 3 flashes)	be present.
4 consecutive limit	Inadequate airflow to unit.	Check operation of indoor (evaporator) fan motor and that supply-air temperature rise
switch faults.		agrees with range on unit nameplate information.
(LED 4 flashes)
Ignition lockout.	Unit unsuccessfully attempted ignition	Check ignitor and flame sensor electrode spacing, gaps, etc. Ensure that flame sense
(LED 5 flashes)	for 15 minutes.	and ignition wires are properly terminated. Verify that unit is obtaining proper amount
		of gas.
Induced-draft motor	IGC does not sense that induced-draft	Check for proper voltage. If motor is operating, check the speed sensor plug/IGC Ter-
fault. (LED 6 flashes)	motor is operating.	minal J2 connection. Proper connection: PIN 1— White, PIN 2 — Red, PIN 3 — Black.
Rollout switch fault.	Rollout switch has opened.	Rollout switch will automatically reset, but IGC will continue to lock out unit. Check gas
(LED 7 flashes)		valve operation. Ensure that induced-draft blower wheel is properly secured to motor
		shaft. Reset unit at unit disconnect.
Internal control fault.	Microprocessor has sensed an error in	If error code is not cleared by resetting unit power, replace the IGC.
(LED 8 flashes)	the software or hardware.

If the IGC must be replaced, be sure to ground yourself to dissi- pate any electrical charge that may be present before handling new control board. The IGC is sensitive to static electricity and may be damaged if the necessary precautions are not taken.

IMPORTANT: Refer to Table 33 — Heating Service Analysis for additional troubleshooting analysis.

LEGEND

IGC — Integrated Gas Unit Controller

LED — Light-Emitting Diode

Table 33 — Heating Service Analysis

PROBLEM	CAUSE	REMEDY
Burners will not	Misaligned spark electrodes.	Check flame ignition and sensor electrode positioning.
ignite.		Adjust as needed.
	No gas at main burners.	Check gas line for air purge as necessary. After purging
		gas line of air, allow gas to dissipate for at least 5 minutes
		before attempting to relight unit.
		Check gas valve.
	Water in gas line.	Drain water and install drip leg to trap water.
	No power to furnace.	Check power supply, fuses, wiring, and circuit breaker.
	No 24 v power supply to control circuit.	Check transformer. Transformers with internal overcur-
		rent protection require a cool down period before resetting.
	Miswired or loose connections.	Check all wiring and wirenut connections.
	Burned-out heat anticipator in thermostat.	Replace thermostat.
	Broken thermostat wires.	Run continuity check. Replace wires, if necessary.
Inadequate heating.	Dirty air filter.	Clean or replace filter as necessary.
	Gas input to unit too low.	Check gas pressure at manifold. Clock gas meter for input. If too
		low, increase manifold pressure, or replace with correct orifices.
	Unit undersized for application.	Replace with proper unit or add additional unit.
	Restricted airflow.	Clean filter, replace filter, or remove any restrictions.
	Blower speed too low.	Use high speed tap, increase fan speed, or install
		optional blower, as suitable for individual units.
	Limit switch cycles main burners.	Check rotation of blower, thermostat heat anticipator settings,
		and temperature rise of unit. Adjust as needed.
	Too much outdoor air.	Adjust minimum position.
		Check economizer operation.
Poor flame	Incomplete combustion (lack of	Check all screws around flue outlets and burner
characteristics.	combustion air) results in:	compartment. Tighten as necessary.
	Aldehyde odors, CO, sooting flame, or floating flame.	Cracked heat exchanger.
		Overfired unit — reduce input, change orifices, or adjust
		gas line or manifold pressure.
		Check vent for restriction. Clean as necessary.
		Check orifice to burner alignment.
Burners will not	Unit is locked into Heating mode for a	Wait until mandatory one minute time period has
turn off.	one minute minimum.	elapsed or reset power to unit.

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