White Rodgers 50M56-7433 installation instructions Troubleshooting, Homeowner Help Line

TROUBLESHOOTING

Red LED
Flash	Error/Condition	Comments/Troubleshooting
1	External lockout	Failure to sense flame is often caused by carbon deposits on the flame
	(exceeded retries)	sensor, a disconnected or shorted flame sensor lead or a poorly grounded
		furnace. Carbon deposits can be cleaned with emery cloth. Verify sensor is
		not contacting the burner and is located in a good position to sense flame.
		Ignitor must be positioned to light the gas immediately when the valve
		opens. If the ignitor has been replaced, verify hot spot position has not
		changed.
		Check sensor lead for shorting and verify furnace is grounded properly.
		Verify gas supply to valve, gas valve in "On" position and appliance
		lighting properly. Verify flame reaches flame sensor during ignition
		attempts and gas pressures are correct.
2	Pressure switch stuck	Pressure switch stuck closed. Check switch function, verify inducer is
	closed	turning off. Refer to wiring diagram, terminals PSI / PSO.
3	Pressure switch stuck	Check pressure switch function and tubing. Verify inducer is turning on
	open	and pulling sufficient vacuum to engage switch. Refer to wiring diagram,
		terminals PSI / PSO.
4	Open high temperature	Verify continuity through limit switch circuit. Refer to wiring diagram
	limit switch	terminals, HLI / HLO.
5	Flame sensed with gas	Verify the gas valve is operating and shutting down properly. Flame in
	valve	burner assembly should extinguish promptly at the end of the cycle. Check
	de-energized	orifices and gas pressure.
6	Open rollout switch	Verify continuity through rollout switch circuit. Refer to wiring diagram
		terminals, RO IN / RO OUT.
7	Low flame sense current	Low flame sense current is often caused by carbon deposits on the flame
		sensor, a poorly grounded furnace or a mis-aligned flame sense probe.
		Carbon deposits can be cleaned with emery cloth.
		Check or improve furnace and module ground. Verify sensor is located in
		or very near flame as specified by the appliance manufacturer. Refer to
		wiring diagram FS terminal and GND.
8	Ignitor relay fault	This flash code does not indicate a broken, disconnected or shorted
		ignitor. It indicates the ignitor relay contacts on the ignition module are not
		functioning properly. Replace the ignition module.
Rapid Flash	Reversed polarity	Verify the control and furnace are properly grounded. Check and reverse
		polarity (primary or secondary) if incorrect.
Continuous On	Normal operation	No fault
Off	Control failure	Verify power to the control, replace control if power is at the control and no
		lit Red LED

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