Model reference

Lennox G50DF-24A-070

Furnace

1 document12 error codes

Available documentation

Service Manual

G50DF(X) Service Literature32 pg
Covers this model

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LED1 ALT FAST FLASH / LED2 ALT FAST FLASH on my Lennox G50DF-24A-070

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During ignitor warm-up: improper main

From Service Manual 921548, p.40:

1.Access service mode to confirm the active fault code and read stored error history.

2.Measure control board supply voltage at test points. Expected: 12 VDC and 5 VDC.

3.Inspect all connectors on the main control for corrosion or backed-out pins.

Part WPW10804018

Electronic control board

Error codes (12)

CodeMeaning

LED1 ALT FAST FLASH / LED2 ALT FAST FLASHDuring ignitor warm-up LED1 ALT SLOW FLASH / LED2 ALT SLOW FLASHWatchguard LED1 FAST FLASH / LED2 FAST FLASH (simultaneous)Normal operation signaled when heating demand initiated at thermostat.LED1 FAST FLASH / LED2 SLOW FLASHMain power polarity reversed; switch line and neutral; improper main ground.LED1 OFF / LED2 ONRollout switch open or low voltage pin connector improperly attached.LED1 OFF / LED2 SLOW FLASHProve switch open, or blocked inlet/exhaust vent, or prove switch closed prior…LED1 ON / LED2 OFFFlame sensed without gas valve energized.LED1 ON / LED2 ONCircuit board failure or control wired incorrectly.LED1 ON / LED2 SLOW FLASHFlame sensed without gas valve energized, or rollout switch open, or low…LED1 SLOW FLASH / LED2 FAST FLASHLow flame signal LED1 SLOW FLASH / LED2 ONPrimary or secondary limit switch open; limit must close within 3 minutes or…LED1 SLOW FLASH / LED2 SLOW FLASH (simultaneous)Power on, normal operation; also signaled during cooling and continuous fan.

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