Model reference
Lennox G23Q2/3(X)-75
Furnace
1 document16 error codes
Available documentation
Service Manual
- G23(X) Series Service Literature52 pg
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Error codes (16)
CodeMeaning
LED OffControl failure, power failure, or hard lockout on G776 ignition control.LED Slow FlashControl retry periodLED Steady OnNormal operation of the G776 ignition control.LED1 Alternating Fast Flash / LED2 Alternating Fast FlashImproper main ground or line voltage below 75 volts; OR broken ignitor; OR open…LED1 Alternating Slow Flash / LED2 Alternating Slow FlashWatchguardLED1 Fast Flash / LED2 Fast Flash (Simultaneous)Normal operationLED1 Fast Flash / LED2 Slow FlashMain power polarity reversedLED1 Off / LED2 OnCircuit board failure or control wired incorrectly.LED1 Off / LED2 Slow FlashPressure switch open or has opened 5 times during a single call for heat; OR…LED1 On / LED2 OffCircuit board failure or control wired incorrectly.LED1 On / LED2 OnCircuit board failure or control wired incorrectly.LED1 On / LED2 Slow FlashRollout switch open OR 9-pin connector improperly attached.LED1 Slow Flash / LED2 Fast FlashLow flame signalLED1 Slow Flash / LED2 OffFlame sensed without gas valve energized.LED1 Slow Flash / LED2 OnPrimary or secondary limit openLED1 Slow Flash / LED2 Slow Flash (Simultaneous)Power onRelated Lennox furnace models
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