Model reference
Lennox GCS26-036-100
HVAC
1 document7 error codes2 service modes
Available documentation
Service Manual
- GCS/CHP26 Service Literature24 pg
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Error codes (7)
CodeMeaning
2 FlashesLockout3 FlashesPressure switch open or closed (stuck).4 FlashesHigh limit or rollout switch open.5 FlashesFlame sensed and gas valve not energized.Fast FlashNormal operation, call for heat.Slow FlashNormal operation, no call for heat.Steady FlashCircuit board self-check failure or ignition/blower control wired incorrectly.Service modes (2)
- Defrost Control Test Mode["Ensure defrost sensor will be closed at 32°F (0°C) or below; if temperatures are too high, jumper…
- GCI-2 Diagnostic LED Mode["Observe the green diagnostic LED on the GCI-2 control board during operation.","LED flash…
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