Model reference
Lennox GCS29
HVAC
2 documents7 error codes1 service mode
Available documentation
Service Manual
- Lennox GCS29 Manual4 pg
- GCS/CHA/CHP Service Literature32 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 (1)
- Defrost system test (CHP29)["Ensure defrost sensor closes at 32°F or below; if temperatures are above 32°F, jumper between…
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