Lennox LGM156U Error Codes

Packaged HVAC · Packaged Unit

Model numbers in this family: LGM156U, LGM180U, LGM210U, LGM240U, LGM300U

• 1 Flash Rollout Switch open
• 2 Flashes Limit Switch open or opened multiple times during one heating demand
• 3 Flashes Pressure Switch open with CAI ON
• 4 Flashes Control lockout - failed to detect or sustain flame
• 5 Flashes Flame sensed and gas valve not energize
• 6 Flashes Pressure Switch closed with CAI OFF
• 7 Flashes Not used
• 8 Flashes Pressure switch opened repeatedly during heating demand
• Fast Flash Normal Operation - call for heat
• Slow Flash Normal Operation - No call for heat
• Steady Off Internal control board fault or no power
• Steady On Control board failure

Reference only. Confirm against the manual for your exact model. Data release 105f66ecb9e96e5dc473025d.