What It Means
- Control lockout - failed to detect or sustain flame
- Ignition lockout from too many flame losses within single call for heat.
Lennox Packaged Unit
Lennox Packaged Unit Error Code 4 Flashes
Packaged Unit
4 Flashes means different things on different Packaged Unit models. Enter your model number to see only your reading, or find your model below.
Causes & actions from Lennox
Control lockout - failed to detect or sustain flame
10 models
LDT078, LDT092, LDT102, LDT120, LDT152, LGM156U, LGM180U, LGM210U, LGM240U, LGM300U
Packaged HVAC (outdoor)
How it shows
- dsi ignition heartbeat led: 4 Flashes
This manual entry does not list further causes or actions.
Applicable models & manual sources
- LDT078
Control lockout – failed to detect or sustain flame
LDT078, LDT092, LDT102, LDT120, LDT152
- LGM156U
Control lockout – failed to detect or sustain flame
LGM156U, LGM180U, LGM210U, LGM240U, LGM300U
Ignition lockout from too many flame losses within single call for heat.
8 models
LGM036, LGM048, LGM060, LGM074, LGT036, LGT048, LGT060, LGT072
Packaged HVAC (indoor)
How it shows
- dsi ignition heartbeat led: 4 Flashes
This manual entry does not list further causes or actions.
Applicable models & manual sources
- LGM036
Ignition lockout from too many flame losses within single call for heat.
LGM036, LGM048, LGM060, LGM074
- LGT036
Ignition lockout from too many flame losses within single call for heat.
LGT036, LGT048, LGT060, LGT072
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
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