| Pattern | Meaning | Severity |
|---|---|---|
| 1 flash | critical | |
| 2 flashes | high | |
| 3 flashes | high | |
| 4 flashes | high | |
| 5 flashes | critical | |
| 6 flashes | critical | |
| 7 flashes | critical |
| Code | Description | Severity |
|---|---|---|
| 1 | Heating Operational | info |
| 1 Flash | Flame Without Gas Valve Energized | critical |
| 2 | External Limit Fault | critical |
| 2 Flash | Pressure Switch Stuck Closed | high |
| 3 | Pressure Switch Fault | critical |
| 3 Flash | Pressure Switch Stuck Open | high |
| 4 | Flame Sense Fault | warning |
| 4 Flash | Open High Limit | high |
| 5 | Ignition Fault | critical |
| 5 Flash | Flame Rollout Switch Open | critical |
| 6 Flash | Ignition Failure | critical |
| 7 Flash | Ignition Lockout - Max Retries | critical |
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