| Pattern | Meaning | Severity |
|---|---|---|
| 0 flashes | high | |
| 1 flash | critical | |
| 1 flash | info | |
| 2 flashes | high | |
| 3 flashes | high | |
| 4 flashes | high | |
| 5 flashes | critical | |
| 6 flashes | medium | |
| 7 flashes | high |
| Code | Description | Severity |
|---|---|---|
| 1 Flash | Lockout due to Ignition Failure | critical |
| 1 flash | Low Heat | info |
| 2 Flash | Pressure Switch Stuck Open | high |
| 2 flash | High Heat | info |
| 3 Flash | Pressure Switch Stuck Closed | high |
| 3 flash | Pressure Switch Open | critical |
| 4 Flash | Open Limit Switch | high |
| 4 flash | Limit Circuit Open | critical |
| 5 Flash | Flame Sensed Without Call for Heat | critical |
| 5 flash | Flame Sensed Out of Sequence | critical |
| 6 Flash | Line Voltage Polarity Reversed | medium |
| 6 flash | Ignition Lockout | critical |
| 7 Flash | Gas Valve Circuit Failure | high |
| 7 flash | Rollout Switch Open | emergency |
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