| Pattern | Meaning | Severity |
|---|---|---|
| 1 flash | info | |
| 2 flashes | critical | |
| 3 flashes | high | |
| 4 flashes | high | |
| 5 flashes | critical | |
| 6 flashes | medium | |
| 7 flashes | high | |
| 8 flashes | high |
| Code | Description | Severity |
|---|---|---|
| 201 | Limit Switch Open | critical |
| 227 | No Flame Sensed | critical |
| 270 | High Pressure Switch Open | critical |
| 271 | Low Pressure Switch Open | critical |
| 292 | Compressor Lockout | critical |
| E201 | Control Self-Diagnostics Failure | high |
| E225 | Roll-Out Switch Open | critical |
| E227 | External Low Voltage Short | medium |
| E228 | Blocked Vent/Pressure Switch | high |
| E250 | Ignition Failure / No Flame Detected | critical |
| E269 | Limit Switch Circuit Lockout | critical |
| E270 | High Limit Switch Open | high |
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