The 6 most common faults
01
1 flash green Engineer
Temperature protection: Maximum flow temperature exceeded, Flow temperature rise rate too high, Excessive difference between flow and return temperature
Full guide for 1 flash green02
2 flashes green Engineer
Shutdown input: BL terminals on User Interaction Controller are open
Full guide for 2 flashes green03
3 flashes green Engineer
Flame loss: No flame detected during operation
Full guide for 3 flashes green04
4 flashes green Engineer
Communication fault: Bad connection or wiring fault, Internal communication fault
Full guide for 4 flashes green05
5 flashes green Engineer
Parameter fault: Parameter error or faulty PU, Configuration error or PCB fault
Full guide for 5 flashes green06
6 flashes green Engineer
Miscellaneous: Internal fault in combustion control unit
Full guide for 6 flashes greenCall a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Baxi shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue
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