BoilerFaultCodesThe 6 most common faults
01
Lack of burner ignition Engineer
no ignition signal from the full sequence ignition device
Full guide for Lack of burner ignition02
Safety thermostat lock out Engineer
Safety thermostat lock out
Full guide for Safety thermostat lock out03
Flue temperature probe NTC lock out Engineer
Flue temperature probe NTC lock out
Full guide for Flue temperature probe NTC lock out04
05
Lack of power supply Engineer
Lack of power supply or faulty electronic control p.c.b.
Full guide for Lack of power supply06
Excessive temperature on primary circuit Engineer
Excessive temperature on primary circuit
Full guide for Excessive temperature on primary circuitCall a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Biasi 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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