BoilerFaultCodesYour boiler's internal computer has encountered a software or electronic error and can no longer control the heating properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal error.
What causes this fault?
This fault occurs when the boiler's main control board experiences a persistent data error or a physical failure in its electronic circuitry. It is essentially a communication breakdown between the boiler's Brain and its components, often caused by age-related degradation of the circuit board or a sudden electrical surge.
This fault can sometimes follow heavy summer storms, as power surges or nearby lightning strikes are known to damage sensitive electronic control boards.
DIY fix possible
Press the 'Reset' button on the front of the boiler once.If it does not reset, turn the power supply to the boiler off at the fused spur switch.Wait 60 seconds and then turn the power back on.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F0 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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