BoilerFaultCodesYour boiler has detected an internal computer or electrical fault that has caused it to stop working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Appliance fault (other than ignition lockout)
What causes this fault?
This fault occurs when the boiler's internal computer experiences a breakdown in communication or a critical component fails to report back to the main system. The most common reason is an electrical short or a failed component on the printed circuit board, which forces the boiler to shut down to prevent any further damage. Essentially, the 'brain' of the boiler has detected an internal logic error that it cannot resolve on its own.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Central heating demand indicator FLASHING FAST (five times per second) — no call-out fees, no surprises.
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