BoilerFaultCodesYour boiler's main control board has encountered an internal electronic error, meaning the 'brain' of the system can no longer manage the heating and hot water safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main PCB fault.
What causes this fault?
This fault occurs when the boiler's internal computer experiences a critical electronic failure or a 'brain freeze' that prevents it from processing commands. It is typically caused by a short circuit on the control board, aged components failing over time, or a communication error between the board and the wiring harness.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F13 — no call-out fees, no surprises.
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