BoilerFaultCodesYour boiler's main internal computer has developed a memory or communication error and can no longer control the heating system 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 occurring means the boiler’s internal computer has suffered a serious electronic failure and can no longer process data correctly. It is often caused by a physical component failure on the circuit board or loose wiring connections that disrupt the flow of information. Factors like age, heat stress over many years, or power surges are the most likely reasons the board has stopped working.
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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