BoilerFaultCodesYour boiler has encountered an internal communication error between its main electronic control boards, meaning it cannot currently function or heat your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's two main 'brains'—the primary control board and the display board—stop talking to each other. It is usually caused by a loose internal connection, a glitch in the software, or a component failure on one of the electronic circuit boards. Think of it like a computer crashing because two internal parts can no longer share information.
DIY fix possible
Locate the power switch or fused spur for the boilerTurn the power off, wait for 30 seconds, and turn it back onPress the 'Reset' button on the boiler display once it restarts
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A boiler cover plan would cover faults like 363 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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