BoilerFaultCodesYour boiler’s internal computer has encountered a communication error or an internal glitch and cannot operate until it is reset or repaired.
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 main control board suffers a critical communication failure or an internal electronic crash. It is often caused by a sudden power surge, moisture getting onto the circuitry, or simply a hardware component reaching the end of its functional life. Because the central processor can no longer send or receive signals correctly, the system enters a fail-safe mode.
DIY fix possible
Locate the 'Reset' button on the boiler control panelPress and hold the button for 3 to 5 secondsWait for the boiler to restart and monitor if the code clears
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A boiler cover plan would cover faults like 252 — 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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