BoilerFaultCodesYour boiler has experienced a communication error that has stopped it from working, and it requires a manual power reset to clear the internal memory.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Remote reset supervision, switch off the power at the mains – if problem repeats Contact a heating engineer
What causes this fault?
This fault occurs when the boiler's internal computer loses track of its safety checks and needs to clear its temporary memory. The most common reason is a brief disruption in communication between the main control board and the display, or an electrical glitch that causes the software to stall. If a power reset doesn't work, it usually indicates that the wiring has come loose or the electronic circuit board is failing.
DIY fix possible
Locate the fused spur switch or main power switch for the boilerTurn the power 'Off' and wait for at least 30 secondsTurn the power back 'On' and wait for the boiler to restart
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like U4-67 — 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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