BoilerFaultCodesYour boiler is performing a routine safety self-check and will restart automatically in a few minutes.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: The boiler was switched off for a maximum of 2 minutes because it had been operating continuously for more than 24 hours
What causes this fault?
This occurs because the boiler is programmed to perform a safety self-test after running for twenty-four hours straight without a break. To complete this check, the system briefly pauses the burner to ensure all internal safety sensors are functioning correctly. It is a built-in software feature rather than a mechanical failure or a broken part.
This code is more common during the winter months when the heating is left on constantly to combat freezing external temperatures.
DIY fix possible
Wait for 2 minutes for the boiler to complete its safety cycleMonitor the display to ensure the code clears and the boiler restarts automaticallyIf the code persists for more than 10 minutes, try a manual reset
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A boiler cover plan would cover faults like C4273 — no call-out fees, no surprises.
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