BoilerFaultCodesYour boiler is simply cooling itself down naturally after the burner has switched off to move leftover heat into your radiators.
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: Main burner off, pump running to transfer remaining heat from boiler into the system
What causes this fault?
This code appears when the boiler has reached its target temperature and shuts off the burner while keeping the internal pump running. It is a natural part of the heating cycle designed to move leftover heat away from the heat exchanger and into your radiators to prevent the unit from overheating. The boiler has not stopped due to a failure, but is simply managing its internal temperature before the next cycle.
DIY fix possible
Wait for the pump to finish its overrun cycleEnsure your room thermostat or programmer is set to the desired temperatureCheck that at least one radiator valve is open to allow heat to circulate
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