BoilerFaultCodesWhat the manual says
Manufacturer manualDHW mode: Pump overrun. The pump overrun for domestic hot water mode is activated.
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This occurs when you finish using a hot tap and the boiler needs to dissipate the high levels of residual heat left inside the heat exchanger. The internal pump continues to run for a short period to move this hot water away, preventing the internal components from overheating or becoming damaged by trapped heat. It is a normal safety function rather than a failure of any specific part.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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