BoilerFaultCodesYour boiler has detected that the water pump is likely stuck or not moving water correctly, which means the system cannot heat up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: N/A
What causes this fault?
This fault occurs when the boiler's control system detects that the internal pump is not rotating or circulating water effectively. The most common reason is that debris or magnetite from the heating system has jammed the pump's internal components, though it can also be caused by a mechanical failure of the motor or a communication error starting from the control board.
This issue is frequently seen at the start of autumn when heating is turned back on after being idle all summer, as stagnant debris is more likely to settle and seize the pump.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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