BoilerFaultCodesYour boiler's main internal pump is not speaking correctly to the control board, preventing the system from circulating heat.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Incorrectpumpdetected: Unsuitablepumpconnected,PWMplugnotpluggedinorhascome loose,multipleplugonthePCBnotpluggedincorrectly,interruptionin cableharness,electronicsdefective
What causes this fault?
This fault occurs when the boiler's brain loses communication with the internal pump that pushes hot water around your radiators. It is usually caused by a loose electrical connection, a damaged wiring harness, or the pump itself failing to send the correct signal back to the control board. Without this two-way communication, the boiler shuts down as a safety precaution to prevent overheating.
This fault is more common in autumn when heating systems are turned on for the first time after summer, as pump components can seize or electrical contacts can fail during long periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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