BoilerFaultCodesYour boiler's internal pump is not moving water around the system correctly, which has caused the boiler to stop working to prevent overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump fault
What causes this fault?
This fault occurs when the boiler's internal pump fails to circulate water, leading to a build-up of heat that triggers a safety shutdown. The most common reasons are a mechanical failure of the pump motor, a build-up of sludge or debris blocking the internal components, or a communication issue between the pump and the main control board.
This fault is more frequent in autumn or early winter when pumps that have been idle over the summer become 'stuck' or seized when the heating is first switched back on.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.89 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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