BoilerFaultCodesYour boiler has detected that the internal pump is not moving water around the system correctly, preventing it from heating your home.
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 computer detects that the circulation pump is failing to move water through the heat exchanger. The most common reason is that the pump has seized due to a buildup of debris or sludge, or the electrical connection between the pump and the main control board has failed.
This issue is most common during the first cold snap of autumn when a pump that has sat idle all summer is suddenly asked to work and fails to spin up.
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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