BoilerFaultCodesYour boiler has stopped working because it cannot detect any water being moved through the system by the internal pump.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump test failed
What causes this fault?
This fault occurs when the boiler's control system attempts to start the internal pump but fails to detect the expected change in water pressure or flow. The most common reason is that the pump has become seized or electrically faulty, though it can also be caused by a blockage in the heat exchanger or a failing sensor that is unable to report that water is moving correctly.
This issue often develops at the start of autumn when a pump that has been idle all summer becomes stuck due to a buildup of internal debris.
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 CE266 — no call-out fees, no surprises.
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