BoilerFaultCodesYour boiler is failing to circulate water for your radiators, meaning your heating will not warm up despite being turned on.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump does not run when central heating demand is active
What causes this fault?
This fault occurs when the boiler's internal computer tries to send power to the pump but detects no movement or electrical response. The most common reason is that the pump has seized due to a build-up of debris in the system water or the internal motor has reached the end of its lifespan. In some cases, a loose connection or a fault on the main control board prevents the electrical signal from reaching the pump at all.
This fault is frequently seen at the start of autumn when the heating is turned on for the first time after being idle all summer, as pumps are prone to seizing 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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