BoilerFaultCodesYour boiler is struggling to pump water around your home correctly because it cannot find the right speed setting for your heating system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Pump map (heating - combi & system only)
What causes this fault?
This fault occurs when the boiler's control board loses communication with the internal pump or cannot determine the correct flow rate for your radiators. It is usually caused by a mechanical failure within the pump itself or a glitch in the main circuit board that prevents it from sending the correct speed signals. In some cases, a build-up of debris in the system can also put too much strain on the pump, causing it to fail this internal check.
This issue often comes to light in autumn when the heating is turned on for the first time after summer, as the pump can seize up 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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Could it be time for a new boiler?
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