BoilerFaultCodesYour boiler has detected that hot water is being called for, but it believes the pump is running when it shouldn't be or there is a circulation issue preventing proper operation.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: DHW demand – error pump running
What causes this fault?
This fault occurs when the boiler detects a conflict in the heating water flow while trying to provide hot water. It usually means the internal pump is stuck in the ‘on’ position or a sensor is sending incorrect signals to the main control board about water movement. This prevents the boiler from safely managing the temperature, leading to a shutdown to protect internal components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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