BoilerFaultCodesTechnical description
Pump running
What causes this fault?
This code appears when the boiler begins a new heating cycle and starts the internal pump to move water through the system. It is a natural part of the startup process designed to ensure there is enough water flow before the burner lights. You will usually see this for a few seconds before the boiler settles into its normal heating mode.
DIY fix possible
Wait a few minutes for the boiler to complete its pre-ignition checksEnsure your thermostat is calling for heatCheck that your radiator valves are open
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