BoilerFaultCodesYour boiler is simply preparing its internal pump before starting the heating process, which is a normal part of its operation.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Heatingmode:Pumppre-run
What causes this fault?
This code appears when the boiler's control board sends power to the internal pump to begin circulating water before the burner ignites. It is a brief safety and efficiency check designed to push any air or cold water out of the heat exchanger. This is a normal part of the start-up sequence and does not mean your boiler has broken down.
DIY fix possible
No action is required as this is a status code, not a faultWait a few moments for the boiler to complete its pre-run cycleCheck that your thermostat is calling for heat if the boiler stays in this state
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