BoilerFaultCodesYour boiler is performing a routine self-check of the internal pump before it starts the main heating process.
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: Pump pre run
What causes this fault?
This status occurs as part of the boiler's normal start-up sequence to ensure the internal pump is moving water correctly before the burner ignites. It is not a breakdown, but rather a safety and efficiency check to prevent the heat exchanger from overheating. If this code stays on the screen for a long time, it may suggest that the pump is struggling to reach its required speed or there is air trapped in the system.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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