BoilerFaultCodesWhat the manual says
Manufacturer manualpump pre-run
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This status occurs when the boiler detects a demand for heat and starts the internal pump to move water through the heat exchanger. It is a vital safety check designed to ensure there is sufficient water flow before the burner ignites to prevent the system from overheating. Once the electronics confirm the water is circulating correctly, the boiler will proceed to the ignition stage.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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Related fault codes
All 52 fault codes on the Flexicom hx
Seeing a different code? Every code this model can display, in one place.