BoilerFaultCodesYour boiler is currently warming itself up and checking that water is flowing correctly before it starts heating your home.
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: Water pump flow
What causes this fault?
This code appears when the boiler is running a brief pre-check to ensure there is sufficient water pressure and flow before the main burner ignites. It is caused by the internal pump building up pressure to confirm the system is safe to operate. If this code stays on the screen for a long time, it could indicate that air is trapped in the system or the pump is struggling to move water effectively.
DIY fix possible
Check that your radiator valves are openEnsure the boiler pressure is between 1.0 and 1.5 barWait a few minutes to see if the code changes to a normal heating mode
Find a Gas Safe engineer
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A boiler cover plan would cover faults like S.2 — no call-out fees, no surprises.
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