Low
d.24 on Vaillant ecoFIT Pure 425

Your boiler is currently reporting whether the internal water pressure switch is active or inactive, which is part of its normal checking process but may indicate an issue if the boiler stops working.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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.

What the manual says

Manufacturer manual

Status of the pressure monitor (off=Not switched, on=Switched)

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 30.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check the central heating pressure gauge on the front of the boilerIf the pressure is below 1.0 bar, use the external filling loop to top it up to 1.5 barEnsure all radiator valves are open and not blocked by air

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F.22View →F.24View →

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