Medium
S.41 on Vaillant ecoFIT Pure 835

Your boiler has detected that the water pressure inside the heating system is currently too high, which may cause it to stop working to protect itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Water pressure too high

From this model's manual
Verified against the Vaillant Ecofit Pure 830 installation & service manual, page 33.
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

Locate the radiator closest to the boiler.Open the bleed valve on that radiator using a radiator key to release a small amount of water.Place a cloth underneath to catch drips and monitor the boiler's pressure gauge until it drops into the green zone (typically 1.0 to 1.5 bar).

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