Medium
S.41 on Vaillant ecoFIT Pure 435

Your boiler has detected that the water pressure inside your heating system is currently too high for safe operation.

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 a radiator in your home, preferably on the ground floor.Using a radiator bleed key, open the bleed valve slightly until a small amount of water comes out.Check your boiler display to see if the pressure has dropped back into the recommended green range.

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