Medium
S.41 on Vaillant ecoFIT Pure 425

Your boiler has detected that the water pressure inside the system is currently too high for it to operate safely.

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 that is easy to access.Use a radiator key to open the bleed valve slightly until a small amount of water drains out.Check the boiler's pressure gauge and stop bleeding when the needle sits within the green zone, typically between 1 and 1.5 bar.

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