Medium
S.41 on Vaillant ecoFIT Pure 830

Your boiler has detected that the water pressure inside your heating 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 with a bleed valveUse a radiator key to slightly open the valve and release a small amount of water into a containerMonitor the pressure gauge on the front of your boiler until it drops back into the green zone (usually 1.0 to 1.5 bar)Close the valve tightly once the pressure is correct

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