Medium
S.41 on Vaillant Home Combi

Your boiler is reporting that the internal water pressure is higher than it should be, which may cause it to stop working to protect the system.

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

Waterpressuretoohigh

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 35.
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 has a bleed valve.Place a cloth or small container under the valve.Slowly open the valve with a radiator key to let a small amount of water out until the pressure gauge on the front of your boiler reads between 1.0 and 1.5 bar, then close the valve tightly.

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