Medium
S.41 on Glow-worm Ultimate3 Combi

Your boiler has detected that the water pressure inside the 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

Waterpressuretoohigh

From this model's manual
Verified against the Glow Worm Ultimate3 Combi installation & service manual, page 45.
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 valve.Place a cloth and container underneath the valve.Slowly open the valve to bleed out a small amount of water until the boiler pressure gauge drops to the green zone (typically 1.0–1.5 bar).Close the valve tightly.

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