Medium
S.41 on Glow-worm Essential

Your boiler has detected that the water pressure inside the system is currently too high, which may cause it to stop working to protect the internal components.

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 Essential installation & service manual, page 34.
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.Open the bleed valve slowly to release a small amount of water until the pressure gauge on the boiler drops to between 1 and 1.5 bar, then close the valve tightly.

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