Medium
S.41 on Glow-worm Ultimate 3 25R

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 Glow Worm Ultimate 3 25r 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 valve.Use a radiator key to open the valve slightly until a small amount of water escapes.Close the valve once the pressure gauge on the front of the boiler drops back into the green zone (usually between 1.0 and 1.5 bar).

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