Medium
S.41 on Glow-worm Energy System

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 Energy System 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 is easily accessibleAttach a bleed key to the radiator valve and open it slowly until water starts to drip outMonitor the pressure gauge on your boiler until it drops back into the green zone (usually 1.0 to 1.5 bar) and then tighten the valve

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F.22View →S.42View →

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