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

Shared across the Ultimate 3 range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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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Related fault codes

F.22View →F.73View →

All 159 fault codes on the Ultimate3 Combi

Seeing a different code? Every code this model can display, in one place.

d.00d.01d.02d.04d.05d.06d.07d.08d.09d.10d.11d.13d.14d.15d.16d.17d.18d.19d.20d.21d.22d.23d.24d.25d.27d.28d.31d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.62d.64d.65d.66d.67d.68d.69d.70d.71d.73d.75d.77d.80d.81d.82d.83d.84d.85d.88d.90d.91d.93d.94d.95d.96F.00F.01F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.77F.78F.83F.84F.85F.86F.87F.88F.89F.97F2F22P.01P.02P.03P.04P.05P.06P.07Pump OverrunS.0S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.39S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109

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