Low
P.05 on Glow-worm Ultimate 3 25R

Your boiler is currently refilling its internal water system, which is a normal process that happens automatically if the water pressure has dropped.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Filling the product

Shared across the Ultimate 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

Wait 5-10 minutes to see if the boiler completes the automatic fill process.Check your system pressure gauge; it should be between 1.0 and 1.5 bar.If the code persists for more than 30 minutes, check your external filling loop valves are fully closed.

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Related fault codes

F.22View →F.73View →

All 159 fault codes on the Ultimate 3 25R

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

Connectiond.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.12F.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.91F22P.01P.02P.03P.04P.06P.07S.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.41S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109

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