Low
P.05 on Glow-worm Ultracom 2 SXI

Your boiler is currently in the process of automatically or manually filling its internal water system.

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 appliance

Shared across the Ultracom 2 SXI 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 a few moments for the filling cycle to finish automatically.Check your system pressure gauge to see if it reads between 1 and 1.5 bar.If the filling does not complete, consult your manual to use the filling loop.

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Related fault codes

P.04View →F.22View →

All 75 fault codes on the Ultracom 2 SXI

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

ErrF00F01F1F10F11F20F22F23F24F26F27F28F29F32F49F61F62F63F64F65F67F68F70F71F72F73F74F76F77F83F84F85F86P.01P.02P.03P.06P.07S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.53S.54S.96S.98

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