Low
S.91 on Glow-worm Energy7 System

Your boiler has been accidentally set to a showroom display mode rather than operating as a normal home heating appliance.

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

Maintenance: Demo mode

Shared across the Energy7 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 the boiler's user interface screen.Access the installer menu by holding the mode button or referring to the specific display sequence in your user manual.Locate the 'Demo Mode' setting and switch it to 'Off' to return the boiler to normal operation.

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All 95 fault codes on the Energy7 System

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

ConnectionF.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.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91F.97F22P.01P.02P.03P.04P.05P.06P.07P.10S.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.76S.88S.96S.97S.98S.99S.108S.109

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