Low
S.31 on Glow-worm Ultracom hxi

Your boiler is currently set to summer mode, which means it is waiting for a request for hot water but will not provide central heating.

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

summer mode

Shared across the Ultracom 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

Check your programmer or room thermostat settings.Ensure your heating controls are set to 'ON' or 'Timed' rather than 'Off' or 'Summer'.Adjust the heating dial on the front of the boiler to a higher temperature if it is currently set to zero.

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Related fault codes

S.30View →S.32View →

All 23 fault codes on the Ultracom hxi

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

Connectiond.27d.28d.91d.92d.99F.10F.13F3F4F6F14F15S.00S.01S.04S.05S.06S.07S.53S.54S.76

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