Low
S.00 on Glow-worm Ultracom hxi

Your boiler is currently idle because it has not received a request for heat from your thermostat or timer.

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

no heating required

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 room thermostat is set to a higher temperature than the current room temperatureEnsure your heating programmer or timer is set to the 'On' positionWait for the boiler to cycle on when the room temperature drops

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Related fault codes

S.01View →S.02View →

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.01S.04S.05S.06S.07S.31S.53S.54S.76

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