Medium
S.36 on Glow-worm 38cxi

Your boiler is currently idle because it is not receiving a signal from your thermostat or timer to turn the heating on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

No Heating demand from external controls 24V

From this model's manual
Verified against the Glow Worm Glow Worm 38cxi installation & service manual, page 52.
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 and ensure it is turned up to a temperature higher than the current room temperatureCheck that your programmer or timer is set to the 'On' position for heatingReplace the batteries in your wireless thermostat if applicableEnsure your smart heating hub or receiver is powered on and connected to your internet

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