Low
d.16 on Glow-worm Energy7 Combi

Your boiler is currently waiting for a signal from your wall-mounted thermostat to tell it to turn on the 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

Status of the 24V room thermostat

From this model's manual
Verified against the Glow Worm Energy7 Combi installation & service manual, page 47.
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 that your wall thermostat is set to a temperature higher than the current room temperatureReplace the batteries in your room thermostat if it is wirelessEnsure the thermostat is not set to a 'Summer' or 'Off' mode

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