Low
d.09 on Glow-worm MicraCom

Your boiler is simply displaying the temperature it has been told to reach by your smart thermostat or heating controller.

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

Target heating flow temperature that is set on the eBUS room thermostat

From this model's manual
Verified against the Glow Worm Micracom installation & service manual, page 40.
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 wall-mounted room thermostat or heating appObserve if the display changes when you adjust the temperature settingsNo action is needed as this is a normal status message, not a fault

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