Low
d.09 on Glow-worm Compact

Your boiler is simply displaying the current temperature setting requested by your room thermostat, rather than indicating a fault.

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 Compact 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 room thermostat settings to see if the temperature displayed matches your desired comfort levelWait a few moments as the boiler will automatically return to its normal display mode

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