Low
d.08 on Glow-worm Ultimate 3 25R

Your boiler is currently waiting for a signal from your wall thermostat or timer to tell it to turn on.

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 230V thermostat

From this model's manual
Verified against the Glow Worm Ultimate 3 25r installation & service manual, page 29.
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 temperature.Ensure your timer or programmer is set to 'on' or in a timed period.Replace the batteries in your room thermostat if it is wireless.

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Related fault codes

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