Medium
d.08 on Glow-worm Energy7 Combi

Your boiler is currently receiving a signal from your thermostat that it is time to heat up, but there may be a loose connection or a fault in the communication between your wall controller and the boiler.

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

Status of the 230V 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 external room thermostat is set correctly and the batteries are fresh.Ensure the thermostat wiring at the boiler terminal block is securely connected and not loose.Power cycle the boiler by switching it off at the fused spur for one minute, then turning it back on.

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