Medium
d.41 on Glow-worm Ultimate3 Combi

Your boiler is struggling to accurately measure the temperature of the water returning from your radiators, which may cause it to switch off to prevent overheating.

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

Heatingreturntemperature

From this model's manual
Verified against the Glow Worm Ultimate3 Combi installation & service manual, page 43.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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d.40View →F.20View →

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