Low
d.40 on Glow-worm Easicom 24

Your boiler is correctly reporting the current temperature of the water flowing into your heating system, and this code is simply providing information rather than indicating a failure.

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

Heating flow temperature

From this model's manual
Verified against the Glow Worm Easicom 24 installation & service manual, page 26.
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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