Low
d.25 on Glow-worm Energy7 Combi

Your boiler is simply indicating that it has received a signal from your thermostat to heat your water or keep it warm for a faster supply.

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 requirement to reheat the cylinder or for the domestic hot water warm start from the eBUS thermostat

From this model's manual
Verified against the Glow Worm Energy7 Combi installation & service manual, page 48.
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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Related fault codes

d.26View →d.27View →

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