Low
S.28 on Glow-worm Energy7 Combi

Your boiler has temporarily paused the burner while heating your tap water to prevent it from getting too hot, and it should restart automatically once the temperature drops.

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

Domestic hot water mode: Temporary shutdown of the burner

From this model's manual
Verified against the Glow Worm Energy7 Combi installation & service manual, page 51.
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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