Low
P.04 on Glow-worm Energy7 System

Your boiler is currently running in a special testing mode, often used by engineers to check combustion levels, which will automatically turn off after 15 minutes.

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

Chimney sweep function: If there is a domestic hot water demand, the product runs in domestic hot water mode with maximum heat input. If there is no domestic hot water demand, the product runs in heating mode with the partial heat load that is set using diagnostics code d.00. The function is activated for 15 minutes.

From this model's manual
Verified against the Glow Worm Energy7 System installation & service manual, page 45.
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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