Low
P.03 on Glow-worm Energy

Your boiler is currently running at its maximum power setting to heat your home, which is a normal operational state rather than a fault.

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

The product runs in heating mode with the maximum heat input set using diagnostics code d.00.

From this model's manual
Verified against the Glow Worm Energy installation & service manual, page 28.
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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