Low
I3 on Ideal Optimum 001

Your boiler is operating normally and is currently receiving power from your home's mains electricity 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

Mains electricity ON

From this model's manual
Verified against the Ideal Boiler Opt 001 installation & service manual, page 35.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

No action is required as this indicates the boiler is powered on and functioning as expected.

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