Low
I3 on Ideal Classic Se

Your boiler is simply showing that it has a stable power supply and is ready to operate as normal.

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 Classic Se9ff Se12ff Se15ff Se18ff Se21ff Se24ff Se30ff installation & service manual, page 29.
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 is a status indicator, not an error.If the boiler is not working despite this light, check your thermostat settings or external heating programmer.

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