Low
Neon I3 on Ideal Classic Se

Your boiler is receiving power, but this indicator light is just confirming that the electrical supply is turned on and the system is in standby.

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.
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

Check your thermostat or programmer to ensure a heating or hot water demand is activeEnsure the central heating dial on the boiler front panel is turned upVerify that the boiler's external mode switch or timer is set to 'ON'

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