Low
Neon I3 on Ideal Classic Slimline FF 330 360

This light simply indicates that there is power reaching the boiler and it is switched on.

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 Classic Slimline Ff 330 360 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.

What causes this fault?

This is not actually a fault, but a confirmation that your boiler is receiving electrical power from the main supply. It indicates that the internal circuitry is live and the appliance is ready to start the ignition process once there is a demand for heating or hot water. If this light is off, it usually means there is a tripped fuse, a blown internal fuse, or the isolation switch has been turned off.

DIY fix possible

Check that the boiler power switch is onEnsure no other fault lights are flashingMonitor the boiler for normal operation

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