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.

Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
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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All 4 fault codes on the Classic Se

Seeing a different code? Every code this model can display, in one place.

I3Neon SG1SG1

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