Low
Neon I3 on Ideal Classic RS

Your boiler is receiving power and is ready to operate, as the 'I3' light simply indicates that the mains electricity 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.

Technical description

Mains electricity ON.

DIY fix possible

Check that your room thermostat is turned up to see if the boiler fires.Ensure the programmer/timer is set to 'On' or 'Auto'.No action is required if the boiler is working correctly, as this is a status indicator rather than a fault.

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