Low Information
Neon I3 on Ideal Mexico Super 40ff - 80ff

Your boiler has electrical power and is ready to operate as normal; this light is a status indicator rather than a fault.

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

What causes this fault?

This is not a fault, but a signal that your boiler is receiving electrical power from your home's mains supply. It indicates that the internal control board is live and the appliance is ready to start the ignition sequence as soon as your thermostat calls for heat. If the boiler isn't firing despite this light being on, the issue usually lies with your external controls or pump rather than the boiler itself.

DIY fix possible

No action required if the boiler is heating correctlyIf the boiler is not firing, check that your room thermostat is turned upEnsure your programmer or timer is set to an 'ON' period

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