Low Information
Neon I3 on Ideal Classic HE

Your boiler has electrical power and is currently functioning normally, as this light simply indicates the mains power 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.

What causes this fault?

This is not a fault, but rather a status indicator showing that the boiler is successfully receiving electrical power from your mains supply. It confirms that the internal circuitry is live and the unit is ready to operate when there is a demand for heating or hot water. If the boiler isn't firing despite this light being on, the issue likely lies with your external thermostat or a different internal component.

DIY fix possible

Check if other control lights are flashing to indicate a real faultEnsure your room thermostat is turned up to call for heatNo action is required if the boiler is providing heating and hot water

Find a Gas Safe engineer
Search the official register →

Related guides you might find useful

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →