Low Information
NEON1 on Glow-worm Hideaway 40B

This light simply indicates that the boiler is receiving power and is switched on at the wall or spur.

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 ON

What causes this fault?

This is not actually a fault, but a status indicator showing that the boiler is successfully receiving electrical power from your home's mains supply. It confirms that the external fused spur or plug is switched on and that the internal control board is active. You will see this light whenever the boiler is ready to operate or is currently heating your home.

DIY fix possible

No action required as this is a status indicator, not a faultIf the boiler is not firing despite this light being on, check that your thermostat is turned upEnsure your programmer is set to 'ON' or 'AUTO'

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Related fault codes

NEON 2View →

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