Low Information
NEON1 on Glow-worm Micron 50FF

Your boiler is receiving electrical power and is in standby mode or waiting for a signal to heat up.

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 your boiler has a healthy electrical supply. It means the appliance is sitting in standby mode and is simply waiting for a signal from your thermostat or programmer to start heating your home. If your heating isn't coming on while this light is showing, the issue is likely with your external controls rather than the boiler itself.

DIY fix possible

Check that your external room thermostat or programmer is turned up and calling for heatEnsure the boiler control knob is not set to the 'Off' positionWait a few minutes to see if the boiler begins its ignition sequence automatically

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Related fault codes

NEON 2View →NEON 3View →

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