Low
Switched Live on Potterton Ultra 2 50 DV

This indicator light confirms that your boiler is receiving an electrical signal from your thermostat or timer to turn on and heat your home.

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

Indicator lamp 'On' - aids electrical commissioning

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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