Low
Mains On (Green) light flash on Potterton Performa SL HE 9 2

Your boiler is correctly receiving electrical power and is currently in standby mode, which is the normal operational state.

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 supply is On

DIY fix possible

Check your thermostat or programmer settings to ensure there is a demand for heating or hot waterEnsure the boiler's mode selector switch is set to the desired setting for heating and hot waterAdjust your room thermostat to a higher temperature to trigger the firing process

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