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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.

What the manual says

Manufacturer manual

Mains electricity supply is On

From this model's manual
Verified against the Potterton/Potterton Performa Sl He 9 2 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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All 16 fault codes on the Performa SL HE 9 2

Seeing a different code? Every code this model can display, in one place.

Air Proving LOCKOUTAPS Stuck FaultBurner On (Green) light flashBurner On (Green) light onCasting Thermistor FaultElectrical Supply FaultFalse Flame FaultFlow Thermistor FaultIgnition LOCKOUTLockout (Red) flashingLockout (Red) light flashLockout (Red) light onOverheat LOCKOUTPCB FaultWater Circulation LOCKOUT

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