High
Lockout (Red) light on on Potterton Performa SL HE 9 2

Your boiler has stopped working because it couldn't light the flame, which means your heating and hot water will not turn on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Ignition Lockout - boiler failed to light after five attempts

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.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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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 flashMains On (Green) light flashOverheat LOCKOUTPCB FaultWater Circulation LOCKOUT

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