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

Your boiler has automatically turned itself off because internal sensors detected it was getting too hot, likely due to a flow restriction or a faulty sensor.

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

Overheat Lockout - an overheat condition occurs

Shared across the Performa range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 17 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 FaultE01Electrical Supply FaultFalse Flame FaultFlow Thermistor FaultIgnition LOCKOUTLockout (Red) flashingLockout (Red) light onMains On (Green) light flashOverheat LOCKOUTPCB FaultWater Circulation LOCKOUT

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