High
OVERHEAT LOCKOUT on Potterton Promax FSB 30HE

Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage to its internal components.

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.

Technical description

Lights: On Off * Off. Possible causes: Flow pipe thermostat (stat) failure, fan stat failure, thermistor (red sensor on flow pipe) failure, combustion chamber door seal damaged, or PCB failure.

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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