Emergency
OVERHEAT LOCKOUT on Potterton Promax 15/2 HE Plus

Your boiler has automatically shut down because it has detected that it is getting dangerously hotter than it should be.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Lights: Flash Off On. Possible causes: black stat on flow pipe faulty, fan stat faulty, wiring from PCB to thermostats faulty, thermistor faulty, or combustion chamber door seal damaged.

Engineer required

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

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Related fault codes

E110View →E160View →

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