High Lockout
24 on Potterton Performa System HE

Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has shut down as a safety precaution.

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

Fault on Temperature Sensor

What causes this fault?

This fault occurs when the boiler's control board loses communication with the temperature sensor or receives an unrealistic reading. The most common reason is that the internal thermistor has physically degraded over time or developed a short circuit, preventing the unit from monitoring heat levels safely. In some cases, it can also be caused by loose or damaged wiring connecting the sensor to the main circuit board.

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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