High Lockout
29 on Potterton Performa 30 HE

Your boiler has detected a problem with the sensor that monitors the temperature of the water used for your radiators, causing the heating to stop working.

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 Central Heating Sensor

What causes this fault?

This fault occurs when the boiler's internal computer receives an incorrect or missing signal from the sensor that monitors your radiator water temperature. The most common reason is that the sensor has physically failed due to age, though it can also be triggered by loose or corroded electrical connections between the sensor and the main control 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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