High Lockout
F031 on Intergas Xclusive 24

Your boiler has stopped working because one of its internal heat sensors is reporting a technical error or has failed.

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

Sensor fault S1.

What causes this fault?

This fault occurs when the boiler's control board loses communication with the flow temperature sensor or receives an illogical reading. The most common reason is that the internal sensor has developed an electrical fault, or the wiring connecting the sensor to the main board has become loose or damaged.

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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Related fault codes

F030View →

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