High Lockout
F031 on Intergas Xtreme 24

Your boiler has stopped working because one of its internal temperature sensors is providing an incorrect reading 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 main control board detects a broken electrical circuit or an incorrect signal coming from the flow temperature sensor. The most common reason is that the sensor itself has developed an internal fault, though it can also be triggered by loose or corroded wiring in the harness. Because the boiler can no longer accurately monitor the heat of the water leaving the unit, it shuts down as a safety precaution.

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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