High Lockout
F030 on Intergas Xtreme 24

Your boiler has stopped working because one of its internal temperature sensors is providing an incorrect reading or has developed a fault.

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 S3.

What causes this fault?

This fault occurs when the boiler’s internal control system receives an illogical or out-of-range signal from the S3 temperature sensor. The most common reason is that the sensor itself has suffered an electrical failure or the wiring connecting it to the main circuit 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

F031View →

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