High Lockout
f016 on Intergas Xclusive 24

Your boiler has detected an internal communication error or a connection issue with a thermal sensor, causing it to shut down for safety.

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

Mounting fault S3

What causes this fault?

This fault occurs when the boiler's control board loses signal or receives an incorrect reading from a specific internal temperature sensor. The most common reason is that the sensor itself has failed due to wear, or the wiring connecting it to the main computer 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

F011View →F015View →

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