High Lockout
F000 on Intergas Xclusive 24

Your boiler has stopped working because an internal temperature sensor has failed and can no longer monitor the heating water.

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 S0 is defective.

What causes this fault?

This fault occurs when the boiler's primary temperature sensor becomes unable to send an accurate electrical signal to the main control board. The most common reason is the internal thermistor failing due to age or heat stress, though it can also be caused by loose or damaged wiring connections inside the unit.

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

F001View →

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