High Lockout
f015 on Intergas Xclusive 24

Your boiler has detected that a temperature sensor is not properly attached or is incorrectly mounted, preventing the system from heating up safely.

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 sensor S1

What causes this fault?

This fault occurs when the boiler's main flow temperature sensor has physically shifted or detached from the internal pipework. Because the sensor can no longer accurately measure how hot the water is, the system shuts down to prevent the boiler from overheating. This is often caused by a weakened retaining clip or vibration over time loosening the sensor's connection.

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

F010View →F011View →

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