High Lockout
F015 on Intergas Xtreme / Xclusive

Your boiler has stopped working because one of its internal heat sensors has come loose or is not sitting correctly against the pipework.

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 main flow sensor, which monitors the temperature of the water leaving the boiler, loses physical contact with the internal pipework. The most common reason is that the Retaining clip has become loose or broken, preventing the sensor from getting an accurate reading and causing the boiler to shut down for safety. In some cases, it may also be caused by a faulty wiring connection between the sensor and the main control board.

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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