High Lockout
F011 on Intergas Xtreme / Xclusive

Your boiler has detected a problem with its internal temperature sensors, meaning it cannot accurately measure how hot the water is and has stopped running 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

Sensor fault

What causes this fault?

This fault occurs when the boiler's internal computer receives an illogical or broken signal from the temperature sensors that monitor water flow. The most common reason is that a sensor has suffered an electrical failure or the wiring connecting it to the main control 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

F012View →F015View →

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