High Lockout
21 on Intergas Compact HRE OV

Your boiler has detected a problem with one of its internal temperature sensors, which prevents it from heating your home or water 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

Sensor fault S2

What causes this fault?

This fault occurs when the boiler's internal computer receives an incorrect or missing signal from the return temperature sensor. The most common reason is that the sensor itself has worn out and failed, though it can also be caused by loose wiring or water damage to the electrical connections inside the casing.

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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