High Lockout
E11 on Intergas Combi Compact HRE OV

Your boiler has detected a problem with one of its internal temperature sensors, which prevents it from monitoring the water returning to the unit correctly.

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

Return sensor S2 defective

What causes this fault?

This fault occurs when the boiler's control board loses communication with the sensor that monitors water coming back from your radiators. This is typically caused by the internal component failing due to age or a loose connection in the electrical wiring, meaning the boiler can no longer safely regulate its temperature.

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

E02View →E05View →E10View →

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