Medium Lockout
E12 on Intergas Combi Compact HRE 24/18

Your boiler's hot water sensor has failed or detected an error, meaning the system cannot accurately measure the temperature of your tap water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

DHW sensor S3 defective

What causes this fault?

This fault occurs when the domestic hot water sensor becomes damaged or begins sending incorrect electrical signals back to the main control board. The most common reason is internal wear and tear on the sensor's thermistor, though loose wiring or moisture ingress at the connection point can also trigger the error.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E02View →E05View →E13View →

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