High Lockout
E74 on Warmhaus Enerwa / Priwa

Your boiler has stopped working because it cannot correctly measure the temperature of the water inside the system.

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

Temperature sensor error.

What causes this fault?

This fault occurs when the boiler's internal computer loses communication with the temperature sensor, meaning it can no longer safely monitor how hot the water is. The most common reason is that the sensor has either worn out or suffered an electrical failure, but it can also be caused by loose or damaged wiring connecting the sensor to 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

E05View →

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