High
A7 on Worcester Bosch Highflow 550 CDi

Your boiler has lost the signal from the sensor that monitors your hot water temperature, which means it cannot accurately heat your water.

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

Hot water sensor 1 temperature interrupted

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

A8View →E9View →

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