High
A7 on Worcester Bosch Ri 25 HE

Your boiler is struggling to accurately detect the temperature of the water being used, which will likely prevent you from having hot water until it is fixed.

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 NTC sensor defective.

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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