High
Tank overheat on Worcester Bosch Greenstar i

Your hot water tank has reached an unsafely high temperature, and the boiler has shut down to prevent damage or scalding.

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

Tank sensor is correctly fixed to tank. Wiring and connections to sensor.

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

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