High
Heatbank Overheat Stat on Worcester Bosch Highflow 550 CDi

Your boiler has detected that the water storage tank has become too hot and has automatically shut down to prevent damage or safety issues.

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

Tripped. All functions stopped. Investigation of reason/reset required.

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

E9View →EAView →

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