High
224 / E9 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected that it has become too hot and has automatically switched itself off to prevent any damage to the unit.

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

MAX thermostat activated

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 →224View →

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