High
224 on Worcester Bosch Greenstar 2000

Your boiler has detected that it is running too hot and has automatically shut itself down to prevent any 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.

What the manual says

Manufacturer manual

Safety temp. limiter has tripped. Check lead, high limit, system pressure, air in system, pump, or blockages.

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 79.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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