High
E9 on Worcester Bosch Greenstar R29 40 HE

Your boiler has detected that it is getting 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 in flow has tripped. Check system pressure, check safety temp. limiters, check pump operation, check fuse on pcb, bleed appliance.

From this model's manual
Verified against the Worcester Bosch Greenstar 25he installation & service manual, page 104.
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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