High
2966 on Worcester Bosch Greenstar 8000 Life Regular

Your boiler has detected that the water inside is heating up far too quickly, which usually suggests a restricted flow preventing heat from moving away from the burner correctly.

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

Flow temperature rise in heat exchanger too rapid | 1. System is not filled with water... 3. No water flow, because pump is not operating correctly.

Shared across the Greenstar 8000 range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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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Related fault codes

2965View →227View →

All 107 fault codes on the Greenstar 8000 Life Regular

Seeing a different code? Every code this model can display, in one place.

1-A21-d31-d41-E11-E21-E31-E41-EA1-Eb2002012022032042082142242272282292322332342352372382422442452462472482492502512522532542572582592622632652682692732812832843063573583603623636048151010101310181019102210231025103710681070107110721075107620852908291029142915291629202923292429252926292729282931294029462948294929502951295229552956295729612962296329652965 B2966 B296829692972D4

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