Unknown
11 on Worcester Bosch Greenstar Ri

Worcester Bosch Greenstar Ri fault code 11

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

HCM (Heat Control Module) Defective

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Zb 7 27 He System installation & service 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 15 fault codes on the Greenstar Ri

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

1 (Group 1)2 (Group 1)3 (Group 1)4 (Group 1)5 (Group 1)67891012131415

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