Unknown
b1 on Worcester Bosch Highflow 440 CDi

Worcester Bosch Highflow 440 CDi fault code b1

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Code plug not detected

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Highflow 440 Cdi 4740689 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 27 fault codes on the Highflow 440 CDi

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

6.46.56AA1A5A7A8b2b2, b3, b4, b5, b6b3b4b5b6b7C6d3d5d6E2E9EAF0F1F7FAFd

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