High
FAULT POINT B on Worcester Bosch 15 CBi

Your boiler is receiving a signal for heating or hot water, but the burner is failing to ignite.

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

DEMAND LIGHT ONLY

From this model's manual
Verified against the Worcester Bosch/Worcester Bosch Greenstar 15sbi 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 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

EAView →D5View →

All 8 fault codes on the 15 CBi

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

FAULT POINT AFAULT POINT CFAULT POINT DFAULT POINT EFAULT POINT FFlashing lightSteady light

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