High
BCC Fault on Keston Heat 45

Your boiler's internal memory chip is not communicating correctly with the main control board, which prevents the unit from starting or running reliably.

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

Ensure BCC fitted correctly, Replace BCC

From this model's manual
Verified against the Keston Heat 45 installation & service manual, page 53.
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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