High Lockout
Fault 29 / 202 on Worcester Bosch Greenstar CDi Compact

Your boiler's internal computer has lost communication with one of its key control modules, meaning it cannot save or follow its programmed settings.

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.

Technical description

Unable to save parameter settings: BUS device is configured but not available at present.

What causes this fault?

This fault occurs when the boiler's main control board loses the electronic link to an internal or external accessory it expects to find. It is usually caused by a loose connection in the wiring harness or a critical failure of the internal circuit board that stores your heating settings.

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

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