High Lockout
Fault 14 / 119 on Worcester Bosch Greenstar CDi Compact

Your boiler's internal computer is having trouble communicating with an external plug-in control or a hot water cylinder component.

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

System configuration: incompatible BUS device. IPM for cylinder must be set to identification 3 or higher.

What causes this fault?

This fault occurs when the boiler's main control board fails to communicate correctly with an external component, such as a hot water cylinder sensor or a plug-in timer. The most common reason is a configuration error where the electronic 'address' of a connected device is set incorrectly, causing the system to stop as a safety precaution. It can also be triggered by loose wiring or a failing control module that can no longer send clear signals to the central computer.

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 →B7View →F7View →

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