High Lockout
Fault 13 / 157 on Worcester Bosch Greenstar CDi Compact

Your boiler's computer system has detected a change in its connected parts or settings and needs to be told how to recognize them again.

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: BUS device changed or replaced. Check system configuration for DHW or start automatic system configuration.

What causes this fault?

This fault occurs when the boiler's internal computer loses track of the sensors or external controls it is supposed to be talking to. It most commonly happens after a power cut, a software update, or if a new part has been installed but the boiler hasn't been properly introduced to it yet.

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

208View →E9View →

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