Low
357 on Worcester Bosch Greenstar CDi Compact

Your boiler is currently running an automated self-clearing process to remove trapped air from its internal system, which will finish on its own in about two minutes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Primary Heat Exchanger air venting program active - approx. 100 seconds

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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