Low
357 on Worcester Bosch Greenstar 28CDi

Your boiler is currently running a brief automatic safety check of its internal air and exhaust system before it attempts to fire up.

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

Ventilation program

Engineer required

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

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