Low
P1, P2, P3, P1... on Worcester Bosch Greenstar System

Your boiler is simply performing a routine internal check-up as it starts up, so there is no need to worry.

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

Please wait, initialisation in progress.

Engineer required

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

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