Low Information
P1, P2, P3, P1... on Worcester Bosch Greenstar 25HE

Your boiler is simply going through its normal startup and self-test sequence after being turned on or reset.

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.

What causes this fault?

This sequence occurs when the boiler's internal computer begins its startup and safety checks after the power has been switched on or the reset button pressed. It is not a fault, but rather the boiler confirming all internal components are communicating correctly before it begins the ignition process. Think of it like a computer booting up its operating system before it is ready for use.

DIY fix possible

Wait for approximately 30 to 60 seconds for the sequence to finishEnsure the boiler power is left switched onIf the code persists for more than 5 minutes, try a single reset

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