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

Your boiler is currently going through a startup and self-test sequence, which usually happens after it has been switched back 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 is triggered when the boiler is first powered on or has just been reset. It represents the internal computer checking all sensors and safety components to ensure the system is safe to fire up. The boiler isn't broken; it is simply performing a routine 'handshake' between its electrical parts.

This display is frequently seen in winter following a power cut or when a homeowner resets the boiler after a frozen condensate pipe has been cleared.

DIY fix possible

Wait for approximately 5 to 10 minutes for the sequence to completeEnsure the boiler power switch is in the 'on' positionIf the code persists for over 30 minutes, try pressing the 'Reset' button once

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