Low Information
P6 on Worcester Bosch Greenstar 25HE

Your boiler is simply performing a routine internal check as it starts up and the code should disappear after a few seconds.

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

Part of the self-test sequence sequence when the appliance is switched on.

What causes this fault?

This code appears when the boiler is first powered on or restarted, serving as a sign that the internal control board is running a diagnostic check. It occurs as the software verifies that all safety sensors and electronic components are communicating correctly before allowing the burner to light. It is not a malfunction, but rather a necessary step in the appliance's normal startup routine.

DIY fix possible

Wait for 30-60 seconds to see if the code clears automaticallyEnsure the power supply to the boiler is stableReset the boiler if the code remains on the screen for more than 2 minutes

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