Low
P1 on Worcester Bosch Greenstar ZWB7

Your boiler is currently just running a routine internal safety check as it starts up, so please wait a few moments for it to finish.

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.

What the manual says

Manufacturer manual

Please wait, initialisation in progress.

From this model's manual
Verified against the Worcester Bosch Greenstar Zwb7 installation & service manual, page 43.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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