Low
0-A1 on Worcester Bosch Greenstar 2000

Your boiler has been manually switched off or into a service mode and simply needs to be restarted or reset to resume normal operation.

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

Manual operation: OFF/ON.

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the main Power/Reset button on the boiler control panel.Press and hold the Reset button for 3 to 5 seconds.Wait for the boiler to complete its startup sequence and return to the home screen.

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