Low
0-A2 on Worcester Bosch Greenstar 2000

Your boiler is operating in a service mode used for manual testing and checking heating temperatures.

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

Set temperature in manual operation: 30...60...82°C.

Shared across the Greenstar 2000 range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

Check if the service button or chimney sweep mode has been accidentally activated.Turn the boiler off and back on at the main power switch to reset the control panel.Adjust the temperature dial or digital controls to exit the manual override menu.

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Related fault codes

All 235 fault codes on the Greenstar 2000

Seeing a different code? Every code this model can display, in one place.

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