Low
1023 on Worcester Bosch Greenstar 2000

Your boiler has been running for a very long time without a proper break, likely due to a system management setting or a sensor error, and needs a reset to clear the accumulated timer.

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

Maximum run time including standby time reached

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

Locate the reset button or dial on the boiler front panelPress and hold the reset button for 3 to 5 secondsWait for the boiler to cycle through its startup routineIf the code persists, turn the boiler off at the mains for 10 minutes before turning it back on

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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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