Low
1023 on Worcester Bosch Greenstar 27CDi

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.

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

Maximum run time including standby time reached

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 84.
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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