Low
1023 on Worcester Bosch Greenstar 8000 Style System

Your boiler has been running for a long continuous period and needs to be reset to ensure its internal monitors can perform a safety self-check.

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 8000 Life Style installation & service manual, page 78.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler has been powered on for a very long duration without a break, causing it to reach its programmed software limit for continuous operation. It happens because the system needs to briefly power down and restart to perform essential internal safety tests and recalibrate its sensors. A simple manual reset allows the boiler to complete these checks and return to normal operation.

This code is slightly more common in winter when boilers are under heavy demand and running constantly to maintain home heating without reaching their standby state.

DIY fix possible

Locate the 'Reset' button on the boiler control panel.Press the reset button once.The boiler should restart and resume normal operation.

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