Low
1023 on Worcester Bosch Greenstar 1000

Your boiler has been running for a very long period without a break and has automatically paused to prevent overheating.

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 Worcester Bosch Greenstar 1000 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.

What causes this fault?

Operating hours limit reached

DIY fix possible

Switch the boiler off at the mains power supplyWait for 60 seconds to allow the system to resetSwitch the power back on and observe if normal operation resumes

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