522 error code
NTC drift test running
What does Worcester Bosch Greenstar 1000 gas boiler 522 mean?
Worcester Bosch documents code 522 on the Greenstar 1000 as “NTC drift test running”. This is an operating status rather than a fault and normally describes what the boiler is doing. The code meaning is model-specific, so it should not be applied to a different Worcester Bosch range without checking that product's manual.
The code identifies the condition detected by the product; it does not always identify the failed component on its own. Confirm the full code and exact model before ordering parts or attempting a reset.
The Worcester Bosch Greenstar 1000 gas boiler 522 error code indicates worcester Bosch documents code 522 on the Greenstar 1000 as “NTC drift test running”. This is an operating status rather than a fault and normally describes what the boiler is doing. The code meaning is model-specific, so it should not be applied to a different Worcester Bosch range without checking that product's manual. This guide explains what the code means, the symptoms and likely causes, the checks that are safe to make, and when to stop and arrange an authorised repair.
Symptoms you may notice
- The Greenstar 1000 display shows code 522.
- The boiler may continue operating because this code can describe a normal operating state.
- The display behaviour and any accompanying symbols depend on the fault category and appliance state.
- The same numeric code can have a different application on another Worcester Bosch product, so confirm the model label first.
Common causes
- NTC drift test running
- A normal control sequence or current demand state.
- The precise cause cannot be confirmed from the display code alone; wiring, sensors, circulation, combustion and control components require model-specific diagnosis.
Before you start troubleshooting
Use the display, rating label or product menu to confirm the exact model. Similar-looking codes can have different meanings across product generations and regions.
- Record the complete code before switching the equipment off.
- Check only user-accessible controls, filters and external connections described in the manual.
- Do not open gas, refrigerant, combustion or electrical compartments.
Troubleshooting steps
- Record code 522, any accompanying symbol and whether the boiler was heating, producing hot water or starting up.
- Confirm the appliance is a Worcester Bosch Greenstar 1000 and read the fault history where the user instructions permit.
- Check only external items described in the operating instructions, including the system pressure display and whether power and gas supplies are available.
- Allow the documented operating sequence to complete and monitor whether the display returns to normal.
- Contact Worcester Bosch support if the status persists beyond the period described in the manual or normal operation does not resume.
Can you fix this error code yourself?
This code may be resolved with the documented user checks. Work through them once, in order, and confirm that normal operation returns.
A successful reset is not proof that the underlying issue is fixed. If 522 reappears, note when it happens and give that information to the service engineer.
Reset instructions
A reset is not normally required for an operating-status code. Follow the Greenstar 1000 operating instructions and allow the active sequence to finish.
Applicable products and models
Greenstar 1000 gas boilerGreenstar 10002023 onwardsWhen to contact a professional
Contact Worcester Bosch support or a qualified heating engineer if the status does not clear, the boiler stops providing heat or hot water, or another fault code appears.
Frequently asked questions
What does Worcester Bosch Greenstar 1000 gas boiler 522 mean?
Worcester Bosch documents code 522 on the Greenstar 1000 as “NTC drift test running”. This is an operating status rather than a fault and normally describes what the boiler is doing. The code meaning is model-specific, so it should not be applied to a different Worcester Bosch range without checking that product's manual.
Can I fix Worcester Bosch Greenstar 1000 gas boiler 522 myself?
The documented external checks may resolve this code. Follow them in order and stop if the fault returns.
Should I reset the product after code 522?
A reset is not normally required for an operating-status code. Follow the Greenstar 1000 operating instructions and allow the active sequence to finish.
When should I arrange a repair?
Contact Worcester Bosch support or a qualified heating engineer if the status does not clear, the boiler stops providing heat or hot water, or another fault code appears.