Attached is an example on what items need to be completed when changing a compressor on a larger VRF system. It is recommended that ALL compressors are changed with the oil separator, suction accumulator and the system flushed with burn outs


Service Procedure PRODUCT: VRF Outdoor units 


MODELS: S Series, V Series and V II Series SUBJECT: Correct compressor change 


1. Determine type of failure. 


2. Isolate power and tag. 


3. Reclaim refrigerant and weigh removed amount. If the removed amount is not equal to the amount recorded on the outdoor unit, pressure test the system and leak check. Only proceed once it has been confirmed that there is a leak and it has been repaired. If the pressure does not drop which indicates there is no leak, proceed to step 4. 


4. Disconnect compressor electrically from system. 


5. Perform oil test for acidity. If there is no acid present, proceed to step 7. 


6. If there is acid in the system, flush system and then install a replaceable core burn out drier on the suction line after the 3 way service valve. Also install a hand valve after the suction line drier to allow for easy replacement or removal. Make sure the hand valve is ‘solder in and has a Schrader valve somewhere between the two isolation points. Please use nitrogen while brazing. 


 


7. If there is no acid in the system, install a bi‐flow drier on the liquid line after the 3 way valve. Also install a hand valve after the drier to allow for isolation. Please ensure there is a Schrader valve somewhere between the two isolation points. Please use nitrogen while brazing (see diagram above). 


8. Remove the faulty compressor with nitrogen running through the pipe work to prevent oxidisation.


9. Install new compressor with the use of nitrogen. 


10. Pressure check with nitrogen. 


11. Evacuate system down to 500 microns or lower. 


12. Recharge system with refrigerant by weighing in with refrigerant scales as a liquid. 


13. Leak check all new joints. 


14. Reconnect compressor electrically to system. 


15. Remove danger tag and power up system.  


16. Reset error if required. 




17. Run system on TEST MODE to ensure correct operation. S and V Series: