Most UV dyes sit in with the refrigeration oil of the unit. This can make it take more time for oil to circulate system and then you may need to wait a few days to see leaks. Clip light makes a product called UV Flash Dye.

This product flashes with the refrigerant and results happen within a half hour.

This product works good with Mini splits. Mini splits tend to have good oil separation, and they won't show typical dye as much. 

Products Needed:

 B17-319 980 FLASH UV DYE

B17-320 20122 FLASH HOSE

Each can, can treat up to 5 tons.