do you have to pull vacuum on A/C system?

Hello, yes after any repair on the A/C system where the refrigerant has been evacuated, the system needs to be pulled into a vacuum to get all the air and moisture out of the system before being refilled. And the exact amount of refrigerant needs to be added. There should be a tag in the engine compartment that has the A/C system information.

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system