Do I need to add the Pag oil?

Yes, you do need to add oil when the system has a major pressure issue such as a hose failure. This can be a little tricky, you must estimate the amount of oil that came out of the system in ounces and then use an AC oil change can, to add oil or just pour it in when system is apart. If you vacuum the system down, it will not out the oil out of the system completely so you can start from scratch.

Here is a video to help:

https://www.youtube.com/watch?v=4EqdrBVb0sY&t

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