Ok so long story short, my dad (old guy) installed a cheap mini split system a couple days ago and basically just hooked everything up, opened the valves and away he goes. He says it's working good but I know he was supposed to get it vacuumed and tested before start up. I will pay a guy to go to his place (out in the boonies) but my question is has any potential damage already been done? What if anything should be done at this point? Being that it was a cheap system is it even worth it now? Please don't berate my dad in your replies, he means well, I'm just trying to help him out. Thank you.