Mine is precharged but it still requires to have the lines vacuumed. I did look into the ones with precharged lines like the mr.cool but when I went to the grow shop they offered me an amazing deal on the models they sell. I struggled with sizing, I had a 12k window unit and it didn't do things like I wanted but i think the mini with its better dehumidification, higher seer, and just design I will be in much better shape. I am also changing up my lights and dropping the wattage too. I ended up with a 12k again