When did you buy this mini split? The reason I ask is you can't buy a unit charged with R-22 anymore. They still sell R-22 units but they can't precharge them, they have to be sold "dry". Are you actually sure it's an R-22 unit? If so I'd assume it would be empty. (unless there's some loophole allowing them to sell R-22 mini splits I'm not aware of) In which case it definitely would need to be charged. But first i'd verify it even takes R-22.