That there is a sealed black box with ALL the A/C components is gibberish. The compressor can't be in that box - it's driven by a belt off the engine. The climate control unit can't be in that black box - it's in the passenger cabin. You still don't have an intelligible diagnosis, but I wouldn't spend too much time trying to figure out what these people are saying - you wouldn't want them working on the car anyway. You need to start over with a proper diagnosis from a legitimate shop, or do it yourself. If indeed there is no such thing where you live you, and you are unwilling to get involved, you should probably consider getting rid of the car.