Just purchased car and A/C air not cold :(

No that's not how this works without a full charge of gas or either overcharging it and letting some out on the high side whatever A lot of these guys here worry about this kind of stuff and well I don't but if there's not enough refrigerant in your system the electric compressor has the capability to speed up and slow down and it will wind itself out trying to pump nothing is just enough to turn the low pressure switch off it thinks the system is gassed up and ready to go and it starts trying to pump the pressures with what's in the pipes that it needs to make which is like over 200 on the high side to 40 to 50 depending upon temperature and all kinds of nonsense and that low side's going to try and stay 37 to 41 42 somewhere in there. Has your system slowly leaks past o rings and all of that stuff plus there's a built-in government number that you're allowed to leak per year per type of system you have You can Google that stuff. As your system leaks down The compressor is slowly having to ramp up more and more and more It has nothing to do with your fan speed selection to get the cabin colder the fan runs longer The coil doesn't get any colder the evaporator in the car in the dash It gets to a certain temperature and there you go to make the cabin more cold You're just running the fan longer and the compressor is running longer and keeping the cold coming if you will You won't notice your compressor starting to wind up You're too busy enjoying the cold listening to the radio talking on the phone and driving the car it'll slowly inch up as gas gets out there's no worries about cracking a line and letting the little bit of gas left in the system out and then just going ahead and replacing the o-rings If you want to go someplace and have them vacuum the system down and all this and that by all means you'll have to pay for it your little fart of 1:34A is not going to change anything on the planet but whatever you need to do get it sucked out take it home and place the o-rings thread everything up properly pull a vacuum on it with a vacuum pump and drop in the 1.3 lb of Freon and it's really not too difficult to do then once you're pretty well sealed up You should be good for a while.