How can you recharge the ac in a 2007 Chevy uplander?

Hi

First off did you fix the leak? next you must evacuate the system with a vacume pump

and then add freon 134A if your system is just low on freon it will automatically stop running. you can check that by taking the electrical connection off the big silver cylinder called the dryer off and jumping the connection. if your compressor comes on then you have low refrigerant that's when you hook up the cans of freon from the store to the low side of the system the fat hose the connector will only fit the low side. with the freon connected start the system and if the compressor does not come on you will have to jump that connection on the dryer to help suck in freon.

Remember to follow the directions on the package to refill the ac system.

Good Luck