That depends on the refrigerant type and ambient air temperature.
Freon is added through the low side ac port. A gauge is recommended to check the Freon pressure, as too low or too high pressure can cause the ac not to work properly.
Freon goes into the low pressure side of the air conditioning system. The attachment from the gauge used to put the freon in will only attach to the low pressure valve so it would be pretty hard to do it incorrectly.
The Freon is added through the low side ac port. Using the proper type of Freon and a gauge, fill the system to the recommended pressure.
R134a goes into the low pressure port
Always to the low pressure side. The low pressure side fitting is normally near the dryer ( large silver canister).
On the low pressure side. A charging hose will only fir on the low pressure side of the AC system.
The schrader valve on the low pressure side of the system.
The Freon is added through the low side ac port. Using a gauge and the proper type Freon, fill the system to the recommended pressure. Too low or too high Freon pressure will result in the system not operating properly.
Low pressure side-- larger hose from compressor
Through the schrader valve on the low pressure side.
You don't add Freon as it has R134a not Freon. You add it to the low pressure side which is the larger hose.
When you go to put freon in, first check to make sure that there are no leaks. Take off the cap on the Low Pressure Side port. Make sure that you have the right kind of freon, and then place it inside the Low Pressure Side, paying attention to the instructions on the kit.