it depends on the gas you are using. for ex\mple r134a and r22 you charge vapour through the low side and some gases are liquis charge only r404a r409 r407c and others these you charge carefully and slowly as liquid through the low side.
The low pressure side.
High side, If you charge liquid on the low side it can cause the valves of the compressor to break.
Low
Low side.Low side.
On the suction side, the low side...................
You add freon to the a/c by using the low side, suction side (larger hose).............
The low side line, pass. side.
to the low side
You add the refrigerant through the low side service port.
To the low side. Yes to the low side, on the suction side, larger hose on the a/c manifold behind the a/c compressor.
Add it to the low presser side. It will be located on the evaporator on the fire wall on the passenger side of vehicle.
No, the liquid (discharge) line is the high pressure side. The suction line is the low pressure side.