where is the air conditioning recharge valve located? I cannot find it

The "low" side is located on the compressor, drivers side-front, lower part of the engine.

It is usually on the drier or drier line. You could also remove the low pressure cut off switch and fill it from that point and then reinstall the switch.

turn left front wheel to the left, get under car in front of wheel just inside under car there's a flap remove it and you will see port. you may have to jack up car a little.