A/C Recharging?

[adamzan]

Yeah my old pathy (before the compressor wore out since I had it on 24/7 lol) used to get below 40 degrees even on the hottest days.

[JamesRich]

R12 was better at cooling. I replaced the evaporator, orifice tube and dryer on an 86 Lincoln town car once. Parked in the shop with the fan on low and recirculate I got 17F out the vents. Of course that's not how you properly test the system we just wanted to see how cold it would blow. When charging a system you should always have the blower on max and fresh air not recirculate. Some times I even leave a window open. If it gets too cold in the car while charging the system you will get false reading and end up over filling. Unless you’re using one of tungsten’s idiot proof "machines" that has a scale so you know exactly how much refrigerant left the supply bottle. Yes I have used one of those before and they are more trouble than they are worth.

With the orifice tube systems it's a fixed size port that lowers the pressure so when the blower is on recirculate the air keeps getting colder and the pressure keeps dropping until the compressor starts cycling. The expansion valve system that most imports and our pathfinders use is adjustable with temperature. When it reaches a preset temp the orifice starts to open and lower the pressure differential keeping it from getting too cold. The orifice tube systems will blow colder under the right conditions but the expansion valve systems usually blow cold faster and adjust to a wider range of conditions.

I enjoyed A/C work; it’s really a simple system once you learn it. Once you know how the system works it’s the same on any system even your house.

Yes tungsten read correctly you can use butane but who wants to ride around with a time bomb on their vehicle. The cooling from the system wouldn’t over ride the sweating from waiting for it to explode!

James