Could someone tell me how to distingush which line on the A/C is the low presure line? I bought a refill kit and have to test it first using the low presure line.
This is on a 1999 1500 Ram Sport with the 5.2 engine.

Thanks for your help.

 

I have an 01 5.9 and the lower line is under the intake tube. I have an aftermarket intake so it was pretty easy to get to.

 

I know on my 96 1500 it's on the passenger side. The low side recharge port is on the passenger side near the radiator.

 

Both mine are on the passenger side. One in front by radiator and the other in back by firewall. The one in front has a cap with a "H" on it and the one in the rear has a cap with a "L" on it. Now one would think that would be pretty plain.

But what if for some strange reason someone changed these caps around. I just don't wanna hook the gauge up to the wrong line. Could be exciting.

The back line "L" goes into what I'd call the evaporater. The front line "H" goes through the firewall.

Any Suggestions?

 

My low side goes into my evaporator so I would assume your low side going into the evap would be correct. It's just in a different location than mine.

 

The high and low pressure fittings are different sizes. Low is smaller.

 

Both fittings are the same size on mine. I went ahead and tested using the one by the evapator. But now I have another problem. I attached the hose and read the gauge then removed the hose now it is leaking where I attached the hose. like something inside the value is stuck. I reattached the hose and pulled it off again. Still leaks tapped on the value with a screw driver it still leaks. put the cap on as tight as I dare. Anybody had this happen to them? What should I do now that I can't get it to stop leaking at the input "Low Pressure" value????????

 

trie unpluging it wile presser is high like when its running i had that problem
your low side comes from the evap in the fire wall going to the condencer
high side comes from compresser goes to evap