A/C high pressure gauge line exploded

I was stupid I'm going to say that upfront, I had no idea what I was doing but I went ahead and tried to do it anyway. I drive a 1994 Ford Ranger 4.0, 1994 uses R134a it is not an R12 conversion. When I bought the truck the A/C did not work and when I check the pressure it was at 0 PSI. I tried to recharge the system and see if that's all it was, I got the pressure up to the proper level on the first can of R134a which is odd since it was only a 12 oz can and the sticker says it takes 21 oz of refrigerant. I went inside to check the vents and it was still blowing hot air, went outside to check the pressure and now it was in the danger zone on the high pressure side so I went to go shut it off on both but the high pressure gauge line exploded and sprayed refrigerant in my face(I called poison control and they told me to sit down so I'm writing this. ) I disconnected the end of the line and the valve closed so that's okay. So here's my problems

1. The system reached proper PSI before the proper amount of refrigerant was added.

2. At the proper PSI with the clutch engaged the system was blowing hot air through the vents on Max A/C. Though it was slightly cooler than before.

3. When I decided to plug the relay back in (since I jumped 12 volts to the compressor clutch) the clutch was engaging erratically, it was engaging only when the low pressure side reached 70 PSI, and disengaged when it reach about 30 PSI.

Will someone who's smarter than me please tell me what's wrong with my system?

EDIT: I went back outside and turned the truck on, the A/C clutch is still acting the same weird way. I rechecked the pressure and both the high and low pressure lines were reading around 40 PSI with the truck off, there didn't seem to be any noticeable leakage that I could see in the gauge's. The clutch did engage for about a full minute and I did notice the air in the vents getting cooler. My battery light is on now, I don't have a code reader right now but I'll let you know the code when I can.

EDIT 2: I was still a little lightheaded from the refrigerant when I posted that edit... just wanted to let you all know that I do know that indicates a charging system issue.

If you getting real high head pressure you probably have a blockage in the expansion device. You cannot use system pressures to check refrigerant charge you must add the factory charge by weight. If you got water in the system the only way to remove it is to pull it in a deep vacuum the longer the better. Blast both coils with nitrogen to get the old oil and crap out that may be in there, clean/replace the orifice and accumulator and do a pressure test at 300psi with nitrogen for 45 minutes. soap test everything good and then evacuate it good. You may want to acid test the oil if any found just replace the compressor. Do your leak test before you open the system up you have both a leak and blockage in the system adding refrigerant is fruitless.

http://www.autozone.com/cooling-heating-and-climate-control/a-c-orifice-tube/santech-a-c-orifice-tube/ford/ranger-4wd/1994/6-cylinders-x-4-0l-mfi/167105_270314_0/
http://www.autozone.com/cooling-heating-and-climate-control/a-c-expansion-valve/compressor-works-a-c-expansion-valve/ford/ranger-4wd/1994/6-cylinders-x-4-0l-mfi/160937_5931_0/
http://www.autozone.com/cooling-heating-and-climate-control/a-c-accumulator/everco-a-c-accumulator/ford/ranger-4wd/1994/6-cylinders-x-4-0l-mfi/79118_0_0_2398/

Do you have the expansion valve? The bulb senser gets clamped to the low side coming out of the evaporator in the cab. Also if the system popped the high pressure relief it probably needs replaced as well after a couple times it just keeps leaking.

Good thing your facial skin is OK. That r134a oil feels very cold, eh?

I agree. Sounds like your orifice tube is plugged. It's a $2 plastic device. So the r134a isn't properly getting into the low-side, and the high-side is just pressurized more & more by the compressor, without any way to let that pressure go somewhere. For photos, see http://imgur.com/a/xMUKH

You'll need to replace the orifice tube, replace most/all of your O-rings (esp. at the compressor manifold), replace the accumulator, and then flush & evacuate your A/C system. Hopefully your compressor doesn't have "black death"? That's what plugs up the orifice tube. If so, time for new compressor & condenser, too.

http://www.aircondition.com/tech/questions/15/What-is-Black-Death

BTW, your high-side should be able to tolerate 450 psi. Why did your gauges explode? Was it even higher than that? Or just old rubber?

cvar said:

Good thing your facial skin is OK. That r134a oil feels very cold, eh?

Click to expand...

One of my mechanic friends asked me when I first started contemplating suicide when I told him about my attempt to recharge my system if that tells you anything.

Besides that I can confirm that I do not have black death, I pulled the compressor before recharging it to replace the oil and the oil I took out looked like the oil I was putting in.

Thanks for the help guys, I think when I get the time and money I'll send it to an A/C shop and have them evacuate it and pull a vacuum on it. I tested my alternator today and it's gonzo, it's only putting out 10 volts at any idle speed so I've got to replace that instead, that's going to take my budget for the A/C work . I'm thankful that I'm finally at the point with this truck where I can worry about the A/C instead of ball joints, burnt valves, exploding brake lines, ext... I think I'll fix my windows so they roll down instead of worrying about A/C right now