A/C refilling, am I doing something wrong?
I borrowed a vacuum pump that I ran for 15hrs. I turned it off and 3 hrs later the needles didn't move so everything was tight and leak free. Before I did this I poured 4oz of the 150 oil into the accumulator since the service manual says if you replace the condenser you need to add 2oz and another 2oz for the accumulator.
Now I added a 12oz can without the car running then a 3oz can that contained 1oz of oil, 1oz of freon and another 1oz of some special crap I don't remember. I filled this through the low pressure side. I then started the car with the AC to max and on recirc. The low and high sides are the same pressure 30 psi (verified the ac clutch was engaged too). So I dumped another 12oz can which brought the total up to 25oz of freon. So I bought another 12 oz can and dumped maybe half and now the low side with the AC on was around 70 psi as was the high side. The low side isn't cold and the hot side isn't hot and same goes for the condenser being not hot and I had the AC on for about 15 mins. I slowly dumped the freon out so the low side was between 30-35 psi and the low side line never got cold. Even when I was dumping the freon to start with the low side never got cold but the system was under a good vacuum when I began adding the freon.
1.75 lbs is around 28oz of freon right? Sorry for the long read. It says the high side should be between 150-200 but it never got that high.
Is the AC compressor just screwed or did I do something wrong during the filling process?
Last edited by danieloneil01; Sep 24, 2014 at 10:14 PM.
I borrowed a vacuum pump that I ran for 15hrs. I turned it off and 3 hrs later the needles didn't move so everything was tight and leak free. Before I did this I poured 4oz of the 150 oil into the accumulator since the service manual says if you replace the condenser you need to add 2oz and another 2oz for the accumulator.
Now I added a 12oz can without the car running then a 3oz can that contained 1oz of oil, 1oz of freon and another 1oz of some special crap I don't remember. I filled this through the low pressure side. I then started the car with the AC to max and on recirc. The low and high sides are the same pressure 30 psi (verified the ac clutch was engaged too). So I dumped another 12oz can which brought the total up to 25oz of freon. So I bought another 12 oz can and dumped maybe half and now the low side with the AC on was around 70 psi as was the high side. The low side isn't cold and the hot side isn't hot and same goes for the condenser being not hot and I had the AC on for about 15 mins. I slowly dumped the freon out so the low side was between 30-35 psi and the low side line never got cold. Even when I was dumping the freon to start with the low side never got cold but the system was under a good vacuum when I began adding the freon.
1.75 lbs is around 28oz of freon right? Sorry for the long read. It says the high side should be between 150-200 but it never got that high.
Is the AC compressor just screwed or did I do something wrong during the filling process?
Were high and low side same pressures at all times basically? If so, compressor isn't on (or isn't working at least). Usually as soon as it clicks on when you're adding refrigerant the high side shoots up and low side goes down pretty quick..
How are you sure the compressor is on?
Do the pressures ever move opposite directions? i.e. high goes up and low goes down? or always the same?





You SHOULD see equal pressure on the HIGH & LOW sides when the system is idle and the pressures should go active (high on the high side and around 28-30 psi on the LOW side when the compressor is connected and driving the compressor..
If,,, you have the correct differential pressure between the high and low side and the orface restrictor is spraying R-134,,, you should have cooling, The LOW side should be COLD and the high side should be HOT.
Sounds like you charged it ok.. Did you have the R-134 Can UP-RIGH during the low pressure side FILL. Up-Right injects GAS in the gas side..
Bill
I guess I'll check it out when I wake up in the afternoon and just make sure the ac clutch is engaged the whole time and verify the pressures when it's on and off and report back.
Last edited by danieloneil01; Sep 24, 2014 at 11:21 PM.





Bill
Thanks Bill. Time to go yank it out.
Last edited by danieloneil01; Sep 25, 2014 at 12:52 AM.
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Is 28oz what the system actually holds if it's completely empty and under a high vacuum?
Do you add it on the low side or does it not matter?
Should I start the car and have the AC enabled then add the first can?
I just turned it off and it has -30 in it so I'll see if it holds.
Last edited by danieloneil01; Sep 25, 2014 at 12:36 PM.
Once you start adding refrigerant you should start building high side pressure and should see a pressure diff between low and high. Around a hundred or so pounds. IF your compressor is running. If it's running and you're gauge pressures are equal. I'd suspect bad compressor valves. Make sure the compressor clutch is engaged for sure.
On second thought the orings came with the drier for both connections. I only replaced the 2 oring connections to the condenser and orifice tube. Hmm
Last edited by danieloneil01; Sep 25, 2014 at 01:50 PM.
I just turned it off and it has -30 in it so I'll see if it holds.
It almost sounds like the orifice tube isn't sealed or something and instead of being the "dividing line" between high/low pressure areas, it's just letting everything through
Hard to say without seeing it though. AC systems can be finicky. You should def. see the high side pressure go up quick though once the compressor comes on
You can turn both of the ***** on the gauges all the way closed and the gauges will still be connected to their respective hoses. The ***** are a block off between the high/low side hoses and the center "fill" hose (for lack of a better term)
it took me a little while to figure that out.. I always thought you had to open the ***** before the gauges would work but that isn't the case.
If you had both the high and low side ***** wide open on the gauges themselves, then yeah, that would explain a few things, lol
Last edited by danieloneil01; Sep 25, 2014 at 03:59 PM.








