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Discussion Starter #1
Hi!
Clutch is engaging and disengaging... I just replaced every component in my a/c system ( comp, cond, evap, hoses and sensors and my **** is messed up.
I service low and high side with correct Freon a mint and low side goes to like 70 and high rises to like 450 and I get scared and shut it off.
condenser not getting hot, drier isn’t getting cold. I cleaned the orifice tube out and noticed a few metal shavings but not bad like what you see online....

moral of my spiel is I service it and I’m basically getting an over pressure in my low side when I service with correct amount, and my high side goes through the roof.

At work I have a robinair servicing cart (use on helicopters) so I know I’m adding the correct amount of Freon.
I add 28 oz (1lb 12 oz) 6 oz of oil for my first charge of the system.

thoughts? Ideas? Maybe it’s compressor? Or filter drier is toast?
 

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I'm jealous--it must nice to have access to that AC cart. Oooowee, I'd be afraid of 450 psi, too.

Cycling on-and-off rapidly can indicate a bad high pressure switch. On the other hand, you actually have very high pressure on the high side, so that sounds like a clog, either orifice tube or accumulator (drier). It sounds like you re-used the old accumulator (drier) and the orifice tube--both have been replaced. A variable orifice tube works better than the basic version and doesn't cost much more. Plus, any crap that got past the orifice tube could have ended up in the old accumulator.

Adding a new cycling switch (the one on the drier) and high pressure switch (compressor to condensor) will take away those uncertainties, too

I don't have a FSM nearby so I'm not certain of the oil capacity (you said 6, but is it 8, or are you counting a couple of ounces in the new compressor. You're spot on with the 28 oz refrigerant. (assuming it's an R-134 car, not actual Freon.)

Since you ran the system without replacing the orifice tube and drier, get out all oil (including the compressor) and flush everything before re-assembly. Yes, it is a pain. Then you can measure the total oil required and add the proper ounces to each component. Then you'll know the whole system is super clean inside and you'll start off with oil everywhere it should be.
 

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I'd suck the system out and try blowing some nitrogen through the condenser. It may be clogged. They're not terribly expensive (or difficult) to replace.
 

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Cycling on-and-off rapidly can indicate a bad high pressure switch.
Adding a new cycling switch (the one on the drier) and high pressure switch (compressor to condensor) will take away those uncertainties, too
On these cars there is a high pressure sensor not a switch. I think it can be read from a live data scanner. It will set a scan code without turning on the MIL lamp.
I don't have a FSM nearby so I'm not certain of the oil capacity (you said 6, but is it 8, or are you counting a couple of ounces in the new compressor.
I do not work on A/C but the FSM says that the old compressor oil in the case should be drained and measured. It then suggests one drains the new compressor and a equivalent amount added. It warns that a new compressor may be shipped with 8oz

The FSM shows these oil amounts:
Condenser 1oz
Evaporator 3oz
Accumulator 3.5oz

Robtunez did you add 6oz to the system without checking the amount already in the new compressor? If so you may have way to much oil.
 

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Discussion Starter #6
Have yet to take the system back apart. The cycling switch and the high pressure sensor are brand new so I highly doubt it’s those. I think I need to disconnect everything and try blowing some air threw all components to see if there’s a blockage. That’s the last thing I can try and trouble shoot.
 

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I was having the same thing happen, after getting pretty much everything replaced by a shop with parts I bought off Rock Auto. Enlisting the help of a colleague after the shop threw their hands in the air, my colleague noted that the 2 lines going into the condenser were switched. The line with the sensor on it should be on the upper port into the condenser - per the factory manual. I've been enjoying the best A/C my wagon has ever had for the past week and a half even though fall is definitely making it known it is on the way here in the South. Just throwing this out there.
 
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