NewbernD

iTrader: (1)

The low pressure side shouldn't see more than 100 lbs working pressure. The high pressure side should max out around 200 psi or so.

You should think about brazing these lines back together instead of MIG'ing. If you can, maybe try to add a lug of aluminum to reinforce a bit.

DigDug

Can anybody explain why ES-12a should not be charged into a hard vacuum, while you can with the industrial stuff? Also, would I actually see a 5 degree difference using it?

katit

iTrader: (1)

Are you talkin about alternative refrigerants? because book says R134 should be 250-300 on high side and <50 on low. It's at 2000rpm. Mine is like 100/200 at idle.

rx slim

Okay, I'm back. . .and all my parts are in. I'll be pulling a vacuum and charging tomorrow on a system that has been disassembled and reassembled with a new drier. I'll take some pics and try to make a step-by step process possibly to be tacked. . .but I want to first make sure I've got all the details straight. Here's what I'm planning. . .

1. Pop the hood (just kidding) Connect the red manifold guage hose to the high side, the blue to the low side.

2. Start the car, turn the A/C on, open the high and low side guage valves to check the current system pressure.

3. Turn the car off. Connect the yellow hose to my vacuum pump. Turn on the pump until -29.5 lbs pressure is reached. Close the high and low side valves. . .let sit under pressure for 15-20 minutes.

4. Disconnect the yellow hose from the vacuum pump and connect the enviro safe can to the yellow hose. Purge the yellow hose and charge the system to just a bit above zero (car is not running).

5. Wait another 10 minutes. Purge the system with the car off. Open the high side valve, and charge one full can of ES. Close the high side, connect another can of ES to the yellow. . .open the high side again and charge to 30-35 lbs on the low side (I guess just close the charge can, and open the low side valve every now and then to check pressure as I go).

6. After 30-35 psi is reached on the low side. . .Close the both valves. Close the ES can valve, and disconnect it from the yellow hose. Turn on the car, start the AC, open both high and low side valves and check pressure. I should have around 250 on the high, and <50 on the low.

7. Close the valves, turn off the car, disconnect the hoses. . .and I should have cold air.

That seems to be the gist of it. I'm not too clear on when to have the car/ac running, but that looks right. Any input is great before I start tomorrow.

DigDug

You don't have to open the valves to read the pressures. In fact, always start with both valves closed before connecting the hoses to the service ports if there is any chance of pressure in the system. Not really an issue if you're starting with an empty system.


When deep vac is reached, close both valves first, then stop the vacuum pump.


DO NOT open the high-side valve when the compressor is running. Always charge into the low-side port. Also, ES recommends charging as a liquid (can inverted).

Charge to a little over zero with the car off, then bleed to zero as you mentioned. Then start the car and run the AC for at least 5 minutes to get temps and pressures stabilized. Then charge to full with the compressor running.

Just watch the pressures as you charge - low side should be 25-35, and high side 210-220 at around 80F ambient. ES says the high-side may read 15 or so lower than expected with R12. Ignore the sight glass as it isn't an accurate way to determine when it's full (even with R134a as I've found).

I just ordered the industrial I-12a, since you can apparently charge it directly into a hard vacuum according to ES. It's only a couple bucks more.

DigDug

One minor clarification after checking the pressures in the FSM - high-side pressure should be 207-213 PSI and low-side 22-28 PSI at 86-95F ambient. Also keep the engine running at 1500RPM while monitoring pressures. Using ES, the high-side pressure could be up to 15PSI lower than this, so just charge until the low-side pressure is right and high-side is within 15PSI of the prescribed range (say at least 195).

rx slim

Awesome info DigDug. . .thanks a lot. I'm glad you responded. . .for some reason I thought I was to charge the high side!

I also thought the valves had to be open to check pressures. . .that's really what was confusing me. Now it makes a lot more sense.

So really. . .the high side valve will never be touched. . .right?

Speed of light

iTrader: (8)

ES-12 can be charged into a hard vacuum; however, in some instances, dependent upon system volumetric capacity, the pressures yielded may suggest that the system is undercharged when it is not. This is only a problem if you are using low side system pressure to determine the correct charge. For a lot of reasons, it is best to predetermine and charge in the correct weight of refrigerant.

The "industrial" product has a different ratio of components and operates at a slightly higher pressure than ES-12. Interestingly enough, other manufacturers producing products (HR-12, HC-12, etc..) similar or identical to ES-12 recommend charging from a hard vac. Again, if you put the correct volume or weight of refrigerant in the system you will be okay. That will be 2 cans or 12 oz IIRC for an FD.

The "...5 degree colder..." is a reference to its boiling point. Using it in your system will not necessarily yield colder air--it's much more complicated than that. The refrigerant is regulated by an expansion valve that is designed to keep a certain amount of refrigerant in the evaporator at a certain temperature and pressure. It is augmented by a thermoswitch which is designed to prevent the evaporator from freezing up by cycling the compressor (and raising the low side pressure). These controls are what primarily determine how cold your air will be under any given set of conditions. If you bypass the evaporator's thermo switch, you will get colder air; however, if there is any humidity in the air, you will also freeze it up and air will cease to flow out of your a/c. It will produce a really cool fog out of the vents though... The short story here is that you want to mimic the characteristics of R12 as closely as possible in order that the TXV servo (expansion valve) functions correctly so as to keep the proper amount of refrigerant in the evaporator.

For those of you that have cars with COTS [cycling orfice tube systems] (non-FD) you can adjust the low side pressure cycling switch and pretty much make the evaporator operate at whatever temp you want. There is an important point here--low side pressure will ultimately determine just how cold your a/c will get. When you overcharge, the low side pressure will be too high and you will lose some of your system's cooling capacity.

I hope this answers your questions.

rx slim

I'm going to closely monitor pressures while charging, but one quick question SoL. . .my cans of ES-12 are 5 oz cans. Two cans would only yield 10 oz. Do you think I will be tapping into a third?

rx slim

Also. . .do I have to add any oil to the system after pulling a hard vacuum??

rx slim

Well. . .here's how things went. I added about 1/2 can of oil (2 oz) to the system before charging. Because I figured it couldn't hurt after pulling a vacuum on the system.

I added the es-12. . .just about two cans worth. . .but the low side pressure crept up way too quickly. I wasted some of the second can because I was at 50 psi, and it wouldn't come back down. By high side never got over 150. . .and my A/C is blowing cool at best.

I shut the car off, and am waiting for things to cool before I remove the guages, and while the engine is off, the low side is reading 100 psi, high side 150 psi. . .nothing is running.

Once it's cool I'm going to start it back up, turn on the air, check the guages again, and remove them.

Any ideas of what's going on???

katit

iTrader: (1)

Thant was unnecessary, you don't remove oil by vacuuming. Our system take 4oz of oil, so you added +50%

Did you idle it at 2000 rpm? Also, did you put cans into warm bucket of water while charging? Just make sure you don't "fluid-charge". Keep cans upright.

It indicates blockage at cooling unit. Either expansion valve clogged or it was frozen. Look at pressures after some time. They should equalize pretty quick after you shut car down.

rx slim

I was idling at 1500. . .pressures did come back down quickly. . .both are now at 115 with the car off.

I didn't know anything about the warm bucket. . .and now what do I do with the excess oil. . .is it a big deal??

I'm going to go start 'er up and see what the pressures do, and I'll be right back.

katit

iTrader: (1)

No blockage, it's good. Idle at 2000(FSM) and it's important to let system stabilize for a few minutes. 1500 is not enough for compressor to build proper pressure. If you have aftermarket underdrive pulleys - RPM's will need to be even higher.

Warm water will speed up your charging process. System takes freon very slow when you get up to 50%, placing can into warm water will help a lot.

Excess oil is not good. I guess it won't damage system (this amount) but it will degrade performance.

rx slim

Okay, running the A/C again low side is about 50, high side about 160. Air blows cool, but definitely not cold.

Pressures come back to 110 fairly quickly after shutting the car off.

katit

iTrader: (1)

Set proper RPM's. Observe for 2-3 minutes. Then add freon until you get to spec pressures.

rx slim

I'll have to observe for a few days, I'm all out of es-12. I'll place an order and get back to it in a few days. It will at least let me monitor it for a few days. Thanks for your help. . .I'll let you know in a few days.

katit

iTrader: (1)

Btw, your compressor probably cycles right now when idling..

DigDug

Thanks for the detailed response, I really appreciate your help.

I've measured/weighed the amount of refrigerant charge when using R134a, since I have the factory specs for how much the system holds, but I'm not sure with the ES stuff. If their conversion ratio of .33 is correct, and the system holds 21oz of R12, that would come to 7oz of ES-12a.

Did yours work at the right pressures with 12oz? Which system does your car have? Mine is a 93, originally ran R12 but was converted to 134a. With 134a, I used 18oz per the FSM and got close to the right pressures.

One last thing, I ordered the industrial stuff - does this have the same conversion ratio as ES-12a? Also, you mentioned that it has a higher operating pressure, do you know how much higher it would be?

Speed of light

iTrader: (8)

I looked at the FSM and I think that there may be a typo. Most automotive systems hold about 2# and the FD is no exception. Mine is a '93 base (originally R-12) and the sticker on the hood says it uses 1lb.-12oz. (or 28 oz. of refrigerant), which is about what I would expect.

If you put 2 cans (5 or 6oz sizes) of ES or I-12 refrigerant in you will be fine. Do not charge in more than that or you will reduce system performance. I-12 will want to have a slightly high ratio of charge (.35--.4) based on my experience. You can get the difference in pressures from the pressure/temperature charts, but it's no big deal--just a few pounds. I-12a still runs around 10% lower high side than R-12 for a given set of conditions, any advantage comes from it's ability to run at a slightly higher low side pressure.

No need to make this too complicated. Just make sure you are properly evacuated (most important) and charge in 2 cans. It will be fine.

ikpfal

iTrader: (3)

Can some one tell me or point me in the right direction on where and what needs to be oiled. I pulled the entire A/C system from the car 93 touring with the denso system. I am changing everything except the hard lines to include the compressor, dryer, expansion valve, condensor, and evaporator, and using es-12. What is the best oil and refridgent combo to use.

M104-AMG

iTrader: (8)

The industrial ES-12 states on the can to dispense with the can upside down, which means you're introducing it into the LOW side as a liquid.

Can someone please confirm that ?

BTW: I'm going to SLOWLY introduced it with about a 25inHg of vaccuum.

Please correct me if I'm wrong.

:-) neil

katit

iTrader: (1)

Don't do that. I mean, professionals do that, but you can damage compressor by charging with fluid. Manual says gas charge only. Use warm bucket of water to speed it up.

Speed of light

iTrader: (8)

Neil, it is confirmed--You can and should charge it in as a liquid. (So if you are using a top type can tap, then you need to invert the can.) Just go slowly and it will flash into vapor before it gets into the compressor. I have never slugged a compressor with this stuff; it does behave differently than Freon.

Because this is a blended refrigerant, with a high and low pressure components, it is necessary to charge it as a liquid to prevent it from fracturing (causing the components to separate by vapor pressure). Failing to charge as a liquid can prevent the lower pressure component (R600a) from charging into the system at all.

M104-AMG

iTrader: (8)

Thanks.

Have you had any experience replacing a home A/C unit's refrigerant with their ES-22a ?

http://autorefrigerants.com/22a.htm

Thanks,
:-) neil