Thread: AC Gurus - Problems After Refill

Mine used to do this too. Then it would only work if I taped on top of the relay. This winter it mysteriously kicked in, but when I tried to get it to work when it got warmer, no bueno..

Odly enough it's working semi fine today. I'm guessing it could be debris inside. Guess a flush and a redo should do the trick. My old P11 had AC that was sooo cold, unless OEM R134a just works that much better, I don't see why this one can't.

Like I said above replace the drier they are less than $20 for the b14 not sure about p11, once they absorb so much moisture they tend to clog up, how long was your system open for?

Are using Freon or R-134a? Freon is R-12.



It's one of the refrigerants in line to replace R-134a in the near future. At this moment, I don't recall it's advantages and disadvantages, but I will check my notes later.

Try this for diagnosing:

Turn AC on full blast with car running. See if clutch starts to cycle.
If clutch cycles, check to see if it cycles quickly. Off, then on again. The compressor should stay on for about 30 seconds. If it cycles more frequently than 2 times every 15 seconds, it is probably underfilled.

If clutch doesn't like to cycle in hot weather, try spraying the condenser down with water. This helps to improve the efficiency of the condenser and get liquid refrigerant made. If this seems to improve cycling, then the system is too low still.

A standard P11 takes 24-28 ounces of regrigerant, and you wanna use 3.5 ounces of oil for every pound. So 6.75 ounces should do it.

Remember, your AC system pressure will show high on the "low" side when the clutch is not cycling. Pressures within the system will stabilize when the cycling stops, and you can see over 100psi on the low side. You have to check pressures when the clutch starts to cycle.

Lastly, each small can of regrigerant only holds about 10oz of regrigerant, and 1oz of oil. You will need a few of the small cans to get a full charge from it.

Also keep in mind that higher ambient temps will produce slightly higher pressure readings.

Hope this helps!

Will take a look . As far as I know at least since January. I'm sure since the guy got into the front end collision. The AC condenser was pretty bent.



Freon is R-12, but its just like using "Xerox", "Google", etc.

Here is a good read: Future Alternative Refrigerants

R152a sounds great, except for it's combustible, and poisonous when burns. This is why CO2 is also being considered. Problem with CO2 is, it requires to be at over 1k psi, which would put a great amount of stress on the lines.





It would kick on, work for about 5 seconds then kick off. When I would bleed the low pressure side only air would come out. I would bleed it until green liquid would come out (R134a), at that point the compressor would kick on.

It ran for a while until it stood all day in semi warm parking garage and then driving in the hot 104*F weather. It stood all day in the parking garage and today it is working just fine. Weird thing

If you are seeing liquid, it most likely isn't refrigerant, but the oil residue that mixes with it. Regrigerant boils off at below freezing temps. -15*F to be exact. So you won't likely see it as a liquid. By the time it hits atmospheric pressures and temps, it will be vaporized.

If the compressor is cycling for only 5 seconds, it is underfilled. If you overfill the system, you will lose performance drastically. My experiments show that slightly underfilled (full, but on low end) will outperform in most all situations. I highly doubt you overfilled the system on only 2 cans. If it performs better in the cool weather, it likely needs more added.

I was actually just asking if you were putting in R-134a or Freon, since Freon is a brand name for R-12. I hadn't actually realized they branded their other refrigerants under the same name.

As for the article, I agree with most of it, but I think the best replacement for R-134a is still debatable. The one suggested (HFO-1234yf) seems to have potential if the claims they made are true.



I dug up my paper on the subject (I wrote it last fall). Here is the section regarding R-152a. It is more environmentally friendly and exhibits better performance, but is flammable and less miscible. Because of the latter, it seems unlikely that it will take the place of R-134a in automobiles, but will become more common in general industry, where safety can be better regulated.



Pure hydrocarbon refrigerants (HC's as opposed to HFC, CFC, HCFC, etc.) are best for the environment (like propane), but pose obvious safety dangers to humans. Particularly in systems with pressures lower than the ambient air, there is a danger of oxygen leaking in and mixing with the refrigerant creating a highly explosive mixture. If that safety issue can be overcome, R-134a will most likely be replaced by a hydrocarbon refrigerant (at least as another intermediate). R-134a was never meant to be a permanent replacement for Freon.

As for CO2, you're right about high pressure systems. It also seems an unlikely solution if you consider the carbon footprint planning view of the future.

Oh, it looks like I got a little carried away there.

I think I'm going to give ES-12a a go. It's fairly cheap and seems to be fairly efficient. Thought it is flammable, so is R-152a and R-134a is. The difference is R-152a and R-134a both give off deadly gasses when burned.

How efficient is ENVIRO-SAFE

Only downfall is VA prohibits flammable refrigerants. But from what I'm seeing R134a is flammable too.

One guy using actual propane.
http://www.peachparts.com/shopforum/showthread.php?t=254928

when i took my car to the shop they did a vacuum and fill for $45, id call around and see what you find