UnderCover89TBI

iTrader: (25)

wow this is very interesting. I have a R134a machine and r-12 machine. seeing this stuff and what my car does really makes me wanna switch. I have customers ask about this then I talk to the a/c tech and we cant really do anything with it because legally we have to recover and dispose of as laws. where the home person can really do as they please. very intersting topic here guys.

92GTA

iTrader: (11)

I hit a low of 20.7F today with my fan on the lowest speed out of my center/top vent. BRRRRRRRRR! The cold almost made me feel sick haha

Reid Fleming

iTrader: (2)

I think it's time to adjust the low pressure cycle switch up a bit.

20° is just wasting gas.

92GTA

iTrader: (11)

But man will it feel bitching on bi-lev with the fan on high in the summer when it's 115 outside

UnderCover89TBI

iTrader: (25)

wow yeah it does sound like that is a little overkill. you'd think about 35 degress is about as low as you'd want it to go. But that's just me! haha. sweet

chazman

iTrader: (4)

Is Autofrost similar or the same as Duracool?

Reid Fleming

iTrader: (2)

Autofrost is an HCFC. Duracool is an HC.

(R-12 is a CFC, R-134a is an HFC)


CFC = chlorofluorocarbon....the stuff which is supposed to be bad for the ozone layer.

HCFC = CFC with a hydrogen atom (the hydrogen holds it down at ground level, breaks down before it gets into the ozone layer). Supposed to be about 5% as bad as CFC's when it comes to the environment.

HFC = hydro-fluorocarbon.....No chlorine. R-134a is the most well known one of these. Also good ozone wise, but bad in terms of global warming potential.

HC = Hydrocarbon.....Typically propane based refrigerants like Duracool. No ozone or global warming issues. This is why you're allowed to vent your BBQ into the air when you use it.

HC refrigerants have high performance because they use propane (or R-290 if you prefer propane's official name). Autofrost has high performance because it uses R-22. The same stuff that is used in residential air conditioners. R-22 and propane have very similar temp-pressure curves. Much better performance than R-12 or R-134a.

The duct temps vs comfort really depends on what the ambient is doing. On my drive to work at 4:30AM, just running it on NORM at the slowest fan speed is cold. Hence why I run it on such a minimal setting. On the drive home in the afternoon sunlight with 90°+ outdoor temps, 35° feels good. Lower temps feel better though. I typically run MAX with the 2nd slowest fan speed.

chazman

iTrader: (4)

I've heard of people topping off their R12 with Duracool for years without issues. Any thoughts on that?

Reid Fleming

iTrader: (2)

Shouldn't be a problem. The HC refrigerants out there have no issues with the oil used in R-12 systems. And the HC refrigerants are blended to somewhat match the temp-pressures of R-12 anyways. In other words, it's not 100% propane in Duracool. It's probably something like 50% and some mixture of Isobutane (R-600a) and Butane (R-600). Possibly a few other things.

Fast355

iTrader: (2)

The Sentra is 50% 290 and 50% R-600a, you can get R-600a in small cans from Home Depot/Lowes/Walmart to refill butane lighters.

*84TA

Looking into Autofrost for my car. What is everyone's thought replacing the rubber hoses? They look to be in good condition. Car is an 84 (compressor on drivers side) From what I have read, these may not be Barrier-Type hoses. If I should replace them, where the heck do I find them? I have not had luck locating them.

Reid Fleming

iTrader: (2)

Well this last week has been a non stop week of heat here in Houston. I thought I'd test out the performance on the drive home from work.

102°F ambient temperature
37% humidity
76°F dew point
111°F heat index

(The record hottest day of all time in Houston is 109°.)

I managed to get 34° duct temps on city streets (35-40 mph) and 35° on the highway (75 mph). Needless to say, it felt really good.

I tried touching the driver side window, but couldn't keep my fingers on it. It would burn me if I tried.

built

very good reading.

If I get my license and want to do some at home jobs for friends and family how can I find out the proper procedures and where can I buy the vacuum machine etc to do the job.

What were the answers to this guys questions , they were good questions that I would like to know also.

Reid--
I got my license and am looking to get my cans of autofrost ordered here this week, but was wondering a few things:

1. Did you remove your Schrader valve as is recommended in the Autofrost instructions? They say the adapters come with a new Schrader valve, and that it works better if you remove the old one.

2. Do you need any special connections to the Autofrost adapters? Those handles you mentioned from the guy on e-bay look a lot nicer than the ones on the Autofrost site, but do those hoses connect directly to the Autofrost adapters?

3. On the old R-12 manifolds, there are two pressure gauges; a high side and low side, I believe. Is it sufficient while charging to have only one gauge, on the low (fill) side?

3.1EyeCandy

iTrader: (3)

Whenever I get my GTA back on the road, you're gonna have to lend me a hand with the autofrost setup Reid. I'll have all new A/C parts and a sanderson style compressor meant for R12 with the LS1

Reid Fleming

iTrader: (2)

Sure. Good A/C is always fun to get working right. Besides, I'm a sucker for a clean looking GTA.

I bought my vacuum pump on Ebay. I bought a Yellow Jacket 6 cfm model.
http://www.yellowjacket.com/node/681
It's overkill for the do it yourselfer. But I wanted a good one just because I like nice tools. It's got an oversized oil tank, pressure gauge built in, oversized heat sink. Two stage motor, gas ballast. A few other nice things too (large threaded plugs that seal well and are hard to strip, etc)

1) Removing the schrader valve on the accumulator is optional. It really depends on if you want to use the blue special Autofrost adapters....... You get 2 pieces and a cover with the blue Autofrost adapters. One of them screws over the 1/4" accumulator port. And then the other one is a 1/4" blue piece that screws over top of that. So the end result is that you have a 1/4" blue port to connect to your hose just as you would had you used the stock 1/4" accumulator port without the special adapters.

Reading the above may sound confusing, but if you see the actual pieces themselves, you'll see in about 5 seconds how they connect to the system.

Removing the schrader valve on the accumulator will speed up vacuuming and charging. Because your schrader valve would be on the outer most blue pieces (both Autofrost blue pieces have schrader valves)......On the other hand, if one of your schrader valves ever got a leak, you would have the other ones to keep the system sealed up. Now replacing a leaky schrader valve is no big deal. It's about $4 in parts. And if you have one of those tools that allows you to change valves without losing a charge (I do), then it's even simpler.

I left mine in, because time isn't that important to me. If I were working at an A/C shop and doing multiple cars a day, I would remove the schrader valves during service and put new ones in afterwords.

2) No special tools needed. The can tap screws on to the blue 1/4" adapter or the 1/4" accumulator.

3) For the most part, a single gauge with low side pressure only will do. But make sure it's an actual psi guage and not one of those cheap "red/yellow/green" zone type of gauges. I still like having a real manifold gauge with both low and high side gauges on it. It's handy for seeing how warm your condenser is. At what psi the passenger fan turns on/off. And in general how the system is running.

Being able to vacuum the system through both the low and high sides speeds vacuum time. And charging the 1st can through the high side helps move the oil through the system without slamming the compressor with liquid refrigerant. But that's with the engine off only. In general I recommend charging only through the low side due to safety reasons. In other words don't charge through the high side unless you know exactly what you're doing and why.

92GTA

iTrader: (11)

Just to let everyone know, I bought this summers supply of AutoFrost for some other auto projects I have from http://www.refrigerantsales.com/shop...ndex&cPath=1_8

Enjoy!

Alex

Fast355

iTrader: (2)

Since this post popped back up, might as well post that I just switched my 2012 Titan over to a 50/50 mix of HC on the first warm day here. Look at the back window after an hour or so of driving around town on a humid 85*F day.

Justin89Formy

iTrader: (26)

Just had my car converted today. As far as I can tell, its cold. I'll wait for the heat and humidity before I judge

actarnoff

iTrader: (1)

How much did that conversion run you?

92GTA

iTrader: (11)

Well I need to buy some more R-406a and I can't find it in the small cans any where. Any idea where to get it now guys?

Alex