techno_1961

so i have a 86 iroc with a 305 tpi i need to recharge my ac to see if it works. all we have around here that i aee is r134a do i gotta use somthing else.

91_RS_maro

R12

BlackMamba

iTrader: (6)

I will use also R-12.
Someone told me that if you use R-134a it will destroy the inside of the lines and also the compressor itself. That's is why I am useing R-12

Gregzz4

If your only option around your neighborhood is R134a, then go ahead and use it, but make sure it is retrofit properly
It won't hurt your system if everything is done right and all your parts were in good shape to start with
A retrofit involves things such as flushing the old oil out and installing new O-rings and fittings
R12 is generally a colder running system but R134a is more Enviro-Friendly
You'll be OK either way as long as it's done right

KNBlazer

x2 .. make sure you flush your system as Gregzz4 stated.. or you can go to mexico and buy R12...

91_RS_maro

i think you can still buy r12, you just need a license

sonjaab

If any A/C places have any r-12 left they are gonna charge mega bucks per lb. to recharge your system with it.
Many places now use a r-12 substitute that is available under several brand names like Hot-shot or even this:
http://www.freeze-12.com/

Or you could go the r-134 conversion route which is quite $pendy but necessary if you live in the south or out west and like to ride in comfort!

My 84 came from NC and the previous owner had the r-134 conversion done and the AC sucks and don't cool the car worth
a darn!

58mark

iTrader: (3)

I'm redoing my system with Freeze12 in the next week. I just put on a new compressor, dryer and orifice tube yesterday, and I'm taking it to a garage to have it eacuated and charged.

The car had signs that at one point somebody half-***ed a nto 134, so I have to have the lines flushed before I go to the freeze12


I'll post how it works, I've heard nothing but bad things about the effectivness of 134 in our cars, especialy for a dark car in TEXAS (like mine)

DJP87Z28

R12 is history and the old A/C systems using it are too. Convert to R13A or you will have no A/C. And those other substitutes are just stopgaps by fly by night companies.

kevmann

Thats great 58mark. I would love to know how that works.

58mark

iTrader: (3)

i've had freeze 12 in my crown vic for at least 4 years now, and it works great. if thats a stopgap, bring it on.

fact is some cars dont work well with 134, the camaros being one of them. I'm looking forward to trying the freeze12 in my car and posting the results

Reid Fleming

iTrader: (2)

Freeze12 in Texas? Ugh.

Freeze12 is 80% R-134a and 20% R-142b.....R-142b is a warmer refrigerant than R-134a is. I wouldn't worry about flushing the lines unless the compressor gave out.

If you're going to stick with R-134a, then you should go with a Smart VOV and a better condenser.

58mark

iTrader: (3)

like I said, I've had a freeze12 car in texas in four years now... no complaints

Reid Fleming

iTrader: (2)

Let us know the results. Grab some duct temperatures preferably.

What year is your Crown Victoria?

sonjaab

No matter what refrigerant or sub the AC shop is gonna use for best results
they should evacuate your AC system THEN charge with the new refrigerant.

58mark

iTrader: (3)

it's an 86

JamesC

iTrader: (5)

My IROC cooled so poorly with 134 that I actually returned to 12.

JamesC

58mark

iTrader: (3)

you certainly can't do it the other way around...

91_5.7_TPI

iTrader: (2)

I stuck with R12 until last summer. I had my car retrofitted to R134, and the compressor was about a year old at the time. I was worried about the coolness of the AC after the conversion, but I checked it and it was less than 55 degrees, I think less than 50. So, I'm happy with the results. It's still cold this year, which is the second year I've started the summer with AC in the 6 years I've had the car. Something always manages to go bad in the winter leaving me with the need to repair/replace with no money to do it for the first half of the summer haha

Rayzor32

iTrader: (1)

Theres a lot of misinformation here.

THE ONLY 2 Refrigerants GM recommends are R-12 and R-134a in their a/c systems. GM does not recommend any flushing agents of any kind. Also it is illegal to vent any refrigerant into the atmosphere. No shop will service your a/c if you fill it with anything other than r12 or r134a, the refrigerant has to be reclaimed and it will contaminate their equipment.

Your best bet is to retrofit. Lets face it R12 is EXPENSIVE. By now your accumulator needs to be changed anyway and if your system has a leak and you fill it with R12 and it all leaks out well then you just wasted all that money. To do this properly with R12 put the system under a vacuum and see if it holds, if it does then charge it with 1/2lb and some dye and run it to circulate the dye and see if you find any leaks. If no leaks are found recover the refrigerant and change the accumulator and recharge it.

It would be easier to retorfit, you have to change the accumulator anyway since its so old and the system is empty. GM doesn't recommend any flushing, just drain the compressor oil and change the accumulator and fittings and refill with r134a and the proper PAG oil for your compressor.



Here's where the whole "r134a" sucks BS comes in, THESE systems were designed for R12, R12 and R134a have different pressure temperature relationships. The pressure switch on the accumulator is calibrated for R12, fortunately on these cars it is ADJUSTABLE! You can make snow come out of your vents with r134a if you wanted to! But then your evaporator would ice over. Don't believe me, you can try it yourself, it has to be a humid day to work, close all the doors and windows and jumper the pressure cylcing switch, ive gotten the vent temperature down to as low as 28*F.

The pressure switch tells the compressor to shutoff, lets just say it shuts it off at 32psi and at 32psi the temperature of R12 is 32*F (lets say) and you convert it to R134a and it shuts it off at 32psi but the temp of r134a at 32psi is 34*F, now you have to go and adjust that switch to shut it off at at a lower pressure. The goal is to keep the evaporator as close to 32*F as possible, colder than that and it will ice over.

DirtDawg57

iTrader: (3)

How do you adjust the pressure switch?

Rayzor32

iTrader: (1)

There is a flathead screw on it, you adjust it until you get the low side pressure you want.

Reid Fleming

iTrader: (2)

Let's be honest though. In Buffalo, your summers are going to be short and somewhat mild compared to the deep south, southwest etc. R-134a in Phoenix, Houston, Miami in our cars isn't going to work good unless some serious changes occur.

R-12 is $30/can. An empty system would take 3 cans. This isn't THAT expensive. The issues with R-12 prices going up has fallen by the way side, now that many old cars have either been destroyed/crushed/whatever or converted to R-134a by now. There isn't as much demand for R-12 as we think there is.

Our cars have old small condensers. This was fine for R-12. Newer cars have larger condensers and better condensers. Anybody who has looked at transmission coolers knows how bad tube and fin coolers work and how good stacked plate coolers work.....Our condensers are essentially tube and fin. Newer parallel flow condensers are essentially a stacked plate design. Look at houses today compared to 20 year old houses. The condensers outside in the back yard are 4 feet tall. The older homes have condensers the size of a rolled up sleeping bag.....The reason better condensers exist in the automotive world is because of the poor cooling that early R-134a cars exhibited.

To get 28° air coming out of the ducts with R-134a, you'd have to have the system running somewhere between 15-18 psi. (see picture below) Now how the heck are you going to get the system down to 15-18 psi during 100° weather outside? Or in traffic? The critical temp of R-134a will make it cease to function if you get stuck in traffic and the radiator/condenser are too hot. 28° with the low cycle switch jumped when it's 60° outside is easy enough to do. But not so easy during hot humid weather. Most of the time a vehicle in south Texas will not cycle at all during the summer months.



Now I do agree that if you have an R-12 (or any other refrigerant for that matter), you really do need to get any leaks fixed. And R-134a (putting aside the conversion/oils issues) can cool good with a parallel flow condenser, smart VOV, and lower psi cycle point. But it's still not going to work as well as R-12, HC based blend, and a few of the other alternatives out there.


Look at the rubber plug on the passenger side of the accumulator. It has two prings. Once you unplug it, there is a tiny screw inside. 1/4 turn to the left will lower the psi shut off point by 4 psi.

Rayzor32

iTrader: (1)

I'll agree R12 is the better refrigerant but its always a cost issue.

travis401

iTrader: (1)

I bought some cans of freeze 12 about a year ago, and even in the heat of texas, it was bone chilling cold inside. that stuff is great.

58mark

iTrader: (3)

just got the car back from the shop.... I'm VERY impressed with freeze12. I'm not dreading the 100 degrees days that are around the corner

rdsxfn524

travis401

iTrader: (1)

actually thats not true. its only illegal if you dont have a proper license for it. you can still buy it and use it, if you have the license. however, they no longer issue new licenses for r-12, but the old ones are still valid.

Reid Fleming

iTrader: (2)

When did this happen? As far as I know, the EPA 609 will still allow you to buy R-12. Of course it's been awhile since I looked that up.

travis401

iTrader: (1)

Current laws issue huge fines to anyone possessing, buying, or selling R-12 without the license. But those few who are lucky to have one, or know someone who does, or know of an auto shop with one, have nothing to worry about. The only thing about R-12 that is totally banned in the US (and many other "developed" countries) is manufacture.

Interesting side-note though.....
R-12 was banned in 1994 because it was discovered to deplete the ozone.
R-134a is a greenhouse gas and is contributing to global warming.....

Reid Fleming

iTrader: (2)

HC blends are legal to convert from R-134a (since there are no SNAP rules to follow with R-134a based vehicles). But it's illegal to convert from an R-12 car to a HC. You can convert an R-12 car to R-134a and then convert to HC though.

It's all about money.

Reid Fleming

iTrader: (2)

I want to see some duct temps from Freeze12. I'd be surprised to see anything less than 50°.

58mark

iTrader: (3)

at what outside temp? It was 80 degrees here yesterday and I had to turn the AC down on the way home because it was too dang cold. If it was 100 degrees outside it's going to make a difference

Rayzor32

iTrader: (1)

You can buy R12, you have to have the license. You have to read this booklet and take a test and send them 25 dollars.

sonjaab

In most states and the US in general you cannot BUY r-12 unless you have
a license. R-12 is still for sale but NOT mfrd. in the US. IF anyone still has
any its gonna be real $pendy !!!!!!!!!!!
A place near me has a couple of 30 lb. tanks for $600 each!

Luckily a few years back I bought 6 30 lb. tanks for $99 bucks each because I
own a couple bar/rest. operations with many r-12 units. Never know when one
is gonna need service..............................

Reid Fleming

iTrader: (2)

Both outside temps would make good demonstrations.

58mark

iTrader: (3)

k, I'll pick up a thermometer and do some tests

Fast355

iTrader: (2)

In 100*F weather I promise its going to be 50*+ (probably closer to 60*F at idle) with Freeze 12. Straight R134a is colder and R12 is colder than that. I like my refrigerant colder than that. At IDLE in 100*F weather both my van and truck blow air under 40*F on high fan speed.

At 40 psi of low side pressure that both of my systems run around, the evaporator is around 20*F!!! At the stock 25 psi cut-out the evaporator sits around 0*F. The air at the vents will drop into the low 30s running around on the highway. The Dodge Ram has a temperature probe in the evaporator and I added one for a late 90s Cadillac to the Van.

KITT1983

iTrader: (3)

anything new?

mikeirocz1

iTrader: (1)

I live in South Houston and I converted to 134-A. Over the weekend while sitting in the parking lot at idle it was blowing 60. That was it the middle of the day at 92-94 degrees with heat index of around 100-102 degrees. While cruising the same time of day it will blow aroung 50 degrees. But at night time or early in the morning it blows around 40 degrees driving and 45 driving sitting still. I put dual 12" puller fans on the radiator. Does anyone know if I could put a pusher fan on the condensor or will it counteract with the puller's?

SolarGoldRaptor

So what did you do to convert to 134a, did you just flush the R-12 and replaced it with R-134a, or was there a bit more involved ?

mikeirocz1

iTrader: (1)

I replaced the entire a/c system. Compressor, condensor, lines, evaporator, blower motor, drier.

FSTFBDY

iTrader: (33)

Ive got retro fit kits down in the low 30's out the center vents.

As for whats involved. I have a R12 / R134 machine. So I recycle all the R12
put on Vacuum for awhile to get all the oils out.

put the 134a conversion fitting on. fill with oil/dye and r134a.
Check pressures and temps ad send em on their way.
(have em come back in 1week for a re-test) Most that come in for non-cold AC have a problem somewhere. So I add the dye to check for leaks on the re-test.

Fast355

iTrader: (2)

I was sitting in my truck at lunch this afternoon....In 100ish heat index, in a BLACK 4 door truck....With 38* air blowing in my face..... Sorry R134a will NEVER work for me....I have a HORRIBLE condensor as well.

FSTFBDY

iTrader: (33)

Is that a Dodge Ram 1500? Good thing is atleast the Cond. is off to the side with its own fan.
I just recharged one of them. Black/black leather 4 door. and was blowin in centers @ 42's sitting in our shop @ idle on the machine.

igotta355z28

iTrader: (1)

I dont know where you are getting all your information I just took that stupid lil MACS test and got a license to buy R12.......


I agree with Rayzor he speaks the complete truth on this subject.....I hate AC work cause too many people have dumb biased opinions and since u can buy cans of r-134a everyone and their mama thinks they can service a/c systems. I personally think you should have a license to buy ANY refigerant and the damn licensing process should be a little harder....

Fast355

iTrader: (2)

It is a Dodge Ram 1500, although I would much prefer the condensor/radiator setup used in a Diesel Ram......The little side condensor SUCKS.

mikeirocz1

iTrader: (1)

Does anyone know if you can put a pusher fan on the condensor if running puller fan's on the radiator?

DANNY25SS

I was wondering the same. Just completed the retrofit. If I set at a light it will climb up to about 55* but once I get goin or on freeway it will set at a nice 40* or less at the middle vent. Mind you it was 111* here in vegas today... this morning at 7:30 am it was around 90* and it was under 30* at the vent and I was in traffic...

Rayzor32

iTrader: (1)

yes you can and it helps a lot, I did this to my '89 RS I wired it so it would go on when you turned the a/c on.