WOW!! Talk about easy! Its only $15.00 and it takes about 20 mins. Thanks for the tip!!!

 

I seem to post this every June...
The gas to use in place of R-12 is R-414b, its a drop in replacement for r-12, it requires no oil changes and has the same pressure as r-12, you also gain 8-10% capacity with it..
R-134a poses a couple of problems, first off the 2nd gen original hoses are not lined for r-134a which means the hoses will seep refrigerant, second adding POE oil with the r-134a, basically overfills the system with oil, since the kits give you no means of removing the mineral, most of the mineral builds up in the evaporator which reduces the capacity, then one day you get this big slug of oil that comes back and wipes our the valves in the compressor, if the added heat of compression of the r-134a hasn't already overheated the discharge valves.. Systems made for r-134a specifically always have larger condensers than r-12 system and the condensors are circuited slightly differently with more passes for de-superheating than r-12 condensors..
To the guy who popped the line, you overcharged your system, low suction pressure is a result of a plugged drier, bad txv, or insufficent airflow when the system is full of gas, check for a dirty evap or heater core.
And yes I am a refrigeration mechanic by trade...Max

 

I was the guy that popped the line.

When I asked the other person if he was an AC tech, I wasnt being sarcastic, I was really interested... Just so you know...

so, my question would be, where do you get r414b? Its not offered at the auto parts store I work at.....

Rat

 

Oh, and another question...Since I can legally aquire r12 now, what kind of setup do you need to charge a system? I notice the cans come without any fittings..

Rat

 

i lowuld also like toknow where i can get that r414b at. and the fittings or whatever hardware is required to make it fit on lmy car
thanx

 

Does anyone know where to aquire r414b?

 

Hot shot 414b: This site has a statebystate search engine. Seems that most HVAC suppliers might carry it.
http://www.icorinternational.com/

I have two cars with dead r12 a/c systems. I now have an excuse to buy either the 414b or freeze12 and see how they work.

http://www.dockwalk.com/issues/2000/...hillout1.shtml
http://www.imaca.org/toc.htm

 

Try FREEZE 12, its a lot better...!

 

thanx guys.. i'll prolly end up getting freeze 12 when i can afford it..

 

Here is a supplier:
http://autorefrigerants.com/co00030.htm

 

I can get it for $5 a can....

 

Wow, I started this thread about a month ago. This certainly is a strange day for it to come back up to the top. Today I took my car in to have the AC checked out. First off, the guy tried to get me to convert to R-134b, but I told him I had heard bad things about converting on the internet. While he's trying to tell me how expensive it will be to keep R-12 in there, the owner walks up and says that he has plenty of R-12 that he's trying to get rid of and my car shouldn't take more than 2 pounds.

So they look at the system and tell me that the freon is contaminated. They tell me it is 90.1% R-134a and 9.9% R-12, and they will have to recover the contaminated freon and fill the entire system up with R-12 to check for leaks. My car does not have the R-134a fittings on it. He also says they saw oil around my AC compressor. So they fill the entire system up with R-12 and check for leaks. They don't find any leaks, but the AC is only cooling to 70 degrees. Then he said there was some air in the system that they purged, and added more R-12. Still they couldn't find any leaks. Then he said my expansion valve is sticking, and he doesn't recommend that I run the AC until the expansion valve and drier are replaced. At this point my bill is already over $300 and they want another $341 to do the expansion valve and drier. I told them not to do it, and I would just pay for what was already done.

I don't know very much about AC systems, so here are my questions.

1. Did I get screwed?
2. Why is there R-134a and R-12 in the system?
3. Don't they use different fittings so you can't charge an R-12 system with R-134a?
4. I know the previous owner did not do it, because I know him personally so the freons would have been mixed in the system for atleast a year. If what the shop says is true, wouldn't the system have many leaks in it?
5. Price paid for 2.2 pounds of R-12: $172.19. Again, did I get screwed?
6. What will happen if the expansion valve is sticking?
7. Does this shop sound legit?

Sorry for all the questions, but like I said, I know almost nothing about AC systems. I haven't let any shop work on any of my cars in several years, and I guess I'm just paranoid that I'm getting screwed because it's something I don't know much about.

Anyway, thanks for all your help guys.

 

1) Probably. I say this becuse it sounds like they are parts replacers, at random, until they get it fixed.
TRIAL AND EROR at your expense.
2) IF YOU DO HAVE MIXED GAS
it is because someone added R134 because that is what they could get without a license.
3) A home mechanic may not have left the R134 fitting adapters in place, so you wouldn't know they did it.
4) It would have problems from the mix. Is the compressor noisy? Were the pressure readings normal?
5) That is the highest price I have seen.
6) It wouldn't cool. That could be from the mixed gas causing contamination in youir system.
7) No.

 

vert in vegas and maxthe7man have the right ideas. if there is R12 available it will be easier and cheeper to keep it R12. If the system is open for any length of time problems are bound to come up. TXV's and driers are likely to be bad and if open for an extended period nothing short of replacing the entire system will work. the R414b and other drop in replacements are available but not from auto supply houses, HVAC supply houses have it. the automotive service industry has recommended R134a conversions instead of drop in replacement gases, I don't know why. You will find alot of "parts changers" doing A/C work at repair shops. I had a Volvo dealer tell my mom that the compressor was dead on her 240DL a couple years ago. after I checked it out I found the TXV bulb was broken off and the expansion valve was not working. she would have replaced the compressor and it still would not have worked then they would have kept going until they found the part that was bad. use a shop that specialises in A/C repairs and let them do the work it will save you in the long run. a clean system with no leaks should work for many years trouble free. I am also a 10year commercial A/C tech.

 

To my knowledge no previous A/C work has been done.
I'm in Canada so I'm not sure about the 134/R12 issues and 're-charging' the system.

The A/C will not turn on, and the light on the logicon does not light either so...

Please list the things that I should check BEFORE I take it to an A/C shop so I know what to ask about and make sure they are going to do to 'fix' the system.

Thanks

 

just for the record, my family has had pretty good luck with MIDAS... any horror stories from them anyone?

 

Thanks for all the info guys, you pretty much confirmed my suspisions. This is exactly why I always do all the work on my cars. I guess I should just learn more about AC systems before getting working on or getting one worked on again. Thanks for the info Vert in Vegas and Tims. Oh yeah, to answer your question, no the compressor isn't noisy, and the guys didn't say anything about the pressure in the system, they just said that it wasn't leaking anywhere. Also, they told me if I run the AC while the expansion valve is sticking it could build up too much pressure and blow a hose or something. Could this happen?

 

if the expansion valve is stuck closed the compressor will pump the evaporator into a vacuum and force the refrigerant into the condenser. this should not cause the hose to blow but it could damage the compressor if run for extended periods. it will give you no cooling effect so there is no need to ruin the otherwise good compressor. that is why the guys were asking about the pressures. if the low side gauge is reading in a vacuum then this tells you you have an obstruction. either the filter/drier is plugged or the expansion valve(could be pinched line or oil logged evap or condenser also). a competent A/C mechanic should be able to diagnose this problem in a couple of minutes. high discharge pressures could mean over charge or blocked condenser coil this could blow the hoses.

 

This place I went to today wants $290 to vacuum the system out of the R12, check for leaks, and refill it with R12. Am I gettin screwed?

 

Without benifit of lube...Trust me.

 

You know of any good shops down there in Tucson J-Rat??

 

Yeah, me! Seriously...I do all my work myself. I have been educating myself and asking alot of questions. The system in my 7 now is one I assembled and charged myself. No, I didnt put a vacuum on it, so it may have some non-compressable gas in the system, but who cares? IT blows cold.... I run regular static pressure checks on it to see if its leaking, and it isnt. Whats wrong with your system? If its just in need of a minor charge, I would seriously consider NOT taking it to an A/C specialist. I am not trying to condemn all the A/C people in the world, in fact I believe VertnVegas here is one, and he has some good answers. Its just that being an AC specialist in Tucson (or Pheonix for that matter) makes you an incredibly popular guy. Kinda like being the only guy at a party with beer. So they command quite a premium. I am still amazed that someone from the cooler climes (i.e. the rest of the USA) hasnt chimed in with the "take it all out, it saves weight" B.S. They obviously have never lived here... Anyways, if you tell me whats wrong, and you dont mind a commute to Tucson (since it would take some pretty good convincing to get me to Pheonix), I will be more then happy to look at your system and fix it free of charge. All you pay is parts and gas. Oh, and a six-pack or two.

Rat

 

Well, my A/C doesnt blow cold anymore. So, obviously its in need of a charge. And I have no idea if it is leaking at all. Problem is, I cant get ahold of any R12 coolant for you to use. PM me and we can work out details or somethin. Thanks for responding.

 

I appreciate this discussion. I've had the A/C charged in my '91 only a couple of times since I've owned it. I had it charged again last month and now it's not blowing cold anymore. I guess it's safe to assume there's a leak, but is there a way to test for leaks that gives immediate results or is the dye (where you have to bring it back in a week) the best method? The Firestone near me seems to do a good job...I'm just hesitant to trust any shop with anything more that an oil change. I'll let them treat this problem, but I want to be educated about it all before I do. Any suggestions about what I should ask for and what I should know?

 

I tried to fill my system after converting to r134 by an A/C shop. Does anyone know how the system takes the r134? I put it in the low side it it seems like it takes forever for the first can. The system did not get cold. How long should it take and am I doing something wrong with how I'm trying to fill?