| Author |
Message |
Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1537
Registered: 4-2002
| | Posted on Thursday, June 26, 2003 - 5:52 pm: | |
I guess I'd better leave my old leak detector on the shelf.
In the olden days of yore, it was common to use a gas flame gizmo with a tube attached to detect leaks. You put the tube close to suspect areas, the surrounding gasses (hopefully just air) get sucked up thru the tube and exposed to the flame. If the flame turned color, R12 was present. If the car blows up, Duracool is present. <g> |
DGS (Dgs)
Junior Member
Username: Dgs
Post Number: 106
Registered: 5-2003
| | Posted on Thursday, June 26, 2003 - 5:34 pm: | |
Most of the sites selling hydrocarbon refrigerants say so, but to be sure, I checked the dupont site.
To summarize from Dupont ART-27 (h45948-2.pdf), "Suva 134a (HFC-134a) for Mobile Air Conditioning": Not at ambient temperature and atmospheric pressure.
So as long as you don't heat it or apply a compressor ... or as long as there isn't any air in the system.
But the same caveats apply to hydrocarbon gasses. If there's no oxygen, they don't burn.
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Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1536
Registered: 4-2002
| | Posted on Thursday, June 26, 2003 - 5:06 pm: | |
DGS: I'm only famaliar with R12. Is R134a flammable? |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 767
Registered: 3-2001
| | Posted on Thursday, June 26, 2003 - 4:44 pm: | |
I have used Freeze 12 (in another car) and it works well. I prefer R12 but it is getting up there in price. Last year I could still buy it for $25 per lb. and I was ok with that but it is higher that what I would like to buy now. |
DGS (Dgs)
Junior Member
Username: Dgs
Post Number: 104
Registered: 5-2003
| | Posted on Thursday, June 26, 2003 - 4:43 pm: | |
Er, Hans. Check the properties of R-134a. |
Walt Pfirman (Waltp)
Junior Member
Username: Waltp
Post Number: 52
Registered: 7-2002
| | Posted on Thursday, June 26, 2003 - 4:41 pm: | |
I've had good results in the past with RB-276. It's a drop in replacement for R-12. Nothing to change, just vacuum and charge |
Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1535
Registered: 4-2002
| | Posted on Thursday, June 26, 2003 - 3:51 pm: | |
Boy, I'd never use a propane/butane refridgerant. Ever hear of FLAMMABILITY? 308 hoses have been known to wear thru in places, etc. Do you really want this stuff escaping in large quantities into either your engine compartment or your passenger compartment?
I'd reserve this stuff for the Mafia. They can put it in cars of those who received the cut off horses head the night before. |
Lawrence Coppari (Lawrence)
Member
Username: Lawrence
Post Number: 683
Registered: 4-2002
| | Posted on Thursday, June 26, 2003 - 10:35 am: | |
I've used Duracool in my old MB for 7 years. It is a mix of propane and butane. No problem with it. Also use it in my Porsche. The website for Duracool is www.duracool.com if anyone is interested.
Thanks for all the advice on charging. I'll evacuate it this weekend and charge. |
Peter Delaney (Delaney)
New member
Username: Delaney
Post Number: 16
Registered: 2-2002
| | Posted on Wednesday, June 25, 2003 - 9:45 pm: | |
Just did a search on the aircondition.com board for ES12A. Seems like quite a few people use it for cars ... they also add propane to spike it! |
Peter Delaney (Delaney)
New member
Username: Delaney
Post Number: 15
Registered: 2-2002
| | Posted on Wednesday, June 25, 2003 - 9:36 pm: | |
I made a mistake ... it's ES12A .. not EV12A.
Pretty tempting when you have to do nothing to the system for the conversion. But I understand your comment on caution.
Thanks for the feedback. |
Verell Boaen (Verell)
Member
Username: Verell
Post Number: 867
Registered: 5-2001
| | Posted on Wednesday, June 25, 2003 - 9:21 pm: | |
Peter,
I just searched the aircondition.com BBS & their archives:
http://www.aircondition.com/wwwboard/
It's the A/C equivelant to the FerrariChat. There's no mention of EV12A!! That's surprising because some of the members are pretty deep into alternative refrigerants. I'd be leery.
You could try asking about it there. Maybe it's better known under some other name.
AHAH, you miss-typed the name, it's ES12A. There are quite a few EnviroSafe posts & 3 ES12A posts on the AirCondition BBS. Just plug ES12A into their search engine. Sounds like ES12A is a blend of propane & something else. It is also sold under the name "Enviro-Safe".
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Peter Delaney (Delaney)
New member
Username: Delaney
Post Number: 14
Registered: 2-2002
| | Posted on Wednesday, June 25, 2003 - 4:30 pm: | |
Has anyone heard of EV12A as a replacement for R12 or R134A. It's meant to be compatible with ALL hoses, seals, oils etc ... i.e. NOTHING needs to be changed out. Sounds too good.
The web site for info is:
http://www.autocool-refrigerants.com/product.htm#tech%20page
Comments please.
Pete
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Verell Boaen (Verell)
Member
Username: Verell
Post Number: 860
Registered: 5-2001
| | Posted on Wednesday, June 25, 2003 - 3:16 pm: | |
Larry,
Oxygen isn't the only source of A/C corrosion.
Under the right conditions, the freon will break down & combine with residual moisture to release free flourine & also form hydroflouric acid. Talk about corrosive... Got this from some A/C training material years ago. Can't remember the specifics, but am pretty sure this is the major cause of A/C internal corrosion.
R134a CHARGEING/TOPPING OFF THREAD
---------------------------------
You may find this long thread useful. We ended up coming up with a lot of detail/tips/web sites on this topic:
http://www.ferrarichat.com/discus/messages/256120/105688.html
I certainly learned a heck of a lot about A/C I never new in the process. |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 34
Registered: 5-2003
| | Posted on Wednesday, June 25, 2003 - 1:51 pm: | |
The most important thing is to run for at least 20 min after a full vaccum is obtained. Then fill with the recommended weight of R12 or whatever it calls for.
There are different jet sizes inside so the appropriate refrigerant must be used.
aehaas |
Lawrence Coppari (Lawrence)
Member
Username: Lawrence
Post Number: 681
Registered: 4-2002
| | Posted on Wednesday, June 25, 2003 - 1:07 pm: | |
I know I have to remove the moisture. The humidity here is very low about 15% so I do not have much moisture to remove. If I lived on the coast, the problem would be more severe.
Aside from freezing up, the systems tend to get eaten from the inside out due to corrosion. Most varieties of CORROSION NEED OXYGEN to progress. That is why I want the oxygen out. That along with our very low humidity is why I was thinking about simply purging it. The moisture in the system will evaporate into the gas stream as it would if I applied a vacuum. Probably not as fast though.
I have a small vacuum pump so I'll proceed with the pump. |
Steve (Steve)
Member
Username: Steve
Post Number: 428
Registered: 2-2001
| | Posted on Wednesday, June 25, 2003 - 11:54 am: | |
JRV right again. The vacuum boils off any of the moister. I just did mine again . I hook up a vacuum (compressor) and pump it down to 28"-30" and let it run for 1 hour. Turn off the pump and let it set for a few hours and if no leak just attach the 134a and open the valve filling to a low pressure reading of 25-40 psi which is about 80% full in a R12 system. Now blows 40 degree air out of the front ducts under the radio. Cool |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1809
Registered: 11-2002
| | Posted on Wednesday, June 25, 2003 - 9:14 am: | |
>>The reason to pull a vacuum is to be sure there is no moisture in the system which may then freeze in the expansion tube and clog the lines. The vacuum also aids in the initial charge by actually pulling the charge into the lines without having to start the engine and run the compressor<<
The above is correct.
Additionaly a vacum of at least 28inHG must be maintained for a minimum of 30 minutes (@ 28inHG water boils in 15 min.) to Boil and the Evacuate "the moisture". |
Steve Magnusson (91tr)
Intermediate Member
Username: 91tr
Post Number: 1914
Registered: 1-2001
| | Posted on Wednesday, June 25, 2003 - 9:13 am: | |
nitrogen not hydrogen (but we knew what you meant) |
Lawrence Coppari (Lawrence)
Member
Username: Lawrence
Post Number: 680
Registered: 4-2002
| | Posted on Wednesday, June 25, 2003 - 9:12 am: | |
I have a MIG welder. It blankets with CO2. So the gas is no problem.
Ive thought about attaching it up to the intake to pull some vacuum. |
Frank Parker (Parkerfe)
Advanced Member
Username: Parkerfe
Post Number: 2577
Registered: 9-2001
| | Posted on Wednesday, June 25, 2003 - 9:11 am: | |
Why would want to remove the oxygen without removing the other gases in air ? The 21% of air that is oxygen will not cause a problem. It is the other 79% portion that poses the moisture problem. |
Steve Magnusson (91tr)
Intermediate Member
Username: 91tr
Post Number: 1913
Registered: 1-2001
| | Posted on Wednesday, June 25, 2003 - 9:04 am: | |
You guys are creating more work/cost/hassle! A second gas to buy, store, and futz with? -- one is quite enough for me thank you...
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Lawrence Coppari (Lawrence)
Member
Username: Lawrence
Post Number: 679
Registered: 4-2002
| | Posted on Wednesday, June 25, 2003 - 8:53 am: | |
When you open the system by removing the compressor, air gets in. FYI, there is oxygen in air. That's how oxygen gets in.
So to get rid of moisture, why not just 'blow dry' with carbondioxide. |
DamonB (Prova7)
Junior Member
Username: Prova7
Post Number: 73
Registered: 7-2002
| | Posted on Wednesday, June 25, 2003 - 8:49 am: | |
The reason to pull a vacuum is to be sure there is no moisture in the system which may then freeze in the expansion tube and clog the lines. The vacuum also aids in the initial charge by actually pulling the charge into the lines without having to start the engine and run the compressor.
Pulling a vac is easy by rigging a fitting to the intake of an air compressor. I even did one by rigging a fitting to the intake manifold and letting the engine itself pull the vac while running! This of course assuming the motor can pull sufficient vacuum. |
Frank Parker (Parkerfe)
Advanced Member
Username: Parkerfe
Post Number: 2574
Registered: 9-2001
| | Posted on Wednesday, June 25, 2003 - 8:45 am: | |
How would "oxygen" get in the system in the first place ? Did you mean air ? FYI, air is mostly nitrogen, not oxygen. |
Lawrence Coppari (Lawrence)
Member
Username: Lawrence
Post Number: 678
Registered: 4-2002
| | Posted on Wednesday, June 25, 2003 - 8:26 am: | |
I am assembling a system with a new Sanden compressor and receiver/dryer. Next step is charging the system. I realize that pulling a vacuum is recommended.
I believe this is necessary so that all the oxygen is removed from the system. Free oxygen permits corrosion to occur so it seems logical to me to get the oxygen out of the system.
But what about purging the system with either nitrogen or carbon dioxide. This would push all the free oxygen out. Many years ago I purged with R12 when it was legal to vent and when it was cheap. It worked just fine. The system on that car still operates.
What do you guys think? |