R-12 to R-134 - LotusTalk - The Lotus Cars Community
 2Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 28 (permalink) Old 12-05-2011, 10:03 PM Thread Starter
Registered User
 
karmavore's Avatar
 
Join Date: Aug 2010
Location: Maryland
Posts: 204
R-12 to R-134

Has anyone done a proper A/C refrigerant conversion? If so, did you use OEM parts? How'd the job go? Does it cool correctly?

Id like to upgrade my radiators but the prospect of converting to R-134 is a bit daunting.

Thanks fellas

Luke Colorado, Super Spy. - Lotus Owner No Longer

1987 Zender Widebody 560SEC | 2013 Honda Fit EV (#269)
karmavore is offline  
Sponsored Links
Advertisement
 
post #2 of 28 (permalink) Old 12-06-2011, 03:01 AM
anglophile in exile
 
Aedo's Avatar
 
Join Date: Jan 2006
Location: Oz
Posts: 5,453
Haven't done it on a Lotus but have done it on a Suzuki - all I did was change the oil and the receiver/dryer then charged with R134. All worked with no problems
Aedo is offline  
post #3 of 28 (permalink) Old 12-06-2011, 04:52 AM
Registered User
 
Join Date: May 2008
Location: Florida
Posts: 1,292
Lucas,

Avoid converting to R-134a if at all possible. It will never cool as well.

If you have to change, in order to do it properly, at minimum you need to flush all the lines and evaporator well and replace the compressor, expansion valve and receiver/drier. You will be replacing the condenser anyway and you'll want as big a unit as you can fit. I used a 27" x 10" unit in mine.

Ideally you'd want to replace the hoses as well with a barrier type as the existing ones can be prone to leakage with 134. That makes the overall job more complicated and costly.

You could keep the compressor but it needs to be removed and all the old oil flushed out. The reason I said to replace is I can point you to a source to buy a new one for $120
so you might as well put a new one in while you're there.

If you're going to do it yourself, email me and I'll send you some info and links to help you get the job done right and as cost effective as possible.

Cheers,
Jim

Jim
1995 S4s
lotus4s is offline  
 
post #4 of 28 (permalink) Old 12-06-2011, 04:55 AM
Registered User
 
Join Date: Apr 2010
Posts: 159
I had the experience with 2 lotus esprits --my 87 hci, then my 94 s4.

My advice, do NOT do it. If your car's a.c. is designed for R12, everything from hoses to a thorough flushing of the compressor, oil, must be done. It takes a bigger conversion than just switching the oil and refrigerant.

In both my cars, the R134 did NOT cool nearly as well. I'm in Louisiana, and the summers are very, very hot. With R12, no problem.
judgea is offline  
post #5 of 28 (permalink) Old 12-06-2011, 06:11 AM Thread Starter
Registered User
 
karmavore's Avatar
 
Join Date: Aug 2010
Location: Maryland
Posts: 204
How much longer is R-12 going to be around? I imagine you did it for a reason not for fun, right Jim?

Luke Colorado, Super Spy. - Lotus Owner No Longer

1987 Zender Widebody 560SEC | 2013 Honda Fit EV (#269)
karmavore is offline  
post #6 of 28 (permalink) Old 12-06-2011, 06:51 AM
Registered User
 
azac's Avatar
 
Join Date: Sep 2006
Location: Tucson, Arizona
Posts: 433
Quote:
Originally Posted by karmavore View Post
How much longer is R-12 going to be around? I imagine you did it for a reason not for fun, right Jim?
Since 1994 the same question has been asked. The correct answer is R12 will be available in the foreseeable future. In different parts of the U.S. markets are different and prices vary widely within those markets. You are only 2500 miles away, so come on down as we charge only $39/lb. .
Seriously, keep it as designed, check the system for leaks and check around for a/c specialists for pricing.

196? Seven - long gone
2005 Storm Titanium Elise - sold
2008 blue 2-Eleven - track toy
2011 Carbon Grey Evora S
1959 Ford Anglia project
2008 white 2-Eleven - track toy too/two
azac is offline  
post #7 of 28 (permalink) Old 12-06-2011, 09:06 AM
Registered User
 
Join Date: May 2008
Location: Florida
Posts: 1,292
I agree, doesn't seem to be a supply problem anytime soon.

Actually I never converted. Both of my S4s's had R134a and the S4 I had came with R-12. The R12 was so much better in the S4 that I was going to convert the 134 in my current S4s to R12 which was the reason I did the whole radiator and ac system modification that I posted about in your rad thread.

I ended up sticking with the R134a in my new system as it now cools much better than the OEM one that was in it. Still not quite as good as the S4 with R12 was but acceptable.


azac, are you with Arizona Mobile Air?

They are one of the sources I used in my project and have a great auto a/c forum.

Jim

Jim
1995 S4s
lotus4s is offline  
post #8 of 28 (permalink) Old 12-06-2011, 09:35 AM Thread Starter
Registered User
 
karmavore's Avatar
 
Join Date: Aug 2010
Location: Maryland
Posts: 204
Ahhh... got it. Thanks boss.

Luke Colorado, Super Spy. - Lotus Owner No Longer

1987 Zender Widebody 560SEC | 2013 Honda Fit EV (#269)
karmavore is offline  
post #9 of 28 (permalink) Old 12-06-2011, 02:35 PM
Registered User
 
TechTac's Avatar
 
Join Date: Jun 2011
Location: Colorado
Posts: 96
Garage
Mine came converted, and even after a recharge, it doesn't work well at all. Car will start to overheat in traffic with it on, and it never gets reasonably cool if it's much over 80 degs outside...

______________________________
1993.5 Esprit SE
1986 TVR
TechTac is offline  
post #10 of 28 (permalink) Old 12-06-2011, 05:59 PM
Registered User
 
Join Date: May 2008
Location: Florida
Posts: 1,292
Tech,

Assuming your fans and water pump are working properly, your radiator cooling fins are probably clogged with debris. Only fix is to drop the radiator assembly, remove the radiator and physically clean it. See the pic that Travis posted in the radiator thread.

I assume that's why you were asking about it in your thread.

This is a maintenance item that needs to be done every few years but most people never do because it's such a PITA job...

Jim
1995 S4s
lotus4s is offline  
post #11 of 28 (permalink) Old 12-06-2011, 06:05 PM
Registered User
 
Join Date: Apr 2010
Posts: 159
Techtac, you need to convert back to R12 with a proper flushing of the system, new dryer, etc. I am in the hottest climate and my car runs cool with a.c. on and no matter what, so you do need to check your cooling system.
judgea is offline  
post #12 of 28 (permalink) Old 12-06-2011, 06:15 PM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,091
Even if you do everything "by the book" and convert an R-12 system to -134 you will lose about 10% of the cooling capacity. The components were not designed to use -134 and are not sized accordingly to use it. R-12 is and will be available for the foreseeable future and if you can't get it there are drop-in replacements available, R-414b as an example which will give you the same cooling capacity as R-12. Of course this all assumes the A/C system and the engine cooling system is well maintained and operating properly. In the Lotus it is very common for the radiator and the condenser coil to get plugged up with debris. They must be removed to be properly cleaned to maintain full airflow.
David Teitelbaum
jtrealty is offline  
post #13 of 28 (permalink) Old 12-06-2011, 09:15 PM
Registered User
 
azac's Avatar
 
Join Date: Sep 2006
Location: Tucson, Arizona
Posts: 433
Quote:
Originally Posted by lotus4s View Post
azac, are you with Arizona Mobile Air?

They are one of the sources I used in my project and have a great auto a/c forum.

Jim
No, Tim Bohringer (AMA) is in Phoenix and my shops (Arizona Auto Refrigeration) are in Tucson.

Bob

196? Seven - long gone
2005 Storm Titanium Elise - sold
2008 blue 2-Eleven - track toy
2011 Carbon Grey Evora S
1959 Ford Anglia project
2008 white 2-Eleven - track toy too/two

Last edited by azac; 12-07-2011 at 08:05 AM. Reason: mispelled Tim's name
azac is offline  
post #14 of 28 (permalink) Old 12-06-2011, 10:50 PM
Moderator
 
sleekgt's Avatar
 
Join Date: Aug 2011
Location: San Jose, California
Posts: 3,702
Garage
Quote:
Originally Posted by karmavore View Post
Has anyone done a proper A/C refrigerant conversion? If so, did you use OEM parts? How'd the job go? Does it cool correctly?

Id like to upgrade my radiators but the prospect of converting to R-134 is a bit daunting.

Thanks fellas
My 88 Esprit previous owner converted it to R134. It's not working quite yet, but will have R134 topped off next week -we'll see how it goes. FYI I may need this AC as I'm driving to Los Angeles around Dec 23 - in previous years, it can be high 70s in downtown LA that time. I kid you not.
---------------------------------------------------------------------

You're in MD, so maybe my situation doesn't apply.

I did a low buck conversion on my wife's 91 Mustang - had a shop evacuate the R12. Then I got the R134 kit, followed instructions, and it works fine (since 2005). No additional flushing, no replacement of ANY hardware. It runs nearly as cold as before - car has black interior too.

I'd swag it as 85-90% coldness of R12 - good enough for us.

Now, San Jose, CA can get hot, but it doesn't get as humid as MD. As others said, to get the proper efficiency, etc., it's gonna take serious $$ and an Esprit ain't the lowest cost car to do this.

Disclaimer: yes - I know that the seals may wear out faster, etc. but we're talking about a 20 year old car already - not much to lose at this point.

My advice: first try repairing leaks and get more R12. But be forewarned - if the leaks aren't addressed, you're leaking at $39/lbs. Once you load R134, you can't go back easily to R12.
sleekgt is offline  
post #15 of 28 (permalink) Old 12-06-2011, 11:00 PM
Terry
 
t955152's Avatar
 
Join Date: Oct 2010
Location: Bay Area
Posts: 2,188
sleekgt! i saw your car today on Zanker!
t955152 is offline  
post #16 of 28 (permalink) Old 12-07-2011, 11:58 AM
Moderator
 
sleekgt's Avatar
 
Join Date: Aug 2011
Location: San Jose, California
Posts: 3,702
Garage
Quote:
Originally Posted by t955152 View Post
sleekgt! i saw your car today on Zanker!
Yep - I try to takes spin at lunch whenever possible. Extended reliability testing for drive to San Diego on Dec 24. No lunchtime spin today as I'm at work trying to put out some lunchtime fires:-(. Maybe another run tomorrow.

2100 miles in 9 weeks - fun stuff!
sleekgt is offline  
post #17 of 28 (permalink) Old 12-07-2011, 06:39 PM
Registered User
 
amanda11270's Avatar
 
Join Date: Jun 2011
Location: Northeast US
Posts: 909
I have posted on this forum previously in regard to recharging AC systems, if you would like to do a very simple conversion and know someone that can purchase you refrigerant, there is a product called HOTSHOT, that is a blend of refrigerants to mimic R-12 perfectly. Its not a snake oil like those auto parts store crazy name refrigerants that are just R-134 in another can or anything consumer grade, its a professionally sold drop in R-12 replacement I work as a refrigeration technician and have used this R many times in the past. It only comes in a 30LB cylinder though and its around $250-$290, but if you know a technician he can probably charge it for you and then you would only buy the refrigerant you need from him. I would still recommend doing the filter dryer just for good measure, or not really, like I said, HOTSHOT is a drop in replacement. I used this product in my 73 Mustang, and 78 Trans Am, which were both of course R-12 systems with great results. 134A isnt going to do the trick in a 12 system in a dry-heat climate if you like the AC really bitter cold. If you live in a humid climate you may not even notice the difference between 134A and R12 or even HOTSHOT. The humidity in the air is always a big factor in air conditioning. Anytime you add R-134A to a R-12 system its alot of guess work because it originally wasnt made for R-134A. And the ambient temperature the system was charged at isnt the temperature the system is constantly going to be working at, so its never going to be the same as R-12. And unless you are going to physically remove the compressor and dump the oil out of it, then disassemble it and clean it with parts cleaner, its always going to be contaminated with an oil thats not compatible with R-134A, its just a matter of how much contamination. So unless you are going to go that far you really are not doing a full correct textbook R134A conversion. The only factor in how long the system will last after a 134A conversion I feel is the resistance of the seals, orings, hoses to the corrosion situation that is caused by the mixing of the R-12 mineral oil with the 134A refrigerant (134A uses PAG oils), and who knows how long thats gonna be. Really this whole write up isnt that big of a deal, I have put 134A in without changing any system components too myself in R-12 systems in the past, I guess I just felt like typing tonight LOL. But if you really want to be correct about it!

Last edited by amanda11270; 12-07-2011 at 07:21 PM.
amanda11270 is offline  
post #18 of 28 (permalink) Old 12-07-2011, 07:53 PM
Registered User
 
azac's Avatar
 
Join Date: Sep 2006
Location: Tucson, Arizona
Posts: 433
Not to be a wet rag, but the use of Hot Shot in car a/c brings with it EPA requirements (conditions of use) that include unique service fittings specific to that refrigerant, labeling, conversion of hoses to barrier type if they are not already, use of dedicated service and recovery equipment for that refrigerant. Practical considerations include finding someone to service it later, as virtually no automotive shops deal with it and the fact that Hot Shot contains 50% R22, which degrades some materials used in sealing components (compressors)as well as the old style rubber hoses.

196? Seven - long gone
2005 Storm Titanium Elise - sold
2008 blue 2-Eleven - track toy
2011 Carbon Grey Evora S
1959 Ford Anglia project
2008 white 2-Eleven - track toy too/two
azac is offline  
post #19 of 28 (permalink) Old 12-07-2011, 08:23 PM
Registered User
 
91MR2's Avatar
 
Join Date: Jan 2008
Location: Pillaging, just for fun...
Posts: 1,328
I will be referencing this thread soon, I need a re-charge...

2012 Lotus Evora S GP Edition #14/14
1995 Lotus Esprit S4
1991 Toyota MR2
1987 Renault GTA

www.91MR2.multiply.com
91MR2 is offline  
post #20 of 28 (permalink) Old 12-08-2011, 05:37 AM
Registered User
 
Join Date: Nov 2009
Location: New Jersey
Posts: 3,091
Using any "drop-in" replacement for -12 will entail certain restrictions. You have to label the system, sometimes change service fittings and other parts, and you are limited to the # of times you can "top off" because most of them are *blended* refrigerants. When they leak you lose different portions at different rates so after several cycles you no longer have the correct amounts of the various types of refrigerant and now must remove it all and start all over with fresh. This means you should have a very leak-tight system so you don;t need to top off )or at least not often). The good news is drop-in replacements are not very expensive compared to -12. For my money you are best served by making the system as leak-proof as you can and stay with -12. It is about $30 a LB and you need less than 2 1/2 lbs so we are not talking about something which will break the bank here. If you have a real leaker (which according to the EPA you have to fix anyway) drop-in replacements are the cheaper way to go. You do have to find a shop that can service you the way you want though. In an area that is hot (the south for instance) there are a lot of shops to pick from and you should be able to find one that can help you out.
David Teitelbaum
jtrealty is offline  
Sponsored Links
Advertisement
 
Reply

  LotusTalk - The Lotus Cars Community > Lotus Discussions > Lotus Esprit

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the LotusTalk - The Lotus Cars Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome