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Proper R12 to R134a Conversion (Sanden)

Old 07-01-2008, 06:39 PM
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Default R12 to R134a Conversion (Sanden)

Since I scoured h-t for the proper way to do this and came up with nothing (beyond idle speculations) I decided I would post this.

This is straight from Sanden as cited. I have always heard that R134a should be 85% of R12 amount but this says differently.
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Backstory
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General Unorganized Info
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-Obviously you have to start by putting R134a valves and such on your system if it has not been done. These can be purchased at any auto parts store.
- I talked to the tech department at Ready Aire and he said that their rule of thumb is 80% of R12 specification.
- Since the system was completely evacuated and flushed they said to use 7 ounces of PAG-46
- James89DX (who is also delving into the ac world) used 4 ounces of PAG because he only changed his evaporator core and expansion valve, not flushing the system.
- I had my lines rebuilt so they are R134a lines. Because of this I will vacuum my system longer. If you are not having your lines rebuilt and changed then keep within the service manual specs because over vacuuming will remove the mineral oil (what R12 systems are lubricated with) out of the lines, allowing the R134a to escape because the molecules are smaller than R12.
- Change all of the O-Rings to R134a (they are green)
-Do not touch them with your bare hand, use gloves. Coat them very conservatively in dialectic grease.
- Flush with flush made for a/c systems if you are changing the entire system out. If you are just replacing a part, like a used condenser, flush it with denatured alcohol as it will not take out the needed mineral oil that has been absorbed over time.
- You can just switch to using R134a, but be sure to use the proper amount, as too much will blow the system.
- It is a really good idea to upgrade to an aftermarket condenser fan, as the stock is not efficient enough for R134a
- Even when fully converting with hoses and new compressor and o-rings, it is still the same parts, designed originally for R12, so it will not be as efficient. That is why people say R12 is colder than R134a. This is not entirely true, as my mustang was designed for R134a and is icy cold. It is that an R12 system is not efficient for R134a. The condenser and evaporator core are smaller than they should be, the stock honda fan is cruddy etc...
- I heard or read somewhere that the regular bottle of PAG is better to use than the kind you charge into the system like you would freon.
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Steps I took
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-I used and am using the appropriate steps according to Sanden's website, the service and owners manual for my car and the technical support from the manufacturer of the compressor I purchased. I am leaving these details out of my simple steps that I wrote because the sources for them are either suggested or given. So when in my steps I say "remove compressor" or "charge system" it is implied that you do this according to the steps laid out by Sanden/Honda service manual/Manufacture of your parts.
-Some of the things I am not going to go into full detail about because they are common sense or you can see it as you go.
- If there is refrigerant in your system the legal thing to do is have it discharged properly. My system leaked completely out on its own and then the compressor blew up, so unfortunately mine was discharged on its own.
- Although it is kinda common sense and like a puzzle with pieces that fit together a certain way it helps to either take a picture of your engine bay or have another car with an intact system accessible for visual reference when putting it all back together.
- Make sure you do not get any foreign crud in the system.
- If your drier is off for more than a few hours then replace it.
-Really I would just replace it because it is probably old or ruined with moisture anyway. It is a 30 dollar part and if it is moisture logged your system will not be as cold as it should be.
- Absolutely replace your expansion valve. That crap around it is some kind of ac tape that can be had at any ac place (the place that rebuilt my lines gave me a strip for free). The old nasty residue cleaned off with acetone.

1. Take off your dash. Be sure to remember the little ground.
2. Take out the blower motor and evaporator.
2.1. Clean the evaporator off since it is probably caked in crap.
2.2. Replace the expansion valve. There are two types, a spiral looking one and a bulb one, I do not know what has what, so replace with whatever type you have.
2.3. Flush out with whatever type of flush is appropriate for your situation. I used a squeeze bottle and squeezed some into the system then blew it out thoroughly with the air compressor.
3. Remove compressor. When replacing take notice of whether it is packed with oil in it or not, it can go either way.
4. Remove lines.
4.1. Flush all the lines appropriately.
4.2. Have your hoses rebuilt. Mine was $105 for the two that have rubber in the lines. You do not have to do this, but you should if you like to do things the right way.
5. Put it all back together. I did mine from the firewall forward. Make sure you reconnect and have not kinked your drain hose.
5.1. Evenly distribute the appropriate amount of PAG oil throughout your entire system. In the compressor use the suction side. How much and where is up to you.
5.2. Be sure you have reconnected everything and have all the O-rings replaced. Make sure everything is torqued to the appropriate level.
6. I replaced my fans with aftermarket fans. R134a requires a more powerful fan than stock for the best efficiency. It is up to you if you want to do this or not, and how you want to do it. I went ahead and replaced my radiator fan as well since I did not like the look of a crappy stock radiator fan coupled with a slim nice aftermarket one. I used the Hayden brand fans, mainly because they were cheaper and in stock at the parts places. I used a 10 inch pusher for the condenser and a 12 inch puller for the radiator. Bigger than 12 will not fit on the radiator. I think 12 will fit on the condenser however I used a 10 inch. If you decide to put a pusher on the front of the condenser you will have to modify the bumper support accordingly.
7. I charged my system exactly per the procedures in the service manual for my car. In fact, I did everything in accordance to the service manual, unless there was a glitch or something needed to be tweaked because of some nuance in my system. I will not post copyrighted material, but you can get anything off the internet and I know craigslist has tons of service manuals for sale in various cities.
7.1. Place gauges and pump according to the instructions and manuals.
7.2. Start the vacuum. Have the valves closed, start vacuum then open the valves.
7.3. Vacuum for at least 15 minutes. If it is not holding at around 27 in-hg then there is probably a leak in your system. Close valves see that it is holding then open valves and vacuum another 15 minutes. Close valves and replace vacuum with refrigerant can.
7.4. Here is where you actually charge the system. Open the refrigerant can valve and in the center of your gauges let out the air in the can.
7.5. Open the high gauge valve and let in about 10.5 ounces of refrigerant. After charging with 10.5 oz close the high gauge valve. (do not start your engine with the high gauge valve open, do not open the low gauge valve).
7.6. Start the engine with the A/C on cold and high. Run the engine at 1500-2000 rpm and make sure the low pressure drops.
7.7. Open the low gauge valve and charge with the appropriate amount of R134a. Have engine at 2500 RPM. Do not open high gauge valve. When the sight glass has no bubbles it is charged.
7.8. When it is charged close the valves and the valve on the can, disconnect the hose the can is on from the gauges.
7.9. Remove the hoses from your system. The faster the better.
-These steps are how I followed the service manual. I would suggest you source your own copy of your service manual and follow its steps explicitly. I can not guarantee that this is all 100% exact.
-Now you are done.
I have absolutely zero A/C experience or background. I can not diagnose any problem or anomaly, including my own. The service manual has very detailed troubleshooting parts and that is where I would start if you run into any problems or have any problems to start.
- This is only an account of how I did my system. Every step I took and posted were based on me following the service manual. James89DX did the exact same thing (aside from a few different steps based on him using his stock compressor) and his pressure readings were perfect following regular guidelines.
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Works Cited:
Honda Motor Company, LTD.. (1987). Shop Manual Honda Civic Chassis Maintenance and Repair (1st ed.)
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Recommended Procedures for Sanden R-12 Compressors Retrofitted with R134a

The use of R134a in mobile A/C systems designed for R-1 2 refrigerant causes higher discharge pressures (as much as 10-15%) and necessitates changing the compressor lubricant from mineral oil (5GS) to PAG oil (Sanden's SP-10 or SP-20) to ensure compatibility.


These changes result in greater wear to the internal components of the compressor. Therefore, to ensure consistent and expected reliability, Sanden does not recommend using R134a in systems and compressors designed for R-1 2.


However, Sanden understands the realities of the automotive service markets and consumer preferences. If a retrofit is required, please follow the vehicle manufacturer's published retrofit procedures. Ensure all work done complies with SAE recommended practices as described in J1660 & J1661:

o Repair any problems or leaks before retrofitting.
o Affix labels to the vehicle showing conversion status.
o Observe all safety recommendations.

If an OEM retrofit procedure is not available, Sanden recommends the following procedure:


Sanden Procedure for Conversion from R-12 to R134a

1. If the R-12 vehicle air conditioning system is operational, run it at idle with the A/C blower on high speed for five (5) minutes to optimize the amount of oil in the compressor.
2. Recover all R-12 refrigerant from the vehicle's A/C system. Evacuate the A/C system for at least thirty (30) minutes to a vacuum of 29 in. Hg, using R-12 equipment, to remove as much R-12 as possible from the residue mineral oil. Remove all R-12 service equipment.
3. Remove the compressor from the vehicle.
4. Remove the compressor oil plug and then drain as much mineral oil as possible from the compressor body.
5. Drain mineral oil from the cylinder head suction and discharge ports while turning the shaft with a socket wrench on the clutch armature retaining nut.
6. Remove the existing R-12 receiver-drier or accumulator-drier from the vehicle and discard. Allow as much oil as possible to drain from the A/C hoses.
7. Change any 0-rings on the receiver-drier or accumulator-drier joints to approved HNBR 0-rings; check and replace other 0-rings that have been disturbed.
8. Replace the receiver-drier or accumulator-drier with a new R134a compatible one which contains XH7 or XH9 desiccant.
9. If a CCOT system is being repaired due to compressor damage, or foreign matter is found in the oil drained from the system, this foreign matter must be removed from the system. At this time an in-line filter should be installed in the liquid line. Allow as much oil as possible to drain from the A/C lines when installing the filter. Change any 0-rings disturbed in the installation of the filter to approved HNBR 0-rings.
10. Perform any necessary repairs to the compressor or A/C system.
11. Using the original refrigerant oil quantity specification, add SP-20 or SP-1 0 oil to the compressor (SP-10 for TR, SDV-710, SDB-705, SDB-706 and SDB-709; SP-20 for all other SD compressors).
12. Replace the compressor oil plug 0-ring with an HNBR 0-ring.
13. Reinstall the compressor oil plug. The plug seat and 0-ring must be clean and free of damage. Torque the plug to 11-18 ft lb (15-25 N m, 150-250 kgf cm).
14. Change any seals at the compressor ports to approved HNBR seals.
15. Reinstall the compressor to the A/C system.
16. Disable the R-12 service fittings to prevent any refrigerant other than R134a from being used. Permanently install R134a quick connect service fittings to the A/C system.
17. Connect R134a service hoses and other equipment. Re-evacuate the system for thirty (30) minutes using the R134a equipment.
18. Charge the A/C system with RI 34a. Generally, about 5% (by weight) less than the R-12 charge amount is required. Leak check the system per SAE J1628 procedure.
19. If the A/C system is a CCOT type, which has been repaired due to damage or the discovery of foreign material in the oil drained from the system, run the system for sixty (60) minutes to capture this material in the filter installed in step 9. Recover the refrigerant, remove and dispose of the filter, reconnect the lines, evacuate for at least forty-five (45) minutes, and recharge the A/C system. This step should not be necessary for TXV systems, since the drier is fitted with an internal filter.
20. Check the A/C system operating parameters. The system should function correctly within acceptable limits of temperatures and pressures. This will ensure that the correct amount of R134a has been charged.
21. In extreme circumstances when expected cooling performance cannot be achieved and high discharge pressures are experienced, it may be necessary to add more condensing capacity to the A/C system. An electric fan(s) and/or a larger capacity condenser can be used.
22. Replace all R-12 compressor labels with retrofit labels per SAE J1660 in order to provide information on the R134a retrofit which has been performed.


Basic Sanden R-12 Compressor Retrofit

Specifications for Refrigerant Oil

Retrofit PAG oil amount in fluid ounces (cc)
Model Expansion valve systems
SD-505 3.4 ± 0.5 (100 ± 15)
SD-507 5.5 ± 0.5 (165 ± 15)
SD-508 7.2 ± 0.5 (210 ± 15)
SD-510 No standard
SD-708 4.6 ± 0.5 (135 ± 15)
SD-709 4.6 ± 0.5 (135 ± 15)

Note 1: For long hose, dual evaporator systems, etc. the procedure in the Service Manual should be used.

Note 2: It is recommended that the oil quantity in all cases be reconfirmed after the compressor is installed.

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Works Cited:
Sanden International (U.S.A.), Recommended Procedures for Sanden R-12 Compressors Retrofitted with R134a . Retrieved July 1, 2008, Web site: http://www.sanden.com/support/retro.html
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Modified by 90_Si at 1:30 AM 7/6/2008
Old 07-01-2008, 11:19 PM
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Default Re: Proper R12 to R134a Conversion (90_Si)

WOW NICE!!! this should be sticked IMO... this is going to come in real handy within the next month or two (when i pull my engine to update it and what not)
Old 07-02-2008, 03:15 AM
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Default Re: Proper R12 to R134a Conversion (DCRB)

I agree, this should be sticked to FAQ's
Old 07-02-2008, 08:14 AM
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Default Re: Proper R12 to R134a Conversion (Red_ED8)

im glad someone finally did a write up on this
Old 07-02-2008, 05:58 PM
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Default Re: Proper R12 to R134a Conversion (pandarex)

I pulled out the entire system today I will post pics as well as a write up on the process I went through and will document putting it back together. I will also post more detail about the total F up that the people who worked on it previously did. I know all of the SoCal guys have the great weather and can ditch the A/C, but all of us humid climate guys know we have to have our air. I will also post part numbers and prices of the various things I have added. Right now I am dead tired and grad school calls. So tomorrow evening I will have finished the entire process and will do a full write up with pics along with backstory full of what not to do's (I did not do them, just get to fix them). I will edit the first post with all of this for ease of searching and all that.
Old 07-02-2008, 07:00 PM
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Default Re: Proper R12 to R134a Conversion (90_Si)

I am so glad someone is taking this on. Looking forward to your results. I've tried several times to get an R134 conversion going on various EF/CRX vehicles and have failed every time. Thanks!

Craig

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Old 07-03-2008, 08:05 PM
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Default Re: Proper R12 to R134a Conversion (TunerToys)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TunerToys &raquo;</TD></TR><TR><TD CLASS="quote">I am so glad someone is taking this on. Looking forward to your results. I've tried several times to get an R134 conversion going on various EF/CRX vehicles and have failed every time. Thanks!

Craig

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In some ways it is easier than I thought that it would be, but it is also taking longer than I thought it would. It has taken an extra day. Today I got the system back together with lots of pics, tomorrow morning I will vacuum the system and charge the system and get my dash back in. One other reason I am waiting until the morning (aside from running out of daylight) is that all of the pressure specs are baselined at 80 degrees, so I am hoping to get it done early enough to figure all of that before the temp jumps out of the 80s.
Old 07-04-2008, 11:21 AM
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Default Re: Proper R12 to R134a Conversion (90_Si)

Hi, I spoke to a Sanden Tech support rep about my 91 Honda civic DX. He told me to use Pag oil 150 in my TR70 compressor. This post I think indicates pag 100. Does anyone have more input as to which is correct?
Old 07-04-2008, 12:40 PM
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Default Re: Proper R12 to R134a Conversion (90_Si)

I am also not sure what this means?

" I had my lines rebuilt so they are R134a lines. Because of this I will vacuum my system longer. If you are not having your lines rebuilt and changed then keep within the service manual specs because over vacuuming will remove the mineral oil (what R12 systems are lubricated with) out of the lines, allowing the R134a to escape because the molecules are smaller than R12. "


I thought vacuuming just removes air and water from the system ( The vacuum causes the water to boil and be vacuumed out with the air).It would actually be a good thing if it did remove the mineral oil. The Sanden rep told me it is best if you can get all of the old oil out of your system. He also told me R134a does not mix with mineral oil so it will not carry it through the system, and you don't want more than the specified amount of oil in your system.
Anymore more input would be greatly appreciated. I am in the process of trying to do my conversion.

Old 07-04-2008, 01:00 PM
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Excellent, thanks for the update!

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Old 07-04-2008, 05:37 PM
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Default Re: Proper R12 to R134a Conversion (mschus)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mschus &raquo;</TD></TR><TR><TD CLASS="quote">I thought vacuuming just removes air and water from the system ( The vacuum causes the water to boil and be vacuumed out with the air).It would actually be a good thing if it did remove the mineral oil. The Sanden rep told me it is best if you can get all of the old oil out of your system. He also told me R134a does not mix with mineral oil so it will not carry it through the system, and you don't want more than the specified amount of oil in your system.</TD></TR></TABLE>

I just did the conversion a week or two ago. I have a thread about it a few pages back.

Anyway, my stock compressor was/is still working, so I left it on during my conversion. I was told by Redy-Aire tech support that the oils will not mix so not to worry about it (he actually said the old oil would just sit at the bottom of the compressor and not cause problems). I only used 4 oz. of pag in mine since I didn't do a 'full' retrofit

Old 07-05-2008, 10:14 AM
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Default Re: Proper R12 to R134a Conversion (mschus)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mschus &raquo;</TD></TR><TR><TD CLASS="quote">I am also not sure what this means?

" I had my lines rebuilt so they are R134a lines. Because of this I will vacuum my system longer. If you are not having your lines rebuilt and changed then keep within the service manual specs because over vacuuming will remove the mineral oil (what R12 systems are lubricated with) out of the lines, allowing the R134a to escape because the molecules are smaller than R12. "


I thought vacuuming just removes air and water from the system ( The vacuum causes the water to boil and be vacuumed out with the air).It would actually be a good thing if it did remove the mineral oil. The Sanden rep told me it is best if you can get all of the old oil out of your system. He also told me R134a does not mix with mineral oil so it will not carry it through the system, and you don't want more than the specified amount of oil in your system.
Anymore more input would be greatly appreciated. I am in the process of trying to do my conversion.</TD></TR></TABLE>

Vacuuming will leach anything.. it is a vacuum. It will leach it out of the lines, not boil it out of the system. I can see where my language could have been vague. When I said that it will remove it from the lines I meant it literally. If the Sanden rep told you to do it a certain way, then do it that way. Realize that I am doing a full change over. I am not using a Sanden compressor from Sanden. I am using a new compressor. I pointed out that there are several things one does differently between the two cases.
You are right it does not mix, it creates a barrier in the hose, meant for R12. R12 has larger molecules, R134a will leech out of these tiny pores eventually. This is just something I heard from someone somewhere, so maybe it does not matter but it makes sense to me. If it is harmless in your system, as the Sanden rep said then I would err on the side of caution.

This is just how I am doing it with the system and equipment I purchased. You will find that if you call Sanden, AirPro, Ready Aire, Joe Blow A/C tech or anyone else you will get a different answer for every question. Sanden says to do 90% R134a to R12, Ready Aire says to do 80%, AirPro said 85% (and I think the latter two have the same parent company). I say to go by your system pressure. I followed the manufacturer of my compressors specifications then tweaked it based on my system pressure. You will find things like happend to me happening to you. I had my lines rebuilt. They used 10mm hoses; stock is 14mm. This caused my system pressure to be different and I had to tweak accordingly.


Modified by 90_Si at 1:26 PM 7/5/2008


Modified by 90_Si at 1:29 PM 7/5/2008
Old 07-05-2008, 10:19 AM
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Default Re: Proper R12 to R134a Conversion (mschus)

The manufacturer of my compressor recommended PAG-46 so I used PAG-46. I was told 7 ounces distributed evenly through the system, if the system was completely flushed, otherwise 4 ounces. I would suggest going by the manufacturers specifications.

The following is taken directly off my first post:
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General Unorganized Info
--------------------------------------------------------
- I talked to the tech department at Ready Aire and he said that their rule of thumb is 80% of R12 specification.
- Since the system was completely evacuated and flushed they said to use 7 ounces of PAG-46
----------------------------------------------

I am using a new compressor manufactured by Ready Aire. I am going by their specifications. If you are using a Sanden compressor then I would suggest you go by what Sanden says.
Old 07-05-2008, 10:22 AM
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Default Re: Proper R12 to R134a Conversion (James89DX)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by James89DX &raquo;</TD></TR><TR><TD CLASS="quote">

I just did the conversion a week or two ago. I have a thread about it a few pages back.

Anyway, my stock compressor was/is still working, so I left it on during my conversion. I was told by Redy-Aire tech support that the oils will not mix so not to worry about it (he actually said the old oil would just sit at the bottom of the compressor and not cause problems). I only used 4 oz. of pag in mine since I didn't do a 'full' retrofit </TD></TR></TABLE>

^-------- James and I are doing our A/C systems at the same time in the same driveway. We have found that there is nothing universal about it. My system is reaching the same pressure and cooling strangely identically as his with half the recommended R134a. This is why I suggest that when doing this one tests the PSI in their system. I will go more into all that when I continue to amend the first post as I go along.

-It is basically complete now. All that is left is pictures I will post and the backstory that lead me to doing the A/C myself.


Modified by 90_Si at 2:20 PM 7/5/2008
Old 07-05-2008, 07:02 PM
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Default Re: Proper R12 to R134a Conversion (90_Si)

I am not sure, but all of the research I have done indicates that vacuuming out the system will only remove gases not liquids. When water is placed in a vacuum it turns into a gas (boils). It is my understanding from talking to Mastercool that vacuuming will remove air and moisture but not oil.

90_si, it sounds like your conversion is thorough and should have no problems. But I wonder about mine and James89DX. With residual mineral oil left in the system this would appear to pose a problem. It would seem if you add 4oz instead of the 7oz the system calls for (and the residual mineral is not circulating) that the compressor will be starved for lubrication. Any thoughts on this?

I am seriously considering sticking with r12. I bought a new compressor sanden tr70 for my civic.
The clutch went bad on the old one and I found it just as cheap to replace the whole compressor. I have it in the car but have not yet hooked it up, added oil, or vacuumed it out. I also have the receiver drier, but have not yet installed it. Do you know what the mineral oil used in the system is and where it can be obtained? Thanks

What kind of vacuum are you guys using? I hear the venturi type are not very effective in removing all the moisture, and that the electric ones are the way to go. Also, do you know if there is a difference in the r12 and r34a manifold gauges besides the fittings?
Old 07-05-2008, 10:20 PM
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Default Re: Proper R12 to R134a Conversion (mschus)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mschus &raquo;</TD></TR><TR><TD CLASS="quote">I am not sure, but all of the research I have done indicates that vacuuming out the system will only remove gases not liquids. When water is placed in a vacuum it turns into a gas (boils). It is my understanding from talking to Mastercool that vacuuming will remove air and moisture but not oil.

90_si, it sounds like your conversion is thorough and should have no problems. But I wonder about mine and James89DX. With residual mineral oil left in the system this would appear to pose a problem. It would seem if you add 4oz instead of the 7oz the system calls for (and the residual mineral is not circulating) that the compressor will be starved for lubrication. Any thoughts on this?

I am seriously considering sticking with r12. I bought a new compressor sanden tr70 for my civic.
The clutch went bad on the old one and I found it just as cheap to replace the whole compressor. I have it in the car but have not yet hooked it up, added oil, or vacuumed it out. I also have the receiver drier, but have not yet installed it. Do you know what the mineral oil used in the system is and where it can be obtained? Thanks

What kind of vacuum are you guys using? I hear the venturi type are not very effective in removing all the moisture, and that the electric ones are the way to go. Also, do you know if there is a difference in the r12 and r34a manifold gauges besides the fittings?</TD></TR></TABLE>

I did not say that vacuuming the system would remove oil out of the system. I said that I was told that vacuuming it for long periods of time will leach the mineral oil out of the lines. The oil that is in the hose pores, and that it will stay in the lines, removing what one could call a plug that stops the smaller molecules of the R134a from seeping out of the pores of the line that was designed for the larger moleculed r12. As far as removing something out of the system, it will only remove things that are gaseous.

If you are putting on a new compressor I do not see why you do not flush out the system. Then you know you can add the oil and coolant to the exact specs and know exactly what is in your system.

If you use R12 you will have to take it to a shop and have them do it unless you can source R12 on your own, which is illegal as it is a CFC. If you want to pay what R12 costs and have a certified technician apply then I would say go for it.
Basically if you want to do it yourself you will have to do it with R134a.
Old 07-07-2008, 10:27 AM
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Default Re: Proper R12 to R134a Conversion (mschus)

Originally Posted by mschus
Hi, I spoke to a Sanden Tech support rep about my 91 Honda civic DX. He told me to use Pag oil 150 in my TR70 compressor. This post I think indicates pag 100. Does anyone have more input as to which is correct?
If that's what they told you to use, and your compressor is original, I would use that.

If rebuilt, who rebuilt it? Sanden, or an aftermarket company such as Ready Aire, Transpro, Four Seasons etc?

The compressor 90_Si is using is manufactured Ready Aire, and they specifically recommend Pag 46 to keep the compressor under warranty.

Originally Posted by mschus
I thought vacuuming just removes air and water from the system ( The vacuum causes the water to boil and be vacuumed out with the air).It would actually be a good thing if it did remove the mineral oil. The Sanden rep told me it is best if you can get all of the old oil out of your system. He also told me R134a does not mix with mineral oil so it will not carry it through the system, and you don't want more than the specified amount of oil in your system.
Anymore more input would be greatly appreciated. I am in the process of trying to do my conversion.
Like 90_Si and James already touched base on, R134 will not carry Mineral Oil. In theory, it will just settle to a low point in the system. If you are using your original barrier lines (the rubber suction and discharge lines), you do *NOT* want to flush them, as told to us by Techs at several different companies.

The reason being is that the mineral oil over the years of R12 use will have soaked into that barrier hose and act as a second barrier for R134. If you flush all this oil out of those lines, you may end up with R134 seeping out of the rubber portion because its molecules are so small. Basically, it's another line of defense of losing your R134. If you get lines rebuilt with R134 barrier hose, as 90_Si did, then you will not be hurting anything by flushing the entire system

Originally Posted by mschus
I am not sure, but all of the research I have done indicates that vacuuming out the system will only remove gases not liquids. When water is placed in a vacuum it turns into a gas (boils). It is my understanding from talking to Mastercool that vacuuming will remove air and moisture but not oil.

90_si, it sounds like your conversion is thorough and should have no problems. But I wonder about mine and James89DX. With residual mineral oil left in the system this would appear to pose a problem. It would seem if you add 4oz instead of the 7oz the system calls for (and the residual mineral is not circulating) that the compressor will be starved for lubrication. Any thoughts on this?

I am seriously considering sticking with r12. I bought a new compressor sanden tr70 for my civic.
The clutch went bad on the old one and I found it just as cheap to replace the whole compressor. I have it in the car but have not yet hooked it up, added oil, or vacuumed it out. I also have the receiver drier, but have not yet installed it. Do you know what the mineral oil used in the system is and where it can be obtained? Thanks

What kind of vacuum are you guys using? I hear the venturi type are not very effective in removing all the moisture, and that the electric ones are the way to go. Also, do you know if there is a difference in the r12 and r34a manifold gauges besides the fittings?
Like 90_Si recommends, if you have the means to stay with R12, I would recommend it. R12 is going to run you $30 plus a can, and you need a license to buy it.

Mineral oil can be obtained any place that sells a/c equipment and supplies (pep boys, autozone, shucks, car quest etc). It's all the same for R12 systems - there are not different weights for it (at least I have never seen different weights). When you grab a bottle, all it's going to say is "Mineral Oil for R12".

Make sure you drain your compressor before you add any oil. Most of the time they will come with a packing oil for storage.

James and 90_Si have been using a 3CFM electric pump. I have heard the same thing about the venturi pumps - basically to just stay away from them.

Manifold gauges are the same for R12 and R134 aside from the port adapters at the end. Some brand hoses may only be rated for R134, but the nicer brands will have labeled on the service hose "R12 R134" and will be suitable for both.
Old 07-18-2008, 09:03 PM
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Default Re: R12 to R134a Conversion (90_Si)

I'm just beginning to install a complete ac system in my civic that never had it installed before...and am going to do it the right way also. thought this follwing info may supplement this current thread. A lot of it repeats itself but is worded differently sord of to give this a different dimension. If you think it's the same then I'll simply edit and delete it. There is more ac related info added at the end.

I'm posting the link and pasting it as well:

http://www.gnttype.org/techare....html


Automotive Air Conditioning Retrofitting
Jim Testa - JTesta1966@aol.com
Table of Contents
History of the CFC/HFC debate
What does it mean to retrofit
Component Compatibility
Refrigerants - Alternatives??
Retrofit Procedures
Appendix - Standard, sites with additional information

History
CFC-12 (R12) has been used in cars to let us enjoy a cooler environment on those hot summer days for many years.
In the 70's scientists discovered a hole in the Ozone Layer, and attributed this damage mainly to the use of chloroflourocarbons, which includes CFC-12 used in Automotive Air Conditioning systems.
What is the Ozone?
The Ozone is the atmospheric layer which protects us from the suns harmful Ultraviolet rays, and also maintains a climate suitable for human habitation on the earth. Without it we'd all perish. Over the past few decades, it has been discovered that that certain area of the ozone layer have been compromised. Scientists feel this this damage has been caused in part by chloroflourcarbons, including the chemicals used in mobile air conditioning systems. As a result, recent studies have shown an increase of UV "B" radiation caused by this damage to the ozone layer. If this damage continues, an increase of certain cancers, including skin cancer, cataracts, and reduced crop may result.

Introduced in a worldwide meeting, the Montreal Protocol which is an agreement between 24 countries, to reduce CFC production to 50% of the 1986 amounts by 1988. Since 1987, membership in the Montreal Protocol has increased to over 132 countries. In 1990 this conglomeration called for a CFC phase out by the year 2000.

Additionally, in 1990 the United States Congress, fully supporting the Montreal Protocol, amended the United States Clean Air Act to control production and use of refrigerants needed for all applications, including but not limited to Automotive applications.
Congress had 2 objectives:

To reduce the use of CFC's and HCFC's
To require recovery and recycling of these refrigerants
In 1992 President George Bush ordered a halt in the production of all CFC's by December 31, 1995. After which time, no CFC's can be produced or imported into the United States. This left the US with only inventoried and recovered CFC's for use. The Clean Air Act also implemented an escalating (increasing) tax to be applied to the purchase of CFC's. The result being the high cost of R-12 in the past few years.

Efforts to cope with this ultimate demise of CFC's resulted in many alternate refrigerants containing a vast array of sometimes harmful chemicals to hit the market, advertised as "drop in replacements" for R-12. Currently, there is only one recognized alternative to R-12, HFC-134a, and it is the only refrigerant approved for use by the major car makers.

In 1991, in response to the Clean Air Act and the CFC phase out, manufacturers began to focus their efforts on providing an environmentally friendly alternative to CFC's. They came up with HFC-134a, which contains Hydrogen in place of the chlorine. Additionally, many concerns arose of the effectiveness of converting a previously CFC system to this new refrigerant. We now know this conversion to be a viable alternative in most cases to a CFC based MVAC system. OEM's (Original Equipment Manufacturers) have invested countless hours researching and testing refrigerants and conversion techniques to make a previously R12 system work efficiently with R134a. From this research, OEM's developed specific retrofit kits for converting these systems.

Retrofitting - What is it?
Several SAE (Society of Automotive Engineers) standards define the necessary steps and basic procedures involved in retrofitting MVAC systems. A retrofit in layman's terms is the conversion of a CFC based system to use a HFC refrigerant. With little or no degradation in performance/service life from that of the CFC based system.
Repair vs. Conversion
As long as CFC-12 is available is is legal to service previously CFC-12 bases systems. Once supplies are depleted, the system will have to either be converted to the non-CFC based system, or taken out of service. The extent of the conversion will ultimately depend on the age and condition of the system at the time repair are undergone, and how/where the vehicle is driven. Stop and go driving for example place a high demand on the system and will ultimately affect performance.
HFC-134a offers comparable cooling to CFC-12 when the system has been properly modified, or converted. It makes sense to convert to HFC's before the reserves of CFC's are depleted, especially if a major service is being performed, since repairs will make up much of the cost.
Some of the CFC-12 components will have to replaced for compatibility and to increase performance. Other parts will perform satisfactorily with HFC134a. After properly modifying the system, it should provide adequate performance without compromising the remaining service life of the rest of the original components. However, there is now way to accurately determine the remaining service life of hoses, the compressor, or any other component after it has been in service for a few years.

Work involved comparison Chart
The left column of this *chart lists the steps needed to repair and recharge a typical CFC-12 system, while the right column lists the steps in an identical repair plus modification to a HFC134a system
LEFT COLUMN:
Visual Inspection
Performance Test/Leak Test
Recover Any CFC-12 used
* * * * * *
Clean / Flush the system
Replace Receiver-Drier/Accumulator
Repair with CFC-12 compatable. parts
* * * * * *
Add Mineral Oil
Evacuate the system
Charge the system
Performance/Leak Check system
* * * * * *
RIGHT COLUMN
Visual Inspection
Performance/Leak Test
Recover any CFC-12 used
Remove the Mineral oil
Clean / Flush the system
Install a HFC compatible Accumulator/Drier
Repair with HFC compatible parts
Fit HFC service ports
Add HFC lubricant (PAG/PAE)
Evacuate the system
Charge with HFC-134a
Performance/Leak Check the system
Apply "Retrofitted with HFC-134a" labels
NOTE:For optimum performance, some vehicle will require additional modification.

*Chart taken from IMACA basic retrofit procedures manual


Service with CFC-12 until ???
As long as CFC-12 is available, use of it will be at the discretion of the person making the repairs. When the reserves are depleted, the only alternative will be to use alternate refrigerants.

Existing Components and their Compatibility
Now that you understand the history and basic necessities for a successful conversion, lets look at the compatibility or the various components in existing CFC based systems:

Expansion valves:
Existing expansion devices have shown the ability to accurately meter flow of HFC's after a retrofit. In some cases however, the car manufacturers have recommended expansion devices optimized for use with HFC's to more accurately control flow due to the slightly different cooling characteristics of HFC134a.

Evaporator Pressure Control Valves:
These valves maintain low pressures in the evaporator of approx. 26-30 psi. Since refrigerant temperature is directly related to refrigerant pressure, evaporator temperature can be controlled by evaporator pressure. It has been decided that the existing control valves will provide satisfactory performance, provided it is in good working order.

Evaporators:
The existing evaporator core will provide the necessary heat transfer when the system is converted to use with HFC134a, and should only be changed in the case of a leak.

Desiccant and Driers/Accumulators:
The Receiver Dryer/Accumulator will serve the sane purpose in both systems, however the CFC-12 system uses a desiccant named XH-5 and is NOT compatibly with HFC134a. The HFC will actually eat the desiccant bag, releasing the desiccant pellets through the AC system, damaging other components. In the HFC134a system, you must use a XH7 or XH9 type desiccant, which is compatible with both CFC and HFC based refrigerants. As a side note, I believe all driers/accumulators being sold now are crossways compatible.
NOTE: As a good practice, the drier/accumulator should be replaced after any service to the A/C system required it to be open to the atmosphere for any length of time.

Compressors:
Several engineering studies indicate that existing CFC-12 compressors performed acceptably when the system was retrofitted with HFC-134a. These studies suggest that previous use had conditioned the inner surfaces of the compressor with a chloride film that helps the compressor tolerate the use of HFC-134a. Therefore it has been indicated that the original compressor should perform satisfactorily with HFC-134a. However, if the original compressor cannot tolerate the higher pressures associated with the use of HFC's, a shortened service life will result. If a compressor change is required it is suggested you install a HFC compatible unit. If one is not available, you might check with the component manufacturer to see which replacement compressor might work satisfactorily in your application.

Condensers:
Systems designed for use with HFC-134a generally implement a condenser with increased efficiency. They are generally a rectangle tube type design, sine a rectangle tube will yield more surface area to expose more refrigerant for heat transfer in the same amount of time. A CFC system with limited condensing capacity will more likely produce higher discharge pressures when converted to HFC-134a, especially at higher ambient temperatures and during idling conditions. A technician will have to determine the appropriate course of action to improve system performance if this problem is observed.
Consider the following points:

Missing or broken air dams should be repaired or replaced to increase airflow through the condenser
Ensure the air flowing through the condenser isn't obstructed by dirt / debris. Clean as necessary
Ensure the cooling fan / shrouds are installed and in good condition, and properly aligned in relation to the radiator / condenser.
If a condenser problem has been diagnose to be a post-conversion problem, check to see if there are seals or air directors that should have been installed at time of the retrofit. If not, you may want to investigate whether a higher efficiency condenser is available for the application to increase performance.
Pressure Switches:
The existing high/low pressure switches should perform satisfactorily in use with HFC-134a. If any of these components has failed or does fail, it is recommended to replace with the HFC-134a compatible versions.
NOTE:If the system is not already fitted with a high pressure cutoff switch, it is REQUIRED that one be installed as a safety precaution. Many retrofit kits will include this device if necessary.

Hoses:
It's important to note that all hoses have differences. Hoses manufacturers use different materials and construction varies by manufacturer as well. Some combinations leak more than others, and may not contain the smaller HFC-134a molecule, resulting is more frequent A/C service. Test results indicate that R-134a leaks through walls of non barrier type hose at a slower rate than originally thought. Apparently the mineral oil absorbed by the hose walls somewhat reduces the size of the pores in the hose, aiding in containment of refrigerant. Hose leakage rates have been shown to decrease with use of the newer synthetic lubricants. What does this mean?? Simply put, if the integrity of the existing hose material and the associated hose couplings are intact, the existing hose may be used. If the hoses are to be replaced due to leakage during service, it is recommended barrier type be used, with the appropriate fittings.

O-rings,Gaskets, and Seals
Heat, operation, and age will take their tolls on sealing. Keep in mind that disturbing o-rings on one side of a component may cause another side to leak. These problems are not new to automotive service. Under normal conditions, it is not necessary to change these components during a retrofit to HFC-134a, unless they are leaking, a component has been replaced, or the manufacturer has determined the sealing material is not compatible with the new refrigerant/oil. The two most common gasket materials found to be compatible with the new refrigerants are: high grade neoprene, and Hydrogenated Nitrile Butadine Rubber (HNBR), and are in use by many automobile A/C manufacturers. To avoid using the wrong seals for an application, it is wise to keep the different variations separated from each other. Additionally the newer type o-rings are usually a different color than normal ones.

Service Ports:
The existing ports should be checked for o-ring wear and leakage. It is advisable to change the schraeder valve cores to a type compatible with HFC-134a. New HFC134a service ports will be utilized in a retrofit, and depending on manufacturer design, may or may not use existing schraeder valves to aid in sealing.

Lubricants:
Lubricants seem to be an issue of confusion. Mineral oil, which has been used in CFC-12 systems since the dawn of time are NOT compatible with HFC-134a. Two new synthetic oils have been developed for use in HFC based systems. Polyalkaline Glycol (PAG) and Polyol Ester (Ester). Both perform well in HFC systems and are commercially available. It is up to the discretion of the compressor manufacturer or the retrofit kit manufacturer which oil you'll use.

Refrigerant Issues
The EPA keeps a listing of new acceptable refrigerants on their Web site. But they do go on to say that not all of the refrigerants are suitable for use in automotive applications. It is advisable to ask your manufacturer, service technician, or refrigerant manufacturer if the particular refrigerant will work in an application. Be sure the refrigerant you are using is meant to be a substitute for CFC-12 and NOT for HFC-134a, as introducing other refrigerants WILL void any warranty you have, and quite possibly damage the system. Vehicle manufacturers recommend ONLY HFC134a for retrofitting because it is the ONLY refrigerant that meets manufacturers' performance and durability requirements. It is widely available, inexpensive, and you will be able to obtain service on a HFC134a system almost anywhere in the world.
Beware of Flammable Refrigerants
It is ILLEGAL to replace CFC's with a refrigerant consisting of pure propane, butane, or any other flammable substances. Vehicles presently designed for use with CFC-12 should NEVER be repaired with a flammable refrigerant. Think what would happen if you had a evaporator leak and lit a cigarette????

Over 15 states strictly prohibit the use of flammable refrigerants no matter WHAT refrigerant they are replacing.
Automobile Insurance companies may not protect owners against liability for damages as a result of using flammable refrigerants.


A word on replacements other than HFC-134a
A number of refrigerants other than HFC-134a have been listed by the EPA as acceptable under its Significant New Alternatives Policy (SNAP) program, or are under SNAP review. The SNAP program evaluates substitutes ONLY for their effect on human health and the environment, and not for performance or durability. NONE of these refrigerants have been endorsed by the OEM's for use in motor vehicles, and few have had extensive testing in a wide range of vehicle models. Additionally a problem with using one of these alternatives is that they are not readily available in all parts of the country. While some of these manufacturers of these refrigerants claim they are direct drop ins, there is NO SUCH THING as a refrigerant that can be dropped in place of or along with existing CFC-12. For more information on the SNAP requirements on which alternatives have been reviewed, accepted, or deemed unacceptable by the EPA, call the Ozone Hotline number at 1-800-296-1996 and ask for a copy of "Choosing and Using alternative Refrigerants in Motor Vehicle Air Conditioning".
On a side note: Any alteration from a CFC-12 system MUST be labeled as such, including special service ports. If you do decide on a alternate refrigerant, make sure you can have it serviced. If the system fails far from home, you will NOT be able to get it serviced unless the shop you go to has equipment specifically for that type of refrigerant. Additionally, if a component fails under warranty, most companies will NOT honor the warranty as there Are no approved substitutes for CFC-12 or HFC-134a.


The current retrofit procedures:
The retrofit basically is a straightforward deal.
Test system for leaks
Repair leaks
Remove and drain mineral oil from compressor
Flush evaporator and condenser
Replace Accumulator / Receiver-drier
Install HFC-134a service fittings
Install proper amount and type or refrigerant oil (will be in kit)
Evacuate system at 29"hg for a minimum of 30-40 minutes
Charge system with 80%-90% of CFC-12 capacity
Leak test system
Performance test system

Appendix
Information gathered by IMACA and EPA. Compiled arranged and written by Jim Testa.
More information can be obtained at the EPA's web site: http://www.epa.gov
The MACS web site: http://www.macs.com and the IMACA web site: http://www.imaca.com

THE END ^

GOOD TIP:

Getting the refrigerant (Freon) charge is the most important and hardest thing for you to get correct. The best way to tell is by hand. Find out which aluminum tube that is connected to the compressor is the low side. The low side aluminum tubing that enters the compressor is what you feel. "BE CAREFUL NOT TO GRAB THE HIGH SIDE ALUMINUM TUBE THAT EXITS THE COMPRESSOR AS IT CAN BURN YOU" Keep adding freon while you feel the tubing. You will keep adding freon until the aluminum tubing gets cold and sweats.

The a/c will be correctly filled when the aluminum tubing that connects to the compressor will be cold and sweating. Like an ice cold soda can. The compressor itself should NOT sweat!! If you overcharge the system the compressor will sweat and by now you should know that just the low side tubing entering the compressor should be sweating. Now you can only feel the aluminum part of the tubing not the black rubber.

got it from here: http://members.tripod.com/~jbabs714/autoac.htm

I will be installing this ac inline filter as well:

http://www.ackits.com/TSI/Inline.pdf

from here: http://www.ackits.com/c/inline....html

I'm trying to find out how can you tell what a large capacity condenser looks like so I won't get lied to someone trying to sell me an old type

this is interesting but don't think it is it:

http://www.ackits.com/merchant...allel

any thoughts?




Modified by steeltoe at 10:13 PM 7/18/2008


Modified by steeltoe at 10:14 PM 7/18/2008


Modified by steeltoe at 10:16 PM 7/18/2008
Old 07-21-2008, 12:41 PM
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So, steeltoe, how'd the conversion go?

I spent hundreds of dollars on doing my conversion to r134a the 'right way' and I'm so unbelievably unhappy at its performance I'm actually now in the process of reverting back to r12.

I guess it's a learning lesson. All the proper instructions, technique, etc. won't make up for the fact that retrofitting r134a into an r12 car just isn't going to cool as well, hands down.
Old 07-21-2008, 02:07 PM
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well I'm still collecting the right parts...I ordered a rebuilt sanden from airproair.com listed on sanden's where to buy page. then afterwards is when I learned that it's proper to use a compressor designed only to be used with 134a oils...thinking of selling that rebuilt one when it comes in...and buying a new 134a compressor.

as far as condensers go you need to have the 134a compatible one and it's definately the Parallel Flow Condensers listed on the link in my previous post. I just don't trust anyone selling condensers and I would need to verify and double check to make sure that it is...I keep thinking that there are a million R-12 condensers that suddenly were outdated and these part stores are trying to sell em off first, am I being paranoid..I don't think so but it's just the way the real world works. was your condenser an absolute parallel flow/true high capacity one? the proper condensers seem to be the most important change to a 134a system.

http://www.ackits.com/merchant...allel

the above link seems to have universal condensers that may not bolt right up to the oem ac lines...I'm in the process of finding a Parallel Flow Condenser that's made to fit the oem ac lines and I can't seem to locate any...if they're actualy made for our old cars to begin with, I doubt it but won't stop looking just yet. I'm starting to lean towards them not being made and this universal one is the answer which means I'm gonna have to chuck away the oem lines and get universal ac lines fitted in. I've seen a few places selling universal ac lines made for 134a applications...that may be my solution but harder to do. I'm gonna keep trying to locate a parallel flow cond made for 88-91 civics in the meantime I'm gathering other 134a compatible components including the drier, yes the drier must be 134a compatible, some are made for both the R-12 and 134a but I don't buy that...134a all the way or nothing.

I'll update this with my final outcomes...at my pace it may not be till the end of the summer or maybe more but who cares as long as I give it my best shot.

I'm curious what actual components did you use in every part of your ac system...please detail it for me..thx!





Modified by steeltoe at 3:14 PM 7/21/2008
Old 07-21-2008, 02:10 PM
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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by James89DX &raquo;</TD></TR><TR><TD CLASS="quote">

I guess it's a learning lesson. All the proper instructions, technique, etc. won't make up for the fact that retrofitting r134a into an r12 car just isn't going to cool as well, hands down. </TD></TR></TABLE>

I always thought that this was common knowledge. Google 'r134a', and see what you get.

I guess it's just a question of what's more important to people, a cool *** while we are driving our cars in 2008 or a fried *** in 2038?

As a refrigerant r134a blows big time. I had it done to my 1990 CRX years ago.
r134a is 'supposedly' great for the environment. We shall see though, the jury is still out. But it's more 'ecologically friendly', than R-12, well at least as of 2008 it is.
Old 07-21-2008, 02:44 PM
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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4crx4me &raquo;</TD></TR><TR><TD CLASS="quote">

I always thought that this was common knowledge. Google 'r134a', and see what you get.

I guess it's just a question of what's more important to people, a cool *** while we are driving our cars in 2008 or a fried *** in 2038?

As a refrigerant r134a blows big time. I had it done to my 1990 CRX years ago.
r134a is 'supposedly' great for the environment. We shall see though, the jury is still out. But it's more 'ecologically friendly', than R-12, well at least as of 2008 it is. </TD></TR></TABLE>

Well, yeah, it is 'common knowledge'. I knew that ahead of time.

My whole thing is that I took the time to do it right. Most people who convert just put new fittings on it and top it off with r134a then complain that it sucks.

I did everything 100% by the book, and even spent a couple hundred more dollars and did everything that was 'recommended' to do (i.e., high output electric fans on condenser).

I was looking into getting a custom huge condenser made but then realized that's a retarded thing to go out of my way to do (bad enough I wasted money on electric fans) for such a lousy refrigerant. Although people who live in not-so-hot climates or climates that occasionally get hot but with low humidity may not notice as much as me being in Texas.

[It's convenient that r12 suddenly became bad for the ozone when DuPont's patent ran out and when NASA started getting huge funding for research contingent on CFC's being the 'big issue'

To the best of my knowledge no tracer tests have ever actually been performed proving that terrestrial chlorine gets transported to the stratosphere. Everything is based on computer models. It would be EASY to tag some CFC and see if it actually ends up in the stratosphere. That is, if any agency wanted to ACTUALLY find out. But I digress.]


Modified by James89DX at 4:02 PM 7/21/2008
Old 07-21-2008, 02:57 PM
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Default Re: (steeltoe)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by steeltoe &raquo;</TD></TR><TR><TD CLASS="quote">well I'm still collecting the right parts...I ordered a rebuilt sanden from airproair.com listed on sanden's where to buy page.
Modified by steeltoe at 3:14 PM 7/21/2008</TD></TR></TABLE>

Small world, I actually originally bought all my parts from Air Pro. I live about 5 miles from those guys. To be honest, I'm surprised they're not more knowledgeable, helpful and really surprised they have cruddy parts (virtually all their stuff is Four Seasons brand which you can buy cheaper virtually anywhere). When I was first gathering parts for my swap, I went up there to buy everything.

First trip I got home and realized they sold me the wrong expansion valve (threads were wrong). I go back up there and the lady (don't remember her name, she's Hispanic and very hard to understand) just about stripped my evaporator threads trying to get it on. Eventually she went to the back and came out with a different expansion valve on it. So I go home, ready to put it all back together.

Then I realize the evaporator doesn't fit. The tubes are all wrong and wont fit in the black evaporator box. I go back and tell/show Troy (who by the way calls you "man" about 10 times a second) and he blabs about "making it fit". Then he suggests I cut up my evaporator box to fit. I tell him I'm not interested in cutting up the box and then he tells me he's got a guy who can "make it fit".

At that point I just want to return it all, get a refund, and start fresh somewhere else. He tells me that's okay but he'll have to charge me a restocking fee because I put the expansion valve on the evaporator and that they'll "have to try to take it back off". So then I'm like "uhhh, no, your fellow employee is the one who wasted 30 minutes of my time trying to make the wrong expansion valve fit, then she went in the back and when she re-appeared this current expansion valve was hooked up".

Anyway, I finally got a refund. I ended up piecing together all my parts from PepBoys, O'Reillys, and NAPA.
Old 07-21-2008, 03:17 PM
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Default Re: (James89DX)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by James89DX &raquo;</TD></TR><TR><TD CLASS="quote"> All the proper instructions, technique, etc. won't make up for the fact that retrofitting r134a into an r12 car just isn't going to cool as well, hands down. </TD></TR></TABLE>
Thats odd, mine blows 38 degrees out of the vent and I didnt do half of the stuff on that list. 1st of all you dont have to drain all of the original oil out of the system but by doing it you will be able to put more r134 into the system. To the OP: Converting the lines to r134a huh, I've never heard of that one, kinda sounds shady to me. Any pics to see what exactly they did. Side by side the rubber lines from say an EG/EK are made in the same fashion as those of an EF. Early EG's also came in both r12 and r134 with minimal system changes, but thats neither here nor there. I agree 100% with removing the evaporator and cleaning it, (but dash removal isnt necessary. Even when you install A/C on honda's that didnt come with them), replacing o-rings for good measure, and sucking down the system for a longer amount of time than usual. I'd also replace the receiver/drier (I didnt read that far into the original post to see if that was mentioned, but that sole piece has a great deal to do with A/C performance. Replacing fans is a waste of time and money IMHO.
To those of you who are unhappy with the performance of your retrofitted car, Did you check the condition of your condenser? If air is unable to adequately flow through it, your interior will not get cold. Also I recommend cleaning it with water (Pressure washed) since years of crap will clog it as well as get between the radiator and the condenser limiting airflow. If you put a thermometer in the vent and wash down a plugged condenser you can watch the temp drop at least 5 degrees on a car. It may not sound like much, but the difference between 40 degrees out of the vent (which is spec on a Honda) and 50 degrees is night and day. Also make sure your heater valve works properly since hot coolant=warm air. The cables that attach them do come out of adjustment and is a common problem on older cars. As far as the 80% of r12 spec, it is much more accurate to charge by line pressure based on ambient temp. By doing so, you'll also be able to guage vent temp without even getting in the car. You guys may not have realized that the r12 system in older cars is designed to hold much more refrigerant than that of newer honda's. Them getting cold enough or them not getting cold enough is usually do to poor maintanance ( I dont mean to step on toes with that comment either) Sanden compressors are notorious for leaks at the front seal, and o-ring replacement is crucial. The fiting at the top of the condenser (behind the left side of the radiators support loosens up on its own too so be sure to check that one first as well as all of the other ones. It gets too hot some places to not know all of these things up front. Failing expansion valves will cause low side pressure problems (too low) on cars that are fully charged and HUMIDITY in the air makes it even harder for air conditioners to work properly. Good luck.


Modified by soulpwr at 4:24 PM 7/21/2008
Old 07-21-2008, 04:02 PM
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Default Re: (soulpwr)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by soulpwr &raquo;</TD></TR><TR><TD CLASS="quote">
To the OP: Converting the lines to r134a huh, I've never heard of that one, kinda sounds shady to me. Any pics to see what exactly they did.

I'd also replace the receiver/drier (I didnt read that far into the original post to see if that was mentioned, but that sole piece has a great deal to do with A/C performance.

If air is unable to adequately flow through it, your interior will not get cold. Also I recommend cleaning it with water (Pressure washed) since years of crap will clog it as well as get between the radiator and the condenser limiting airflow.

The fiting at the top of the condenser (behind the left side of the radiators support loosens up on its own too so be sure to check that one first as well as all of the other ones. It gets too hot some places to not know all of these things up front. Failing expansion valves will cause low side pressure problems (too low) on cars that are fully charged and HUMIDITY in the air makes it even harder for air conditioners to work properly. Good luck.

Modified by soulpwr at 4:24 PM 7/21/2008</TD></TR></TABLE>

Air-Pro rebuilt his A/C lines. Yes there's pictures. I'll post them later on if you're interested. The new lines actually say 'r134a' on them.

I can't vouch for anyone else but both 90_si and I both put on new driers.

I also put a brand new evaporator on mine (that's actually the original cause of my A/C quest - my evaporator had thick tar-like stuff on it that would not clean off and I had absolutely no air blowing from the vents)

I noticed that too about the top line on the condenser. When I was trying to source a good condenser for mine from the junkyard I noticed on every single car I checked out that that fitting was loose. I'm assuming it gets worked loose by radiator movement (whether by getting work done and just from movement over the years).

Not sure I agree with you about the condenser fans. You'll notice most new cars that come factory with r134a have large pusher fans on the condensers. Manufacturers wouldn't do that unless it improved r134a cooling ability at idle.

*edit* Also, you said it blows 38 degrees at the center vent. Mine also blows about 40 at the center vent, at say, about 8 pm on a highway cruise. I live in Dallas. It looks like you're in California - so it's all relative. I would bet it's not quite as hot there and not nearly as humid. Does yours blow 38 degrees at the center vent sitting on the freeway in stopped traffic on a 100 degree day? That's my problem, sitting idle in 100 degree heat on a humid day. The r134a just doesn't cut it. It blows 80 degree air out of the center vent.


Modified by James89DX at 5:15 PM 7/21/2008

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