1992 Accord R134a retrofit

[Chris142]

You can try it on R134a and see if you like it. Use fast evaporating AC solvent to flush out everything except the compressor. Use Ester oil to flush the compressor.

Change the dryer. Replace all the Original Black O-Rings with the Green ones for R134a. Don't forget the big O-Ring on top of the compressor where the manifold goes. Most auto partsstores will have an O-Rinmg kit for your car so you don't have to go searching around for O-Rings.

Use 85% of your R12 amount. If it held 32oz of R12 you want to use no more than 28oz of R134a.

Use 3.5 oz of Ester oil per pound of refrigerant. I'd put in 7oz myself. An extra ounce won't hurt the cooling but will help with compressor life.

Pag oil should not be used in a system that contained R12. Always use Ester plus if you don't like the R134a you can use R12 with Ester if you need to go back to R12.

Make sure that your heater valve is not allowing hot coolant into the heater which will warm up your AC vent temps.

 

[Cutehumor]

Originally Posted By: exranger06
Originally Posted By: MarkM66
Mechtech2 is right.

Business's are regulated by government and or state agencies, as in OSHA, EPA, DOT, RCRA, DNR, etc, etc. Civilians/residential is NOT.



Oh. My. God. Don't. Freakin. CARE!! Ok since you guys are practically INSISTING I vent it myself, I will! Would that make you happy?!


take a chill pill bro

 

[MarkM66]

Originally Posted By: exranger06
Originally Posted By: MarkM66
Mechtech2 is right.

Business's are regulated by government and or state agencies, as in OSHA, EPA, DOT, RCRA, DNR, etc, etc. Civilians/residential is NOT.



Oh. My. God. Don't. Freakin. CARE!! Ok since you guys are practically INSISTING I vent it myself, I will! Would that make you happy?!


I don't care what you do with it.

But some people may appreciate accurate information, whether or not it pertains to your car.

 

[lexus114]

Originally Posted By: Cutehumor
Originally Posted By: exranger06
Originally Posted By: MarkM66
Mechtech2 is right.

Business's are regulated by government and or state agencies, as in OSHA, EPA, DOT, RCRA, DNR, etc, etc. Civilians/residential is NOT.



Oh. My. God. Don't. Freakin. CARE!! Ok since you guys are practically INSISTING I vent it myself, I will! Would that make you happy?!


take a chill pill bro


yeah really.

 

[Papa Bear]

Found this on a Honda-tech site ...

"1. The ac units on the pre 98 accords have very little reserve cooling capacity (I have a '94 accord with r134a) and I would not recommend retrofitting if you can make the following repairs:

1. replace all hoses with barrier hoses (this will precent the R-12 from escaping through the hoses over time).
2. replace all of the o-rings with the newer type that can handle R-134a (in case you want to change it over).
3. Replace accumulator/dryer.
4. pressure test system for leaks (IE put on a vacuum pump for 12 hours).
5. Fill with proper amount of R12.

If you are going to fill it with R-134a you will need to:

1. Take the compressor off and drain all of the oil out of it
2. Chemically flush the compressor to remove all traces of the R-12 based oil refill with proper pag oil suitable for use with r-134a. (I'd just buy a new compressor that will work with R-134a)
3. Chemically flush the rest of the system to remove any traces of R-12 and compressor oil
4. replace the Accumulator/Dryer with one that is suitable for use with R-134a
5. replace all o-rings with ones compatible with r-134a
6. pressure test reassembled system by holding it on a vacuum for at least 12hrs
7. refill with the proper amount of r-134a

Although most ac parts can handle the higher pressures used by r34a, some older parts may fail.

R134a is a weak coolant and require a higher working pressure to get the same colling effect as R-12 and it's reserve cooling capacity really sucks."

Hope this helps....

 

[exranger06]

Question on the adaptor fittings. Do I have to remove the valve core on the low side before screwing on the adaptor? The adaptor has a valve core installed.

 

[rshaw125]

Venting? new fittings? Why? Top up with Enviro-safe. It's compatible with everything. That's the beauty of it. My old van lost some charge after 12 years. I put in a can that had some seal conditioner in it.
Why make something that is pretty simple and cheap so complicated and expensive??

 

[Texan4Life]

Originally Posted By: exranger06
Question on the adaptor fittings. Do I have to remove the valve core on the low side before screwing on the adaptor? The adaptor has a valve core installed.

no you should'nt have to. the little thing sticking out of the back is suppose to press the old valve in as you screw it on. Thanks for the pics that helped.

as for as the difference between parallel flow and tube and fin style. The tube and fine is one long tube that starts on one end and is run back and forth in a S shape to make the rectangle.

Parallel flow has multiple straight tubes (and usually use rectangle shaped tubes) that run from one side to the other. and the flow is from on side to the other through all of the tubes at once instead of having to snake through one long tube.

 

[Texan4Life]

Originally Posted By: exranger06
It has an expansion valve and it has only one pressure switch on the high side of the system. As far as I know, it's not adjustable.
This is what my condenser looks like, I assume this is a tube and fin design? It's actually the same style as the one on my Ranger and Explorer, which both have R134a.

That's odd looking. the tubes look like parallel flow to me, yet the hose end are on the same side.

I would bet it is parallel flow.. tub and fin looks old school and the fin density usually sucks.

---

I don't have much experience with expansion valve systems. The pressure switch on the high side is probably a high pressure cut off switch. There is no sensors on the low side?

 

[exranger06]

Time for a little update. I finally got around to working on this. I'm not close to being done, but I made some progress, sort of. I got all the R-12 out of the system and started disconnecting some of the lines. I tried disconnecting one of the lines on the condenser and the bolt snapped.

I guess that's what happens when steel stays threaded into aluminum for 19 years. Looks like I'm spending tomorrow afternoon replacing the condenser..

Because of this (I had a feeling disconnecting lines that old might cause problems) I will not replace ALL of the O-rings in the system. There are about 12 O-rings total, and I already have 7 of them out. The rest I will leave alone. If I get a leak in the future, I'll know where to look and will replace them as needed. Until then, they're staying put.

 

[kasedian]

Because of this (I had a feeling disconnecting lines that old might cause problems) I will not replace ALL of the O-rings in the system. There are about 12 O-rings total, and I already have 7 of them out. The rest I will leave alone. If I get a leak in the future, I'll know where to look and will replace them as needed. Until then, they're staying put.[/quote]

New ones can leak just as easy as the originals. Maybe even more-so.

 

[RH+G]

Thats a serpertine condenser. Thats better than a tube and fin but not as good as a parallel flow.

 

[exranger06]

Another update: Got the new condenser in. Removed the compressor to drain the oil out of it, but hardly anything came out...

Added about 3 oz of Ester oil to it and reinstalled. Removed drier, drilled hole in bottom to see how much oil would come out, and nothing came out...

I guess most of the oil came out when it was evacuated?

Also I think I have a small hole in the radiator, perhaps from me trying to wrestle the fan back in the car.

Oh well, it was looking pretty beat up anyway. Ordered a new one today, should have it installed tomorrow. Stay tuned!

 

[ltslimjim]

^Hang in there, great effort!

 

[Hootbro]

Originally Posted By: mechtech2
Laws apply to shops, NOT civilians.


Unless you are a member of the military armed forces, everybody else is a "civilian".

 

[exranger06]

So I just looked up in the Haynes air conditioning book that the total system oil capacity is 3 to 4.1 oz, and like I said before, I had poured about 3 oz into the compressor before reinstalling.

I could have sworn it was about 7 oz total capacity. I think I will remove the compressor again and drain out the oil and add only 1-2 oz to it. The rest will go in the drier. I wouldn't want to hydrolock the compressor.

 

[exranger06]

So I'm pretty much all done but I have some questions. I finally got everything installed, vacuumed it down for a little less than an hour, and recharged. I used the specs in the Haynes AC book and charged it until the high pressure side was 200 psi and the low side was about 30 psi. (the book said 200 psi for high side and between 25-35 psi low side) BUT- do those pressures apply to R134a too, or just R12?? I got a vent temp of about 50 degrees, a little higher than I was hoping for, but the car was just idling in the driveway and it was VERY humid. The Weather Channel said it was 85 degrees outside and "feels like" 90 degrees. You should have seen all the water pouring out of the evaporator drain tube. The sight glass on the drier still looks a bit foamy, but I don't think I should add any more refrigerant. I'll be driving the car to work tomorrow and will report the vent temps at highway speeds. I need to replace the upper radiator hose tonight before I can drive it though.

 

[exranger06]

One thing to add: Haynes book says refrigerant capacity is 2-2.1 lbs of R12. Common rule of thumb is 85% capacity for R134a right? That makes it about 1.75 lbs (28 oz) of R134a. So far I added about 20 oz. Also, based on some recent research, R134a operates at higher pressures. That info, combined with the fact the sight glass is foamy leads me to believe I need to add some more refrigerant. Anyone agree/disagree?

But from what I've read, it would perform best with the low pressure side around 25-27 psi. If I add more refrigerant, wouldn't that pressure go up and performance decrease?

Need some help here!

 

[artificialist]

Originally Posted By: exranger06
One thing to add: Haynes book says refrigerant capacity is 2-2.1 lbs of R12. Common rule of thumb is 85% capacity for R134a right? That makes it about 1.75 lbs (28 oz) of R134a. So far I added about 20 oz. Also, based on some recent research, R134a operates at higher pressures. That info, combined with the fact the sight glass is foamy leads me to believe I need to add some more refrigerant. Anyone agree/disagree?

But from what I've read, it would perform best with the low pressure side around 25-27 psi. If I add more refrigerant, wouldn't that pressure go up and performance decrease?

Need some help here!

R-134a refrigerant will always have bubbles visible in the sight glass. Anyway, I have always been told 30 PSI on the low side is ideal.

 

[exranger06]

OK this is my FINAL update: Got the rad hose replaced last night and took the car for a drive. I was getting vent temps of about 41 degrees!

I drove it work this morning and kept the AC on the LOWEST setting for the last half of the drive. By the time I got to work, I was freezing! Temps stayed consistently at around 40 degrees, sometimes dipping down to 38 degrees. I'm officially declaring the retrofit a success!