Community Forums

levoyb · 04-01-2010, 03:55 PM

Have a 1991 pace arrow m/h. Dash air was not working. Got it out of shop today. Now blows, but not very cold. Dumb question I know, but do I raise the hood to get to the a/c lines or go through the engine access inside? I assume I can charge the system myself. Any help would be appreciated.

TXiceman · 04-01-2010, 06:22 PM

First welcome to iRV2. Next, I have been in the refrigeration business for 40 years and any refrigerant can be dangerous if not treated safely.

In 1991 they were switching over from the old R12 (Freon12) to the newer R-134a. I do not know if your coach has R-12 or R-134a. There should be a sticker if it is still there telling you how much and and what type of refrigerant is used. If the tag is gone, an A/C technician can tell you which one it uses.

R-12 is not sold in this country any longer. If it has R-12, you will need to reclaim the refrigerant per EPA procedures. Then you need to find the leak as you may have leaked oil as well as refrigerant.

Many shops will want to convert you to R-134a which can be a major expense for an older coach. You may need to change elastomers and some other components as well as the oil in the system if it is done correctly. There are several drop in blends on the market that will work with your current set up and oil...one has the trade name of Hot Shot. Some of the shops will try scare tactics to get you to do it the expensive way and do the full conversion. Hot Shot and the other blends have a small portion of the mixture as propane. It is not dangerous as it is used, so tell them to learn something about what they are talking about before opening their big yappers.

If you have R-134, it still needs to get the leak fixed first and then recharged. You can by a charging kit and refrigerant from WalMart and any auto store. If you don't do it right, you can cost yourself a lot more money than you are trying to save.

Ken

Chuck 1935 · 04-01-2010, 06:57 PM

If you still have some cool air you should be able to get away with a small recharge whether R12 of R134. The recharge fittings for R12 and R134 are not interchangeable so you probably won't have a problem. The recharging set up for 134 is avaiable at all automotice stores. The R12 recharging fittings are harder to come by. You can purchase the Freeze 12 at Sherco Auto Supply although it can be purchased under a number of 12 names on the internet.

levoyb · 04-01-2010, 07:57 PM

Many thanks. We're trying to get away Monday morning, so I may just have to run the roof air right now. Which is what we did last year due to another a/c problem and it wasn't too bad. I do appreciate your help.

Wizard · 04-02-2010, 06:45 AM

One other thing to check is a problem I had.

On a warm day, crank the engine, turn air on full and check temp of air from registers. After the engine warms up, check temp again.

If there is a difference, you could have warm air mixing. My blend door was not closing all the way due to a vacuum leak at the solenoid.

Just one other thing to think about on an older unit.

levoyb · 04-02-2010, 11:01 AM

Thanks again, my blend door was not closing at all, which is why I had it in the shop.(for 3rd time!) It appears I need r12 coolant. Any suggestions as to where to find? I guess I'll call Sherco as someone mentioned them. Thanks again

jcthorne · 04-03-2010, 06:42 AM

Real R-12 is readily available in 12oz cans on Ebay. You will be far ahead using the real mccoy than any of the substitutes.

If your shop is certified for the work, R-12 can still be purchased both new and reclaimed in the US. It is expensive but the price peaked about a year or two ago and is actually falling as very few vehicles are left on the road using it.

TXiceman · 04-03-2010, 07:59 AM

You might want to read this information on R12 and its replacements.

December 31, 1995 ended the production and retail sale of new R-12 in the United States. The refrigerant can be continued to be used in existing equipment using existing refrigerant supplies and reclaimed refrigerant. There have been some massive fines on companies that were illegally bringing new R12 into the US as well as the unlicensed sale of R12. R-12 is to handled by licensed technicians.

HERE are some alternates to use for R12 under SNAP.

The best advice is to change the system over to a suitable substitute blend as identified by SNAP. Trying to just dump in an unknown blend that has 12 in the name will be taking a chance. The refrigerants like Freeze 12 or Hot Shot are blends and may or may not be compatible with R12. Mixing theses blends with R12 will have unpredictable results as to the properties of the resulting mixture.

I still have several unopened cans of original R12 (not for sale). I would be very careful buying "R12" from Ebay sellers unless you are sure of the product and the sellers.

Ken