A/C was working fine last winter and suddenly the compressor will not come on for any command. The fuses are all good and I have swapped relays around(not sure which is the a/c)pushed and prodded the dash switch, jiggled the ignition and just about everything else I can think of. Any thoughts?
1985 380SE 199,910 miles

Did you check the freon level? Do a search in this site. There are some discussions on AC matters.

I had same problem and it turn out to be the dash board switch. If you had a ohmmeter you can check it for proper operation.

No A/C
 

I just had a multitude of problems with my 300CE. One of them the same as yours. They all went away with getting my Freon recharged. Unfortunately Freon is expensive now. Cost me $ 200 for the service but the end result was worth it.

Good luck

Eric

Thanks guys, I did get an additional lb. of r-12 put in last fall. I don't think this could have influenced the problem but maybe I have developed a leak because of over pressure. I will take it in to determine if indeed there is any freon in the system.

El MIquil
 

El, there are a number of conditionals that must be satisfied before the A/C will perform.
The most common being low on refrigirant.
Before you have a 12 oz. can of R-12 costing $40.00 added to be able to test your A/c; do yourself a favor and go to a K-Mart Store and for $40.00 get a R-134A conversion kit.
If you follow the directions/instructions you can have an A/C unit that will cool as well as the R-12 gas did.
In addition to the kit direction is to rent a vacuum pump and a manifold gage set, I'm sure your local rentall has them.
Pump down your unit and hold it at vacuum for a couple of hours to dry out the inside of your A/C.
First thing I do is add the 8 1/2 oz oil charge to have enough pressure to close the safty switches. This oil blends with the R-12 oil and makes them better.
Follow the instructions and you will be home almost free.
One addition gage I purhased is the capacity/level tester that tells you when you are low, high or just right on refrigirant level.
Go for it!!!
Happy Easter to you and your's
Happy Trails Beep Beep from Houston!!!
Donald, El Cheapo

Thanks Donald. I have been considering doing just as you said. R-12 is getting harder to find and very expensive to boot! I can do the R-134 myself. I bet I have a leak somewhere. Now to find it!

ElMiguel
 

You're right Chico, but you can't fing a leak unless there is somrthing to leak. Considerring R-12 at $40.00 for 12 oz. I would rather make the conversion and use the R-134A for $5.99 for the same size.
The leak may be so small that you may wait until something major need repairing then fix the leak.
Always look ahead and try to kill two birds with one stone.
Good luck with your effort, you will over come.
Happy Trails Beep Beep from Houston!!!
Donald, El Cheapo

Righto! Thanks for the suggestions.

El M
 

No problemo, let us know how it all turns out.
Happy Trails Beep Beep from Houston
Donald, El Cheapo

Freeze 12 as R12 sus
 

Has anyone on this list heard of Freeze12? I heard of it and it was recommended by others on a Volvo list I also subscribe to. Those who have used it say it is about double the cost of 134a, but mixes well with R12 and doesn't require any conversion. It is found on http://www.freeze12.com and I'm going to try it.

Mike

I had some of this Freeze 12 that I was going to put in my Ford F-150 but decided to convert it to R-134 because it was cheaper. Evidently it will mix with R-12. I gave the Freeze 12 to my dad who put it in his Cadillac. No problems that I know of.

Use caution
 

There were reports of compatable refrigirants with R-12 using LPG as a propellant and a refrigirant.
Be careful.
With this alternate costing more than R-12 and a conversion kit so inexpensive, where is the value?
Happy Trails Beep Beep from Houston!!!
El Cheapo, Don

Don,

R134a is known to be 80% as efficient as R12, so in hotter climates it is a factor. I have a 1980 300D that I converted to R134a. I replaced the compressor, TXV, receiver/dryer, and refigerant. The 123 a/c systems were not robust to start so the 20% loss in efficiency makes a big difference. Also, Freeze12 costs more than R134a, not R12. It is still more economical than R12 and easier to install than R134a.

While I know most pros don't want to touch anything other than R12 and R134a for fear of contaminating their recovery systems, I still think the compatibility of Freeze12 to R12 makes it a viable alternative.

Freeze 12...
 

Don, Mike is right... many systems don't have the efficiency to tolerate a switch to R-134. For this reason the EPA has allowed some of the properly designed propane/butane mixes to be allowed, providing the system valves have been changed and are properly labled, and that R-134 has been demonstrated to be inadequate for the task. Most of the mixes like Freeze-12 are actually more efficient than R12, and way more efficient than R-134. They mix properly with the lubricants in R-12 systems, and will not cause compressor failures if installed properly. One thing to remember when using these types of gasses is that it doesn't take as much refrigerant to charge the system - ie where you might have used 4 16 oz cans of R-12 to charge a system, you would only need 3 16 oz cans of Freeze-12, due to the difference in the liquid volume. It is my understanding that these propellants are standard equipment in European Mercedes-Benzes and have been used extensively in Australia as well. If you are worried about safety, just keep in mind that your average can of hair spray has almost as much propane in it as your car has refrigerant.

Richard Wooldridge
'82 300D/4.3LV6
'74 280C (with R-12 alternate for 5 yrs now...)
'77 Jag XJ6L (same)
'77 280Z (same)