I am trying to fix the A/C on my van. I have a 2003 dodge 1500 cargo van. With a small v-8. I replaced the compressor (the old compressor was locked up). No power seams to be getting to the A/C clutch. There is a fuse box by the battery. Is there any other fuse boxes. What should I do?

 

Has the system been properly evacuated and recharged with the correct amount of oil and R138a?

 

Where can I buy some of that R138a?

 

Bite me Mr. Picky!

They keep it right in between the R-137a and the R-139a, if you must know.

 

If its just after replacing the compressor then there's no refrigerant and the low pressure cut-off wont let it turn on.

On mine (1999 2500 w/ 5.2L) the connector is on passenger side right in front of the evaporator housing and the dryer on the low pressure line.

Take that off and jumper it with a bent paper cliip and it should make the compressor come on while you put the refrigerant in.

 

No, no, no, no, no, no, and no! Did I happen to mention the word, "NO"? If you do this, then you can kiss your new compressor good-bye.

First and foremost the compressor needs to be filled with the correct type and amount of PAG oil. Then the system needs to be evacuated. Then add two or so cans of R-137a and the low pressure switch will close and the compressor will run. Once the compressor is running, the balance of the R-137a can be added.

 

Hey, those who dish it out have to take it once in a while, too.

 

To evacuate means to remove any moisture that might have entered the a/c system when taken apart. Usually the machine that does the evacuating is the same machine that fills your system with r134a. Cost around $120 depending on how much freon your system takes. Most a/c repair shops has this machine and takes about 30 minutes to do the job.

 

Well, removing moisture is side effect of evacuating the system. Evacuation means attaching a pump to the A/C system and then pulling a vacuum (negative pressure) to the sealed refrigerant system.

SOP is to run the vacuum pump for about 10 minutes and then monitor the vacuum gauge. If it indicates a rise of 5mm of mercury (or more) within one minute then your system has a leak which needs to be located and repaired before you can charge the system with refrigerant.

After repairs you have to evacuate again, ensure there are no additional leaks, then run the pump for about 20 minutes to below 4mm of mercury before charging the system.