Need help recharging the AC on a 97 Jeep Cherokee Sport

Yeah, I'd be interested in knowing that too. Drifter "I've been here, I've been there..."

Not a good method to use! Each manufacturer has a specific amount of refrigerant they require to be installed by weight. You do this with the system off and measure by the total refrigerant installed. Once you have the correct amount installed you need to check the super heat combined with discharge air temp, ambient air temp and the high and low side based on the temperature chart anything else is just a SWAG and not contusive to a good installation. Also in a new or rebuilt system you need to draw a 500 micron vacuum to get all the bad stuff out and re introduce the correct amount of compressor oil.

Robb S via CarKB.com did pass the time by typing:

And you never will. That's why the charging instructions always say to have the AC on max and the low side switch bypassed if required to turn on the compressor.

That's why you bypass the low side switch with a jumper wire when starting from a low or zero charge.

Agreed. The only time you should add oil is when you replace the accumulator. There is no easy way of testing oil level.

Thanks for the advice fellas. I got a recharge kit and did it this afternoon. Drove around for a hour and tested it again. Added maybe

Those 100 degree days shouldn't have me down now.

Thanks again,

Jeff

bypass that lowside switch on a unit (besides an automotive one) while it's in a vacuum and bring the compressor on......you'll be buying a new compressor.....

DougW wrote:

"Once a year I had to give it another can."

In case you haven't figured this out yet, you have a leak that should be fixed. After I got tired of giving it a can every year, I bit the bullet, and bought a compressor, hoses, and an O-ring kit. I haven't added a can in over two years now.

Earle

Is it true you have to run your AC at least once a month to lubricate the seals? I heard this from someone a long time ago, but I've never heard it again.

Doug did pass the time by typing:

Yep. Seals, pump, prevent sedimentation.

Keep in mind that defrost also runs the AC.

I have a '98 TJ Sport with factory AC.

I picked up an R134a recharging kit the other night because my AC was blowing warm air on our beautiful 90 degree days!

I followed the directions to the letter but the system still didn't get cool. The compressor was kicking in as it should be(based on a butt-load of past postings I read about the subject here).

The tubing leading into the firewall just got a little cool, it didn't get cold. I'm afraid to add more refrigerant because I don't want to have too much pressure in the system. The refill package I bought doesn't have numeric pressure gauge, it just has the low/good/toomuch colors..

I'm no professional mechanic, so are there some basic troubleshooting things I could try here?

Thanks,

Tim

If you use a heat gun on the charging cylinder you can, I prefer doing it that way to get the exact OEM recharge. Once the system is filled then I run the compressor I have never had a problem and it takes no longer to fill an auto ac system a 400 ton chiller is a different story. Also another trick is leaving the system in a vacuum and draw in the refrigerant. Coasty