You are viewing the Serious Explorations Archive.
Click Here to view our message board.


View Full Version : Quick A/C Charge question


dreamr
05-18-2006, 07:50 PM
So just a quick question. Vehicle info is under that picture to the left.,....

My A/c quit blowing cold air toward the end of last fall. I didn't really care as winter was approaching. Now that it is summer I picked up a charge kit from the local Schucks Auto Supply. When I hooked the kit up to my warmed up truck with the A/C on high it read that I had around 18 psi in the system. I ran about 3/4 of the can (19 oz) in and was getting a reading of right at 45 psi. I disconnected the can and let it run for a sec. The air inside was nice and cold :D

Just to make sure all was good I hooked the gauge back up to the low side port. I was now getting a reading of 25psi. I left it hooked while the compressor kicked on and off a few times. The reading did not change. I figured well it "settled" a bit and pulled the trigger to add more r-134a. The gauge instantly jumped up to 45 and stayed there.

So my question is this. Since it is cold air and all, do I just say good enough, or do I need to mess with it more? Sorry this is the first time I have ever recharged A/C. All my cars except the VW have run r-12 so were serviced professionally. The VW never needed it.

Glacier991
05-20-2006, 02:40 AM
The low side should pull down to about 25 psi or so and then the compressor will cycle. The FORD system SHOULD cycle except in very hot weather. Your compressor should not run all the time. Cycling times will depend on a number of factors. In Florida on a HOT day it may cycle little. In Colorado at 85 degrees it may cycle a lot.

Those little pressure gauges are misleading. A gauge set is much better. pressures in AC are not like tire pressures. In a FORD orifice valve system they will fluctuate based on a number of factors. It is NOT like readng your tire air pressure and saying you are low. And pressures MUST be read with the system operating.

If your compressor is constantly running you probably have too much refrigerant in the system. (Not a good thing)

When giving system operation info, some things that are ALWAYS helpful are ambient outside air temp, and vent temp at the time of the test.... if you have a gauge set hi side and low side pressures are also helpful.

dreamr
05-20-2006, 03:22 AM
It was a nice warm day that day, but I have no clue what the ambient temp was. The compressor is kicking on and off as always and things are working normally. I suppose I should have the neighborhood garage test it for me the right way....
I would buy proper gauges rather than the cheapy kit...but my X is the only vehicle I have running a/c now. The Kia is to cheap for air, and I ripped it out of the Mustang rather than converting to 134a...

Thanks for the info Glacier..

Glacier991
05-20-2006, 08:53 PM
If you are compressor cycling on occasion and the vent temps are good... I'd rest that all is ok.

You may have other more pressing needs and I understand, but I am starting to see the gauge sets on sale at harbor freight for about $40.

dreamr
05-21-2006, 02:33 PM
..........................
I am starting to see the gauge sets on sale at harbor freight for about $40.


Hmm I might just have to drive up there I need to get a new timing light and where else is stuff cheaper :D

Thanks Glacier