Hi all
I just installed A/C in a 98 2.5L that never had air (base model). I have all the components installed but not charged yet. There is no wiring whatsoever. In or out. I have a toggle switch that runs to a relay and from there it goes to the low pressure to the high pressure switch then to the compressor. I bypassed the 2 switches and the compressor does kick in. My concern is should I have run the ground wire thru the switches or is it OK to run the hot thru the switches? Or no difference?
Thanks for any help.

 

Well I got it charged Friday and no leaks and wiring was all good. Could only get the dash vent temperature down to 68 degrees. He thought maybe I was leaking air past the blend door. So back to the U pull and get a heater by-pass valve. I installed it but still was getting 68 degrees at the vent. It would cool the cab pretty good but I wanted it lower. After long thought I decided since I had the non A/C control panel I was pulling air (90 degrees and humidity to match) from the outside. So back to the u pull to get a A/C control panel. After I installed it I was able to turn it to "Max" air and that stopped outside air from going through the evaporator. Now my vent temperature is 58 degrees. I am plenty satisfied with how cold it gets in my single cab. Since the "Max" setting only controls the door that brings air from outside or recirculate I can recirculate heated air in winter.
On to the next issue. Since I had wired from a switch on the dash to a relay then to the low pressure then to the high pressure switch then the compressor I was by-passing the computer. The computer would compensate for the extra load when the compressor would kick on. My idle was close to stall after dropping 200 rpms. I was able to compensate by bumping up my rpms with the set screw at the end of the throttle cable. All and all I am happy with it. I have all new components and with vac and 134 charge I came in just under $500.
Had it not been for the people on Ranger forums I would not have known how to do it. I studied and read about every post I could get my hands on for about a month before I was confident enough to try it. Since I'm retired this is a hobby truck that I enjoy working on. These forums have saved me a large amount of money.
Thanks to everyone.