GmikeHall

I am in the process of getting my AC system sorted out on my 2002 2500 suburban which I did a Cummins swap in. I Have been driving it a while to verify everything is in good working order so its now time to get the AC and cruise control working. I almost have the custom AC lines worked out and just waiting on the fittings and brazing rods to make up the lines. I jumped on the wiring thinking it would be simple but I have run into a few issues I am wondering how to sort out. I had noticed the AC system had a low pressure switch and two high pressure switches. One high pressure switch is on the compressor and the other is between the compressor and condenser. The issue is I am using all Cummins accessories so the compressor has no provisions for a pressure sensor like the GM unit. what exactly is that sensor for? Most AC systems only have two pressure sensors to deal with and really unsure how I can solve this issue with this setup. Should I add another fitting and just install a second high pressure sensors even though its not exactly the same as what is on the GM compressor? Could I just eliminate it and use a jumper to satisfy the HVAC controls?

Here is the custom compressor manifold I am making to use the factory suburban AC lines without mods

GmikeHall

I came across an explanation on the 3 different pressure switches. Low pressure is for the system cycle, front high pressure is for turning on Aux fans or whatever and High pressure cut out and for over pressure situations if something has failed. I think I may explore making a custom fitting to add this cut out switch in line just behind the compressor.

Ls1Rx-7

iTrader: (4)

What about just keeping the gm compressor and ac system completely intact and just run a custom bracket to mount the compressor?

GmikeHall

Well I didnt foresee this issue popping up so I had already bought a new Denso compressor for the project. If I would have realized the GM ac used 3 different switches I would have possibly made a custom AC bracket. the other issue with running a GM compressor is they all have fewer ribs on the pulley than the Cummins so that its would pose another problem to have to resolve. My plans are to just run the Cummins compressor with the factory pressure release valve. this 3rd switch on the compressor is strictly for safety and the Cummins compressor will be safe with the relief valve in place. I may make a custom fitting to weld onto my AC manifold I made to add the the switch but I dont think its really necessary now. Sure am looking forward to getting the AC functioning and then the cruise control next. This suburban is my favorite thing to drive currently.