trinary fitting 10mx1.5 for fans

[homemade87]

I did my swap a couple years ago and decided to do a engine change to a ls2. In the process I had learned that a trinary switch will control the fans. I am wanting to put it in line on the high pressure side but I cant seem the find a fitting of any kind. Doc blocks is no longer around and my searched have not come up with anything. The factory 04 switch I got with the truck is a 10mx1.5 thread and I need to add a service port in line some how. What are some of you doing for this install. Do you know of a company that has what I need. Thanks

[jorgensensc]

Check vintage air. That is where I get my trinary switches from.

[homemade87]

I have looked at vintage air with no success. I have the facrory trinary switch from the 04 truck to use with the 04 pcm. I am trying to add it to my high pressure line from the compressor. Apparently there is no one who has a conversion to the new metric size on the new trinary switches that I have seen yet.

I have sence learned it is not a m10 x 1.5 , it is a m10 x 1.25 on the trinary switch.

I am going to try my hand on alum brazing a fitting in the line. I found some brazing rods for alum and got a fitting from a old line and see what happens.

I was hoping to find a male female fitting that had a service port on it to put in line.

Wish me luck, I will let you know how it worked out.

[jorgensensc]

Ok, help me understand please. What year vehicle and AC system? Why are you going through the PCM? The trinary gives power to the compressor as long as the head pressure isn't too high. A proper trinary switch also gives ground for fan relay when the head pressure reaches a certain threshold. That is why the fans won't run when driving on the freeway( in a properly working system of course). Contrary to popular belief it is not a great idea to have the fan automatically come on when the a comes on. Such as while driving down the freeway and the system doesn't need the head pressure reduced.

Shawn

[homemade87]

Heres what I have experienced with out the trinary. This is on a 82 c10. I am using the 82 controls to turn the a/c clutch on. My 04 pcm is a serial data signal and no way to use it with out the bcm. I am also using the 82 low pressure switch for the compressor cut out. This seems to work fine.

For the fans, I am running a dual fan set up with the factory three relay. This allows the low speed to run the two fans in parallel with good air flow and runs a lot quieter. What the high pressure trinay switch will do in monitor the high pressure from the compressor. When it sees what it needs it will turn the low speed on ( each fan on at 50% at the same time ). If the head pressure gets to high it will turn the high speed on ( both fans on at 100%) until pressure is dropped. If the trinary is not used my only option is to turn the fans on at high speed at all times. I have found out that at start up if a/c is on, the compressor and fans (high speed) are coming on at the same time and the engine will drag hard ( almost stall) for a few seconds trying to catch up getting the alternator and comp going. With the trinary the fan will not come on untill it sees pressure there for a delay at start up for the fans.
The fans dont always need to run on high, this way the computor knows what to do.

Also another benefit from this is fuel economy. Gm has designed it so the fans will shut off at about 35 to 40mph for engine and a/c. If by chance the pressure in the system gets to high it will cut it back on to control it. With both fans on high at all times iit really drags the alternator down there for lower fuel econony.

This is the way gm had intended for this system to work. This is nothing I had dreamed up.The only real difference in what I am doing is I can not use the pcm for a/c request because of the serial data signal and shut the compressor off if the pressure gets to high. I have been running it this way with out the trinary for some time with out any problem. I suspect that most are without a high pressure cut out. Once I get things together I may look into adding a relay to the trinay and run the comp clutch thru it to shut it of in case too high pressure.

I have got everything I need to try to braze a fitting in today. I hope this works. If it dont, I am not sure what I am going to have to do to get it in there. I will figure something out . I was hoping someone had already figured it out and had a source for parts.


( not a great idea to have the fan automatically come on when the a comes on )

I assume the statement above was to say when the a/c ( meaning comp clutch )comes on in your post. And you are correct. With the trinay there would be almost no reason for the fan and clutch to come on at the same time. If the comp is not running there would be no signal from the trinary switch to turn the fan on. Even if the engine was shut off and restarted right quick I think the pcm has a delay and will not start the fans right away.

[dayj1]

Originally Posted by homemade87

I did my swap a couple years ago and decided to do a engine change to a ls2. In the process I had learned that a trinary switch will control the fans. I am wanting to put it in line on the high pressure side but I cant seem the find a fitting of any kind. Doc blocks is no longer around and my searched have not come up with anything. The factory 04 switch I got with the truck is a 10mx1.5 thread and I need to add a service port in line some how. What are some of you doing for this install. Do you know of a company that has what I need. Thanks

The fitting on the '04 high pressure switch is M10 female threads, correct?

If so, there are adapters that will screw on an R12 service port (7/16 female flare) and adapt it to a male M10 switch port. Here is one example:

http://www.apairinc.com/dealer/detail.asp?part=461-3130

If your accumulator/drier has an unused port, the adapter may be all you need. Fittings are also available that will add an "R12 sized" service port inline that you can screw the adapter on and finally the switch.

I hope those parts are what you're looking for, but I'm not sure that everything will work the way you expect once it is wired up. The factory switch is just a high pressure switch (not a trinary switch) and doesn't behave exactly the way that you describe.

Good luck with your project!

[homemade87]

Originally Posted by dayj1

The fitting on the '04 high pressure switch is M10 female threads, correct?

If so, there are adapters that will screw on an R12 service port (7/16 female flare) and adapt it to a male M10 switch port. Here is one example:

http://www.apairinc.com/dealer/detail.asp?part=461-3130

If your accumulator/drier has an unused port, the adapter may be all you need. Fittings are also available that will add an "R12 sized" service port inline that you can screw the adapter on and finally the switch.

I hope those parts are what you're looking for, but I'm not sure that everything will work the way you expect once it is wired up. The factory switch is just a high pressure switch (not a trinary switch) and doesn't behave exactly the way that you describe.


Good luck with your project!

The accumulator is the low pressure side and not the high pressure side. I am not using the 82 factory switch on the high side which is just a single switch .You must have not understood what I was trying to do. I am using the 04 trinay switch which is used with the pcm to control the fans just like gm does. The adapter you suggest may just work to add the 04 switch to the system. But it does not show the thread size. What is needed is a m10 x 1.25. It is a male thread . The switch is a female. And yes it will work if I get the o4 switch added. This is how GM does it.

[ls1nova71]

Just curious, but are you sureits going to work with the '04 switch without the PCM seeing an A/C request signal? Also what OS are you running? '04 with the fans enabled via the recirculate door wire?

[homemade87]

Originally Posted by ls1nova71

Just curious, but are you sureits going to work with the '04 switch without the PCM seeing an A/C request signal? Also what OS are you running? '04 with the fans enabled via the recirculate door wire?

Yes it will work. The trinary works independently and does not need a/c request. The 82 factory system turn on the compressor .I believe the o4 and up pcm does this. There is a thread in here that discuses this an some getting it to work. Not sure what OS means and what you are asking on the recirculate door wire.

[ls1nova71]

Originally Posted by homemade87

Yes it will work. The trinary works independently and does not need a/c request. The 82 factory system turn on the compressor .I believe the o4 and up pcm does this. There is a thread in here that discuses this an some getting it to work. Not sure what OS means and what you are asking on the recirculate door wire.

OS is 'operating system' such as '04 Silverado, F body or such. The reason I asked is because 2004 Silverado's didn't have electric fans. They can be enabled in the tune though, but you have to put a wire in for one fan, and the other wire is there, but it's originally used for the recirculation door on the Silverado's A/C system. The 2004 uses a 3 wire high pressure sensor, and a regular 2 wire low pressure sensor. Certain DTC's will keep the A/C from coming on when it's controlled by the PCM. Also, it could turn the fans on all the time, as a failsafe. If it works that would be great, but if it doesn't, I've heard that the A/C request cha be changed in the tune from serial, to 12v, but you need the proper software. I believe Tunercat will do it, but HPTuners won't.

[dayj1]

Originally Posted by homemade87

The accumulator is the low pressure side and not the high pressure side. I am not using the 82 factory switch on the high side which is just a single switch .You must have not understood what I was trying to do. I am using the 04 trinay switch which is used with the pcm to control the fans just like gm does. The adapter you suggest may just work to add the 04 switch to the system. But it does not show the thread size. What is needed is a m10 x 1.25. It is a male thread . The switch is a female. And yes it will work if I get the o4 switch added. This is how GM does it.

I completely understand how the factory system works. I've just never seen anything reliable or conclusive that it will work in a swap situation without the "complete" setup with the HVAC controller from the donor vehicle. I'd really like to hear back from you one way or another on how it works out.

As far as finding a fitting, how is your system configured on the high side? Is it hard line or hose? Is it #8 or #6? Are the connections flare or o-ring? Do you already have a high-side service port? Is the port R12 or R134a?

[homemade87]

Originally Posted by dayj1

I completely understand how the factory system works. I've just never seen anything reliable or conclusive that it will work in a swap situation without the "complete" setup with the HVAC controller from the donor vehicle. I'd really like to hear back from you one way or another on how it works out.

As far as finding a fitting, how is your system configured on the high side? Is it hard line or hose? Is it #8 or #6? Are the connections flare or o-ring? Do you already have a high-side service port? Is the port R12 or R134a?

I will be glad to report back on how things work out. I had some sucsess on brazing a fitting on the high side pressure today. I removed the hose from what I had and drilled the tube and I had found a fitting from a old line and removed it and installed it. Looks like it will work good. Also got the wires run to the pcm . Now I have to get to the parts store and get the hose reinstalled on the fitting.

I have got a few more things to get together on the truck before I can get it running. Wont be long though. (exhaust and long tube headers)

Also you are correct if you are trying to use the pcm for a/c request on o4 and up. You do have to have the controler to do this. But the trinary works on its own and does not have to have a/c request to work. That is why what I am doing will work. Some earlier pcms can control the a/c request with 12v thru the pcm. The o4 and up do it with a serial data.

I will keep you posted