Suburban A/C fix + Vintage Air?

[swissarmychainsaw]

I found this wire tucked away for safe keeping.

Is this the connector for the Compressor? If so, that good news!
Can anyone confirm? Ya'll bein' real quiet!

[hatzie]

That looks like the connector used on some of the Harrison Frigidaire A6 and R4 compressors.
The wire colors are correct for that.
IIRC it's Packard 56 terminals inside a special connector shell.

When I convert over to the Sanden style compressor I run the ground through the High Pressure Cutout Switch and leave the LPCO in the hot as originally wired. You can run the HPCO in series with the LPCO but it's easier to put it in the ground side.

[swissarmychainsaw]

Originally Posted by hatzie

...Snip...

When I convert over to the Sanden style compressor I run the ground through the High Pressure Cutout Switch and leave the LPCO in the hot as originally wired. You can run the HPCO in series with the LPCO but it's easier to put it in the ground side.

Thanks for this.
I just reached out to the supplier of my parts:

The modern compressor do not have any switches in them, so it is recommended to install one. Here is a link to a very easy to install switch kit.

https://www.originalair.com/ac-high-...tch-kit-o-ring

In your situation, it would need to be attached to the lower fitting of the condenser (#6) and then attach the hose directly to that.

Just ordered this, but I don't think it will get here in time for my vacation plans!

[hatzie]

Originally Posted by swissarmychainsaw

Thanks for this.
I just reached out to the supplier of my parts:

The modern compressor do not have any switches in them, so it is recommended to install one. Here is a link to a very easy to install switch kit.

https://www.originalair.com/ac-high-...tch-kit-o-ring

In your situation, it would need to be attached to the lower fitting of the condenser (#6) and then attach the hose directly to that.

Just ordered this, but I don't think it will get here in time for my vacation plans!

You could get a crimp in pressure switch fitting and install in the hose right off the compressor head.

The compressor head fittings, be it a Sanden or one of the Harrison units, can be acquired with an HPCO threaded switch fitting... and even both LPCO & HPCO threaded switch fittings.

[swissarmychainsaw]

Originally Posted by hatzie

You could get a crimp in pressure switch fitting and install in the hose right off the compressor head.

The compressor head fittings, be it a Sanden or one of the Harrison units, can be acquired with an HPCO threaded switch fitting... and even both LPCO & HPCO threaded switch fittings.

Like this?
https://www.summitracing.com/parts/vta-24678-vus

So is the Low pressure switch a "binary" and the high pressure "trinary"?

Edit: Found this on "trinary switch" -- If you need to trigger an electric fan, use one!
https://www.youtube.com/watch?v=l604JCZx_ow

[swissarmychainsaw]

Ok, now I'm scratching my head.

So I believe this to be a low pressure switch, can anyone confirm that?

Can I also use that unused "port" (with the black cap) for a high pressure trinary switch?

[hatzie]

That is indeed the LPCO switch.
The black capped fitting is the low pressure manifold gauge service connection.

The HPCO has to be in the high pressure side of the system. Usually right off the compressor in the high side line.

[swissarmychainsaw]

Holy Cow, I ordered a Trinary switch from Summit Racing YESTERDAY and it's in the mailbox already. Less than 24 hours. Crazy.



Here we go!

Brackets for the condenser. I took the "install kit" cut it and bent it to use existing hols in the core support.




Final of the Condenser bracket install. Getting this all in there was the hardest part so far.

[swissarmychainsaw]

The moment of truth:



The first crimp!



Now like 45 to go!



Mocking up:



Routing the hoses is harder than I thought it would be.

I don't want it to look like a cluster. Every combination looks weird!

[swissarmychainsaw]

Running the lines and mocking things up before "the final crimpdown!"

[swissarmychainsaw]

This gives me feelings of optimism:



Drain Hole from "kustom drain holes express"



yes, buy some extra length hose, just in case!



Aaaaand Here is the final mock up before all the crimpin' goes down.
Might not win a trophy, but if she blows cold, well, winning!

It looks like those hoses touch the belt in this pic, but there is plenty of room.

[swissarmychainsaw]

Carry on my wayward son...












Ok so all crimped up and read to rock and roll.

Now for the bad news:
Never was able to pull more vacuum than this.



And after I shut it off, I lose vacuum.






So I have a leak in all my glorious crimps and connections.

What next?

[swissarmychainsaw]

Seems the smart thing to do is to put some compressed air into the system and spray some soapy water the connections.

Here is a video that shows the procedure I used
https://www.youtube.com/watch?v=J6DSpx1V3Ms

Basically you put a rubber tipped air gun where the yellow vacuum pump hose goes, and pressurize the system, then with a spray bottle of soap and water get to squirting on your joints.
The great thing about air leaks is that you can *hear them!

So I found the leak!



This puppy was hissing air.

Now, no one in their right mind would put a junk yard Low Pressure Cut Off switch on their brand spanking new AC system...would they???

Next up, we put it back on the vacuum pump and see if it holds! Fingers crossed.

[jjzepplin]

Hang in there! It's probably something simple. Check all your fittings for O rings and damaged O rings as well as switches.

[hatzie]

Make sure the Schraeder valve on the service port that's on the side of the accumulator isn't leaking.

[swissarmychainsaw]

Originally Posted by hatzie

Let us know how the Mastercool Hydracrimp knockoff works.

This thing worked great, I think I only had to make a dozen crimps, but it worked very well. (So far not leaking).

Edit: I was looking at the mechanical (non-hydraulic) mastercool one, but decided on this one. I'm glad I did because at some point you will need to make a crimp in a hard to reach place and the hydraulic one is the no-brainer choice as it does not need to be held in a vise.

[swissarmychainsaw]

Originally Posted by hatzie

Looks like you have a compressor cycling thermal cutoff switch with a capillary tube in the Evaporator. There should be a Low pressure cutoff switch on the accumulator as well. The aftermarket compressor and or hoses likely has provision for a high pressure cutout switch. If you're running R134a you'll want to add a HPCO switch in series with the LPCO and thermal switches because it has a tendency to run much higher pressures than R12 or HC blends.
I'd use a relay to offload the control amperage to the actual compressor clutch so the high amp load of engaging the electromagnet is run through an easy to replace $1.25 relay rather than the HVAC controls and the LPCO and Thermal switches.

Get a relay socket rather than using 1/4" disconnects. It makes the wiring job look better and it's much easier to replace the relay when and if it needs to be done.
Run a ground in series through the LPCO, HPCO, and Thermal switch to terminal 85 of a Mini ISO Bosch Automotive relay.
Run the Green AC compressor "on" wire from the HVAC control panel to terminal 86 of the same relay.
Run a 14ga wire through a 16ga fusible link or a 20A ATC fuse from the J stud on the firewall to the relay common terminal 30.
Run a 14ga wire from relay terminal 87 (normally open) to the actual compressor clutch plug.

I'm trying to get the wiring sorted out for the trinary switch and Vintage Air only used two colors of wires.
Does this look right?



Upper left Black wire: This is the Original ON green wire that passes through the Low Pressure switch. This wire originally would have plugged directly to the compressor.

Upper right blue wire: To terminal 86 (trigger) of the Fan relay.

Lower left blue: Keyed power.

Lower right black: to 86 (trigger) of Compressor relay.

Thanks for the help on this!
I have a new LPCO on order, I'm getting close!

[swissarmychainsaw]

My fan relay has a part number on it. I went and bought another one just to have the instructions.

"Green Wire (Air conditioning override) ... attach the green wire to the A/C Clutch wire"





If I understand this correctly this means when the green wire gets power, the fan gets triggered. (you can't actually see where the wires are connected as they are epoxied together.

If this is true then I don't have to hook up the blue wires of the Trianary switch.

Key On:
I just connected the Green wire to the battery assuming that putting voltage to that wire would trigger the fan to come on.
Nothing happened.

I'm kinda lost on this wiring setup.

Here is why my jumble jangle switch looks like.
I need to spend some time and clean up all the janky wiring the PO left behind.

[swissarmychainsaw]

I had a couple issues getting the right LPCO switch, and once I got it, I had trouble getting it to seal. Pro Tip: hand tight only!

Also the rear blower was hitting the case so I had to pull that down and align the motor better.

First I was going to trim it:





The fix was to undo the one bolt on the fan clamp and slide it over a bit so the blades fit in the case properly without rubbing.

Test before you hang it!



Otherwise system is now holding pressure, today I'm getting the wiring sorted out, and hopefully put some charge to it!

[jjzepplin]

Yeehaw!

[SCOTI]

Persistence!

[swissarmychainsaw]

Thanks for the encouragement fellas!

This seems really simple when I draw up this pic, but it took me a while to get there.
Thanks to @hatzie for suggesting this wiring strategy of using a relay for the compressor!

Not shown is the relay and switch for the rear AC Blower.



This means the wiring is now hooked up, and I can potentially run the system today.
Is today THE DAY?

I'm sure there are about 30 things that need buttoning up, but I'm going for it!

Here is some wiring for your enjoyment, not many folks appreciate a good crimp!



A little wire loom makes those wires look a lot better:



This is when you know you should step away from the heat gun.

[jjzepplin]

FANcy!

[swissarmychainsaw]

I need to add about 3 oz of PAG oil to this system.

I arrived at that number by looking at the manual and talking to the sales/tech, the original system (with dual AC!) had 3 oz more then the since evap system.

So assuming the compressor has enough oil in it for a single AC system, we then will add 3 oz for a dual.

How should I add the oil?

I need to pull a vacuum on it anyway, so it's open, now.

I'm seriously considering opening one of the rear lines and just pouring 3 oz in.
Considering the rear lines are 15 feet long, I don't think it should be a problem.

[swissarmychainsaw]

Wiring done enough to run the system



Only add to the high pressure (discharge) side or your compressor will suck in liquid oil and the sun will stop spinning in the sky!



Make sure you have a good assistant!



Right now, we are pulling a vacuum and double checking Last Time for leaks!