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Re: Installing A/C on my 75 Vette (2/12)
 2/9/20 2:38pm
NorskyLifetime Member
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Twin Lakes, CO - USA

Vette(s):
SOLD - "The Toy" - 1970 Convertible
SOLD - "The Beast" - 1990 ZR-1 (#682)
"BLKBRRD" - 1978 Trans Am, 400ci/225hp, 4 spd, Black w/black interior, Hurst t-tops


Joined: 1/23/2002
Posts: 6929

Great write-up Bill.  Nice to know that there are outfits out there who do a better than average job on their instructions AND have knowledgeable folks on the Help Line to get one through problems.



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Where I've been in a Corvette...!!!

Re: Installing A/C on my 75 Vette (3/12)
 2/10/20 2:33am
73shark
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Overland Park, KS - USA

Vette(s):
1973 Orange Metallic Coupe (orig owner), L82, 4 spd (WR), PS, (A/C & PW (I installed from wrecked 73)), leather, AM/FM Stereo, ran with '65 FI unit earlier & will again some day.


Joined: 7/9/2003
Posts: 664

That sounds like a lot of work. Seems like a lot more than when I put factory air in mine about a year after I got it. I realized after about a year that not ordering it with factory air was a big mistake. I salvaged all of the parts out of a wrecked 73. However, I didn't have to remove the driver side instrument cluster for the factory air. Probably because the ductwork was on the bottom of everything.

Surprised since yours had factory air originally that there weren't holes for the condenser.

Great writeup.



|UPDATED|2/9/2020 11:33:01 PM (AZT)|/UPDATED|


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1973 L-82 4 spd

Re: Installing A/C on my 75 Vette (4/12)
 2/10/20 10:58am
BillHanna
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Cana, VA - USA

Vette(s):
1975 Stingray 71 350 engine Flat top pistons Sniper fuel injection Hyperspark ignition Vintage Air air conditioning Borgeson power steering box


Joined: 7/3/2016
Posts: 238

73shark said:

That sounds like a lot of work. Seems like a lot more than when I put factory air in mine about a year after I got it. I realized after about a year that not ordering it with factory air was a big mistake. I salvaged all of the parts out of a wrecked 73. However, I didn't have to remove the driver side instrument cluster for the factory air. Probably because the ductwork was on the bottom of everything.

Surprised since yours had factory air originally that there weren't holes for the condenser.

Great writeup.



A big part of this install was removing the factory air system.  Overall, I put about 50 hours into this project -- which seems quite a bit to me.  I read one post that someone paid over two-thousand dollars to have his installed, so maybe my time was not that far off.  Doing a similar job a second time would surely take a lot less time, knowing what steps to take ahead of time.

The only thing I can think of why there were no holes in the bottom for the condenser is that someone must have replaced the core support at some time.


 



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Re: Installing A/C on my 75 Vette (5/12)
 4/6/21 9:16am
Stingre'
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Torrance, CA - USA

Vette(s):
1974 Stingray Blue/Black needs work


Joined: 4/7/2017
Posts: 5

Did you install Binary or Trinary ? I'm having trouble finding connections for the blue wires, one goes to ground and other to ?

Re: Installing A/C on my 75 Vette (6/12)
 4/6/21 11:59am
BillHanna
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Cana, VA - USA

Vette(s):
1975 Stingray 71 350 engine Flat top pistons Sniper fuel injection Hyperspark ignition Vintage Air air conditioning Borgeson power steering box


Joined: 7/3/2016
Posts: 238

Stingre' said:

Did you install Binary or Trinary ? I'm having trouble finding connections for the blue wires, one goes to ground and other to ?


I originally had the  binary switch, but then added the electric fan, so I switched to the trinary switch.

Did you get the Vintage Air electric fan?  If so, this should have come with a plug that fits the plug from the trinary switch.  They would have included a diagram on how this is wired.  If you don't have this, let me know and I can send a picture of the diagram.

I tried to see how I wired it, but without removing the hood, I can't see the wires.

Depending on which situation you are in, I can probably provide more help, but I need to know if you have their electric fan.

 

 



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Re: Installing A/C on my 75 Vette (7/12)
 4/6/21 12:53pm
Stingre'
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Torrance, CA - USA

Vette(s):
1974 Stingray Blue/Black needs work


Joined: 4/7/2017
Posts: 5

Yes, I have DeWitts dual electric fans, I'm confused how to wire the trinary, one blue goes to ground and the other to temp sensor ? I tried this and the fan won't start when I start AC. I need to check the wiring...

Re: Installing A/C on my 75 Vette (8/12)
 4/6/21 12:57pm
Stingre'
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Torrance, CA - USA

Vette(s):
1974 Stingray Blue/Black needs work


Joined: 4/7/2017
Posts: 5

Pretty much same setup you have, 350sbc, Sniper Efi and Vintage air AC

Re: Installing A/C on my 75 Vette (9/12)
 4/6/21 3:05pm
BillHanna
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Cana, VA - USA

Vette(s):
1975 Stingray 71 350 engine Flat top pistons Sniper fuel injection Hyperspark ignition Vintage Air air conditioning Borgeson power steering box


Joined: 7/3/2016
Posts: 238

Here is the wiring diagram for the AC with cooling fan:

Does this help?

 

 

 



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Re: Installing A/C on my 75 Vette (10/12)
 4/6/21 4:39pm
Stingre'
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Torrance, CA - USA

Vette(s):
1974 Stingray Blue/Black needs work


Joined: 4/7/2017
Posts: 5

yeah I guess physically do you have a blue wire going to the thermostat ?

Re: Installing A/C on my 75 Vette (11/12)
 4/6/21 4:48pm
BillHanna
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Cana, VA - USA

Vette(s):
1975 Stingray 71 350 engine Flat top pistons Sniper fuel injection Hyperspark ignition Vintage Air air conditioning Borgeson power steering box


Joined: 7/3/2016
Posts: 238

Stingre' said:

yeah I guess physically do you have a blue wire going to the thermostat ?


The blue wire comes from the AC control, goes through the trinary switch, then to the compressor.

My understanding of one function of this switch is to turn on the fans only when the pressure exceeds a certain value.  This is controlled by the blue wire going to the fan relay (see the diagram).  The fan does not come on immediately when the AC is turned on.

(The trinary switch also turns off the compressor if the pressure is too high or low.)



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Re: Installing A/C on my 75 Vette (12/12)
 4/7/21 8:29am
Stingre'
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Torrance, CA - USA

Vette(s):
1974 Stingray Blue/Black needs work


Joined: 4/7/2017
Posts: 5

ok, that helps. Friday I'm checking the wiring again, something isn't working right. Appreciate your help.

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