Georgia Fiero Club Forum

All Things Fiero => Tech Tips, Tech Questions => Topic started by: f85gtron on September 07, 2015, 12:21:52 am

Title: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 12:21:52 am: I'm adding ac to my non ac (soon to be past tense) car.
First off, the differences between the two hvac boxes cannot be ignored.

The ac box uses motors to change the flaps inside and is controlled by the ac control head.
The non ac box uses only push-pull cables, so the circuit to control these has to be added.
The second biggest difference, other than the obvious ac stuff, is the heater core is different. Because of the heater core position the ac box, I had to either buy ac heater hoses, or add a foot to each hose to reach the new heater core position.

To get the old box out and the new box in,.i had to remove the dash, and the spare tire tub up front. I also had to unbolt the brake booster to get enough movement to clear the boxes.

While the dash was out, i was able to make sense of the wiring. The ac box has four blower speeds and my non ac box only had 3, so i added the extra circuit for that.
I had to tap the fan ground to trip it on when ac is engaged.
I had to run an ac request line to the ecm, so it can do it's thing, like idling up to compensate for compressor draw.
I had to run power to the control head, so it can control the door motors.

Running the lines and pipes was just nuts and bolts stuff. There's holes for the mounts on all components already,.so it's just a matter of putting it together.

I have yet to install the compressor, so success has yet to be determined! But so far, there are volts where there should be volts and signals where signals go, so, so far so good!
Title: Re: Adding ac to non ac car!
Post by: pgackerman on September 07, 2015, 07:52:04 am: And it only took him 15 minutes!

Can't see the pictures Dude.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 08:22:45 am: That's weird. I loved in from a different machine and anonymously and the pics came up. Wi er d
Title: Re: Adding ac to non ac car!
Post by: Fierofool on September 07, 2015, 08:33:19 am: It reads like it's very good directions, but I can't see the pictures, either.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 08:37:38 am: I can't figure out why the pics aren't working on your end?
Try https://goo.gl/photos/U9xJv5P5w4vjeqyTA (https://goo.gl/photos/U9xJv5P5w4vjeqyTA)
Title: Re: Adding ac to non ac car!
Post by: TopNotch on September 07, 2015, 08:47:10 am: That works. Your pictures in the above posts are hosted by "googleusercontent.com", and it's my guess that you have to be a google user (whatever that is) to see them.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 10:32:00 am: Thanks. That's new. I used to be able to share photos from there. I'll look for a work around.
Title: Re: Adding ac to non ac car!
Post by: Fierofool on September 07, 2015, 11:39:05 am: It's strange. After Pat posted, the your first picture with the airboxes stacked up was visible in your original post, but none of the others. I was using Firefox as my browser. I'm now on Melanie's laptop using Firefox and I can't see any of your original post pictures. Your link is still visible, though.
Title: Re: Adding ac to non ac car!
Post by: Raydar on September 07, 2015, 11:48:17 am: I still can't see any of them, except at the goo.gl link.

With that said, you're much more "adventurous" than I am. I have heard about A/C being retrofit, but I would have never attempted to do it. (The Fiero Factory has also turned down this same job.)
As for all the missing circuits, I wonder if it wouldn't be as easy to just replace harnesses in their entirety, instead of adding circuits. But it's really easy to second guess, while I'm sitting here on my azz, so I won't. :D
Best of luck with your endeavor.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 11:56:48 am: It would be easier, and harder at the same time. The interior harness would have to be pulled cross-car. i pulled the ac stuff from an 84 and the wiring is different than the remainder years, so it was easier to run what i needed. I basically repinned the c100 block, the blower switch pigtail to match my year's pinout so the next guy would find it factory. The added circuits are routed and pinned exactly where they're supposed to be. If I didn't post about it, you'd think my car came that way....except for the rpo.
Title: Re: Adding ac to non ac car!
Post by: Raydar on September 07, 2015, 04:41:43 pm: Excellent! Congrats on your patience and attention to detail.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on September 07, 2015, 05:29:50 pm: It's not hard. It's easier than pulling and rebuilding a motor, front end, or anything else like that. Using the cuss-o-meter, it went off more during a fuel tank drop and pump change than it did during this job. Seems to me they are missing out on some easy revenue. Most folks think ac is voodoo anyway.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on April 16, 2017, 12:48:36 am: Update: 2 years later.....FINALLY flushed the lines and replaced all orings and put a charge on it. The relay was bad, so had to replace it. One of the cutoff switches on the compressor has a bad plug, so I had to whack on it a bit.....IT WORKS! It felt REALLY weird driving through the carwash this evening with the ac on! First time ever for this car!
Title: Re: Adding ac to non ac car!
Post by: GTRS Fiero on April 16, 2017, 12:59:08 am: Just in time for summer.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on April 16, 2017, 12:43:03 pm: I have to replace the seats now from sweating them out ! Ewe!
Title: Re: Adding ac to non ac car!
Post by: GTRS Fiero on April 16, 2017, 12:49:29 pm: Seriously? It was warm driving mine to Texas, last Fall, with no AC, but I opened the windows, and let the wind cool me. You know, 2/80 AC. I grew up with no AC. It was a luxury when we got a van that had AC. It doesn't get as hot as it used to, so I guess it isn't as hard on me.

If you start to sweat, you change positions to allow better airflow to that area.

Admittedly, it can be miserable when hot and rainy, but I don't drive my Fiero then, anyway.
Title: Re: Adding ac to non ac car!
Post by: Raydar on April 16, 2017, 02:19:01 pm: When you get to be old and "chunky" like me, you really need A/C.
Title: Re: Adding ac to non ac car!
Post by: f85gtron on April 16, 2017, 04:17:22 pm: Quote from: Raydar on April 16, 2017, 02:19:01 pm
When you get to be old and "chunky" like me, you really need A/C.
Yes. I think that's my issue.
Title: Re: Adding ac to non ac car!
Post by: Raydar on April 22, 2017, 10:52:15 am: Still have your non-A/C control head?

Someone is looking for one.
http://www.fiero.nl/forum/Forum4/HTML/075443.html
Title: Re: Adding ac to non ac car!
Post by: f85gtron on April 22, 2017, 01:44:06 pm: Cheese-wiz Radar! Thanks! I pm him via pff
Title: Re: Adding ac to non ac car!
Post by: GTRS Fiero on August 05, 2019, 06:39:22 pm: Quote from: f85gtron on September 07, 2015, 12:21:52 am
I'm adding ac to my non ac (soon to be past tense) car.
First off, the differences between the two hvac boxes cannot be ignored.

The ac box uses motors to change the flaps inside and is controlled by the ac control head.
The non ac box uses only push-pull cables, so the circuit to control these has to be added.
The second biggest difference, other than the obvious ac stuff, is the heater core is different. Because of the heater core position the ac box, I had to either buy ac heater hoses, or add a foot to each hose to reach the new heater core position.

To get the old box out and the new box in,.i had to remove the dash, and the spare tire tub up front. I also had to unbolt the brake booster to get enough movement to clear the boxes.

While the dash was out, i was able to make sense of the wiring. The ac box has four blower speeds and my non ac box only had 3, so i added the extra circuit for that.
I had to tap the fan ground to trip it on when ac is engaged.
I had to run an ac request line to the ecm, so it can do it's thing, like idling up to compensate for compressor draw.
I had to run power to the control head, so it can control the door motors.

Running the lines and pipes was just nuts and bolts stuff. There's holes for the mounts on all components already,.so it's just a matter of putting it together.

I have yet to install the compressor, so success has yet to be determined! But so far, there are volts where there should be volts and signals where signals go, so, so far so good!