HVAC Control Problem

[bcudachris]

Hey guys, I put this in the interior section since it is creature comfort related, but mods please move as necessary.

Not too long ago I rebuilt my A/C box as part of a larger project.  Now everything is up and running and it blows ice cold.

Only problems is I think I swapped a couple of vac lines on the box.

When in the "Off" position, I get cowl air coming through the AC ducts like a vent
The "Max A/C" and "A/C" button functions are reversed - A/C setting blows recirc air and the reverse.
"Defrost" and "Heat" seem fine, but I haven't checked if they are pulling fresh or recirc air

I believe I just have the fresh air door vac lines swapped.  I was careful to number them with tape and take pictures on disassembly, but I clearly didn't get something right on reassembly.

Anybody with knowledge of these things able to confirm my conclusion from troubleshooting? and/or point me in the right direction?

This is in a 73 Barracuda

Thanks
Chris

[1 Wild R/T]

This may help...

[bcudachris]

Thanks for that, very helpful.  The troubleshooting guide in the shop manual indicates that I have the fresh air door actuator lines backwards.  Hopefully I can get to those without too much trouble.  If not, I can probably switch the tubes at the controller.

[bcudachris]

So, turns out my supply line appeared to be in good shape but sucked air pretty over pretty much 2/3 of the run.  Replaced and cold air door working properly now.  Unfortunately, none of the other doors move now and air comes out all of the ducts no matter the setting.  Time to work backwards from the switch...

[70 Challenger Lover]

Vacuum actuated stuff can be a real pain.

[bcudachris]

Switch is basically its own internal vacuum leak at this point.  Air comes out every duct in and under the dash at all times no matter what the setting.  Testing it with a hand vac pump confirmed.

Used the hand vac pump to check all the actuators on the box from the plug.  The fresh air door close actuator is a little slow and hisses, but everything functions as it should more than a year after my rebuild job, with just a hand pump, so pleased with that.

I ordered the OER repop switch, we'll see how it does.  I like the OER paint, though I dispute the accuracy of some of their colors.  Their fuel senders I had were both junk so I'm hoping the switch is not.

I'll close the loop here when I get the new part installed.

[Chaos-N-Mayhem]

Have to ask what paint were you referring to in your post?

[bcudachris]

Specifically 444 Green interior paint.  The color is darker and a different hue of green than original.

Went around with Classic Industries on it (they were great).  Classic did their homework and tested 3 cans from three lots in their supply and agreed with me that the color was off.  They went back to OER, got back to me and said we agree, but it is what it is and sent me another can.

I actually like the color better, so ultimately bought a few more cans.  I've refinished everything but the door and rear panels.  Will get to that.

[bcudachris]

Ok, so switch and source check valve replaced. Everything worked great for a couple of days. Now the close side of the fresh air door actuator and the heat side of the heat/AC actuator aren't able to work at all without assistance. If you start manually actuating the doors, they will finish the job for you. The fresh air door was known to be iffy (hissing and took a long time to actuate) but the heat/ac actuator thing is new.

Anybody know how to fix these things or know of a vendor that sells or repairs them?

I've contacted Original Air Group, we'll see.

Thanks.

[bcudachris]

Also, is anyone with a parts catalog able to post p/n's for the ac box vacuum actuators? or direct me to where I can find the part numbers?

Thanks
Chris

[1 Wild R/T]

The same heater box was used in lots of 2 & 4 dr B bodies from 71-74 so all E bodies with A/C & all 71-74 B bodies with A/C... Those parts aren't hard to come by... & honestly most of the diaphragms test good... Apparently you just have bad luck...

[bcudachris]

No doubt, on the bad luck they both tested out OK a year and a half ago when I had it out. One hissed a little when it 1st started moving, but functioned and the other functioned perfectly.





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[Shoooter]

I have a AC car and I'm having a problem with the blower motor.i hooked up power and now when the key is on the blower motor will run. I cant shut it off and it wont change speed?

[bcudachris]

Sounds like its hooked up to key-on power and bypassing the electrical switches in the control unit.  Schematics and a multimeter will be your friends running that down.  I suspect if somebody jumped the fan control though, there might be some other problem.  Does the A/C clutch engage properly?

[Shoooter]

I have no ac parts that are under the hood. I'm searching for them. As of right now there is just the AC parts inside the car.