Heater control valve info needed

[DusTed74]

I need a vacuum operated heater control valve, and I'm looking at one of these from Bouchillon's.

http://www.bpeusa.com/BPEheaterValve.asp

The problem is that they want to know if the original one is open-no vacuum or closed-no vacuum, and I do not have one to compare it to.
This is going on a 1974 Dart Sport.
Please let me know if you've got the answer. Its starting to get cold around here. I could really use the defroster.

Thanks in advance....................Ted

 

[67Dart273]

Does your car run? Start and run, and check the hose connection for the valve with heat turned on and off

 

[DusTed74]

OK, I see what your saying.
Test to see when it pulls vacuum, either in the heat or a/c position.
Good call!!
Thanks......................Ted

 

[adriver]

I never remember vacuum off or on.
I marked it on the last one I did but I can't check right now.
I'm guessing vacume to close. But could be wrong.
This is what you get if you go to the store and ask for one.

Maybe this will help.
http://www.forabodiesonly.com/mopar/showthread.php?t=194216