A/C Heat help

[70cobrascj]

Trying to figure out how the heat works on a A/C equipped car.
I have basically a whole new system, new heater core, new heater A/C box, new water valve vacuum motor. I have the hose off the block with the valve on the heater core tube to the right and the valve is installed with the arrow pointing towards the firewall. The hose coming off the water pump on the heater core tube to the left like what I feel is correct.
Before I installed the water valve vacuum motor I noticed you have to have the diaphragm pulled in like it would be with vacuum applied to it for water to flow. Am I correct?
What is confusing is the water valve switch attached the the hear core box. Does it send vacuum to the water valve when the temp control arm is in the cold position ( pushing on the switch plunger) or in the warm position not pushing on the switch plunger?
With the car fully warmed up and idling and trying to get heat on in the car it seems like I have the temp set on cold and the heat A/C selector in fresh or A/C to get vacuum to the water valve.
Any insight would be greatly appreciated
Thanks

 

[Hemikiller]

The valve is to shut off the hot water flow to the core when the temp selector is in the Cold position. The cable end pushes on the vacuum switch on the box, which opens and applies vacuum to close the valve. IIRC, there are normally open and normally closed water valves. Yours should be open with no vacuum.

There's a diagram in the shop manual that shows where vacuum is applied in each position of the control.

 

[70cobrascj]

The valve is to shut off the hot water flow to the core when the temp selector is in the Cold position. The cable end pushes on the vacuum switch on the box, which opens and applies vacuum to close the valve. IIRC, there are normally open and normally closed water valves. Yours should be open with no vacuum.

There's a diagram in the shop manual that shows where vacuum is applied in each position of the control.

Thanks that is what I was thinking. It bums me out because now I have anti freeze in the line and I’ll have to try to not make a mess with swapping it out.
Would you know of a correct one.
I’m 99.9 percent mine is normally closed.
Thanks

 

[Hemikiller]

This is the one I have on my Cougar and Country Squire.

https://www.amazon.com/gp/product/B003R33QZS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[70cobrascj]

This is the one I have on my Cougar and Country Squire.

https://www.amazon.com/gp/product/B003R33QZS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I ordered that one from Summit
NPD sure is pricey on that item.
Summit list both the 1021C and the 1022C for 13 bucks. NPD 35 big ones

 

[Doug's 73 Mach1]

Here is the diagram out of the 73 shop manual. As mentioned already the valve in the engine compartment should be normally open. Vacuum should close it when the temp lever is moved all the way to cool. The temp control cable connects to a pivoting arm, the arm pushing the water valve vacuum switch open letting vacuum reach the valve in the engine compartment and closing it. The cable needs to be adjusted correctly to do this via the clamp near its end. With the engine running you should be able to see the valve in the engine compartment cycle from open to closed and visa versa when the temperature control lever is moved to cool and away from cool. This assumes the cable is adjusted correctly and the vacuum system is connected correctly and functioning as it should.

 

[rhigg1959]

Just as a follow up with this thread, I had a firewall out Classic auto air kit installed. It worked fine for a short period, then started
blowing hot air. I determined that the water valve, which a new valve was installed when the kit was, was the culprit. It was not completely closing the hot water off. I replaced with another valve and again, had the same issue. I was intalling the normally open valve. To remedy the problem, I ordered a manual water valuve from Amazon and installed and it fixed the issue. Instead of installing a choke cable to operate it from inside the car, I will manually open the valve in the winter.

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