Heater valve question

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Joined
Dec 11, 2015
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Location
Philadelphia
My Car
73 Mach 1
My car was a factory AC car that has since been deleted. I've removed a lot of the old sensor and vacuum lines that are no longer needed with my EFI setup. My question is, is there a valve I can put inline with the heater core lines that would keep my heater core from cooking my out in the summer? In the same respect I'd like to be able to still have the ability to warm up the inside as the fall weather sets in. So basically have a valve I can turn under the hood to divert coolant from the heater core until I want it when the weather gets cooler.

 
My car was a factory AC car that has since been deleted. I've removed a lot of the old sensor and vacuum lines that are no longer needed with my EFI setup. My question is, is there a valve I can put inline with the heater core lines that would keep my heater core from cooking my out in the summer? In the same respect I'd like to be able to still have the ability to warm up the inside as the fall weather sets in. So basically have a valve I can turn under the hood to divert coolant from the heater core until I want it when the weather gets cooler.
It is a heater control valve. It is vacuum activated, came stock on the car. Chuck

 
My car was a factory AC car that has since been deleted. I've removed a lot of the old sensor and vacuum lines that are no longer needed with my EFI setup. My question is, is there a valve I can put inline with the heater core lines that would keep my heater core from cooking my out in the summer? In the same respect I'd like to be able to still have the ability to warm up the inside as the fall weather sets in. So basically have a valve I can turn under the hood to divert coolant from the heater core until I want it when the weather gets cooler.
It is a heater control valve. It is vacuum activated, came stock on the car. Chuck
Where does it get its vacuum from? The only vac line I planned to connect it from the intake to the carb and the valve cover to the intake.

 
With AC you had a vacuum control valve in the heater hose under the hood. Vacuum hose diagrams should be here on the site. Here is a pic of an original set up. You can see the vacuum line goes through the firewall to the inside and is part of the heater AC controls. Vacuum line diagram will show which one.



 
The vac line is still there from the firewall. My question is if nothing else is connected with the AC system and I slide the inside lever to cold will the valve under the hood close or does the AC actually have to be on. If AC has to be on then that factory heater valve is won't work for me.

 
You could always put in a manual valve that will work with a cable... or not.

Come summer just open the hood and turn it off.

Bru



 
That is a factory style valve it will work fine.  It is what my AC system uses to shut off the heat.  The entire circuit is a bypass circuit, closing it off hurts nothing to my knowledge
+1

Mine was an AC car but removed. I have a factory style, vacuum heater valve installed and use the existing controls to control heat, fan speed, and floor, vent, defrost just fine.

 
Vacuum comes from the intake manifold through the fire wall to the cool/heat lever. When the lever is moved to the heat position the vacuum is sent to the valve under the hood, opening the valve allowing heated coolant into the heater core. Chuck

 
Vacuum comes from the intake manifold through the fire wall to the cool/heat lever. When the lever is moved to the heat position the vacuum is sent to the valve under the hood, opening the valve allowing heated coolant into the heater core. Chuck
This would create a problem for me because I wouldn't have anything coming off the intake for that. I think I remember that heat sensor that was in the water pump (maybe) that had the vacuum connections on it. I removed those sensors. Looking for an alternative non factory was I guess.

 
So I dug this up. Could I just install this and turn it to allow coolant to flow into the core when the weather gets cold? If that is the case which hose am I putting in line with? The one coming off the pump or the engine? In the same respect is it pump to lower hole on the firewall and top to block? Thanks

https://www.summitracing.com/parts/fss-74828?seid=srese1&gclid=CL2E5_b108gCFUM2gQod7IoF9A
That should work fine.   Install it in the line from the manifold to the heater core.  The return line goes to the water pump.  Since the heater core lays flat it doesn't really matter which side of the core you use as the inlet or outlet.  If the core was on it side with one tube above the other you would want to put the inlet hose to the bottom tube.  That forces the air out of the core.

 
Vacuum comes from the intake manifold through the fire wall to the cool/heat lever. When the lever is moved to the heat position the vacuum is sent to the valve under the hood, opening the valve allowing heated coolant into the heater core. Chuck
I believe vacuum closes the heater valve, thought I saw that in the shop manual.

 
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