I am not home yet but playing devil's advocate what could be the problem if inlet and outlet are not hot? I know it can't be heater core that is brand new. Could it be a thermostat even though the truck isn't overheating?
No different door. this model actually has two a panel/floor door, and a floor defrost door, they are located after the blend door. They are vacuum operated so make sure no vacuum line are undone.
Here is a picture of the vacuum actuator and you can see parts 3 ad 4 are connected to the door that is onside the box, you most likely wont see the door itself, so locate the vacuum actuators and the doors are in that area of the box.
Matt, I have vehicle again now. Do you have a diaghram of the complete system with all the blend doors? I am getting heat only right underneath the heater core. I do know that the temperature (hot /cold door is working properly when I rotate the dial. there is another switch right under the control unit that I can manually move but it still doesn't give me heat through the vents.
Hi here is a picture that shows the switches and all vacuum lines, and colors going to each door.