Heater control valve vacuum question

I have not had heat in my car for a few years and am now attempting to solve the problem. My vacuum control module on the blower motor is busted. Tried to repair it but the repair didn't work. My car has factory air. My one heater hose from the heater control valve never gets real hot so I believe the valve is closed. :D

My question is does the heater control valve need constant pull vacuum or can I apply vacuum once and it will remain open. This is more for my understanding than anything else as I did buy a new vacuum control module (if that is even the name) to install at some point. It takes me forever to work on this car cause I'm not a mechanic.

Thanks.

Yes, vacuum has to be applied contnuously to keep the water valve open.

Heat works when I apply continuous vacuum at the heater control valve. Now to pull the entire blower assembly so I may install a new vacuum module. :hurray:

You can put a manual control valve in place of the vacuum one and turn off/on when needed.