climate control assistance please.

Folks
 
I have an 88 with climate control.
The water valve appears to be controlled by a vacuum switch rather then a cable.
Thing is the valve never opens irrespective of the temperature setting,  (unless I disconnect the vacuum pipe of course).
So is the heater controller stuffed? Or is this related to my inoperative air conditioning since I have climate control?
None operative as in the gas has leaked out, so would this impact the operation of the heater controller?
 
Thanks