lost my hvac level control 97 3.8

I just recently lost my hvac level controls. I have been down this road before but i must have a different problem this time. I have good vacuum lines all the way down to the control. I had a break in a vacuum line last year. I have checked the vacuum line that runs down through the firewall to the control. It holds a vacuum and when the engine is running its creating one. The fuse is also good. The control will still switch to the defrost so that why i now think its a servo (if thats what its called) at the point where it switches from floor to face.

Thanks

Would this be an auto climate control-as in digital readout to set temperature??? If so the vacuum port may have deteriated where it enters the HVAC programmer- losing vacuum there- I have seen 3 or 4 this year do that......

No,

Sorry not enough info, No digital, Circle control