Does manual climate control use any vacuum?

[10fords]

I disconnected all of the vacuum lines on my 1981 240d except the one to the shutoff for the ignition as I have some leaks in the locking circuit. I did this a few months ago while it was hot so I hadn't used the heater or defroster at all, and now my blower motor doesn't come on at all. I checked the fuse and it is fine. Does the system need some sort of vacuum to activate the blower motor? I guess it is possible that the blower motor went tits up, but it worked fine last spring. Any suggestions?