Wonder, glad you got it figure out, but a question for ya - if you have access to that cold of air, what are you doing running the AC in the dead of winter for?
Not sure if for security reasons it's a necessity, but simply for the power savings I'd have to investigate ways to use that cold air.
I'm loving the temps of ~50F in my garage right now - I can lock in whatever temp I want in my tent to the degree.
Other then that grow's looking great; I'd comment more but vertical growing is above my pay grade (and I'm kinda jealous)