Mainly get moisture when warm air hits cold parts, in this case its cold air hitting hot parts. I duct a 5000 btu window unit right into my cards and have no problem "other than my electric bill".
What's a 5000 btu window?
I guess it's an aircon.
However I believe that cooling air with an evaporative air cooler is much more energy efficient.
Or a combination if you care for comfort.