Picked this up today...http://www.homedepot.com/p/GE-7-0-cu-ft-Chest-Freezer-in-White-FCM7SHWW/205462818
to use as a fermentation chamber. I plan on primarily fermenting ales and will most likely use this for about a week- 10 days at a time every other month.
When I'm not using this freezer for fermentation should I be unplugging it? Keeping it open? What about something for dehumidification? Obviously I want to avoid any mildew/mold.
A very popular dehumidifier among homebrewers for their kegerators is the Eva Dry 500. A little bit spendy but they last for many years and work great -- completely worth it IMHO. And if you go to a kegging system it could come in handy. One would keep your empty, unplugged unit perfectly dry.
I keep two of them in my 7.0 cu ft kegerator and even when it is full of kegs (6), it keeps the inside bone dry - free of condensation. I end up recharging the units (takes just few hours) every month or two.