Originally Posted by springer
I'm confused here. If you have a refrigerator/freezer compo why would you need the Johnson control in the first place? The control is only used to raise the temp in chest or upright freezer as the thermostat highest setting is well below freezing temps.
Probably because he wants it to control the temp more precisely for fermentation. Most refrigerators don't go up 50°F, much less 54°-59°F for fermenting lagers.
Used purely in a storage and dispensing capacity, a fridge would work fine but for temp. control for fermentation it needs additional temp control.
To answer the OP's question, yes it will mess with your freezer and you probably shouldn't keep food in it. Or, better yet, buy a brew belt and use that with the temp controller.