Temperature controller question (Ranco/Johnson)

[mrgstiffler]

I got a freezer that I'm going to use for fermentation temperature control and had a question about the controller. In the summer, days can get be around 90F, while nights get down to 50F. Do I need a 2 stage controller with a heatwrap of some sort for when it's below my fermentation temp at night? Or will the freezer insulation keep the inside at my specified temperature through out the night?

Say, it's 85F during the day. I have the controller set for 68F and it's just fine. The temperature drops to 55F at night. Will the heat from the fermentation and the insulation of the freezer keep my fermentation temp at 68F?

 

[yogensha]

It will likely be fine. Fill up a fermenter with water and test it first. You may loose a bit but remember fermentation is exothermic.

 

[Catt22]

I agree it will most likely be just fine and the temperature will not drop but maybe a couple of degrees overnight. I had essentially the same setup at one time with the fridge located outside. You can fill a 2 liter PET bottle with hot water and put it in the fridge if it gets too chilly at night. I've never found it necessary to use a two stage controller. Generally it's either heat or cool and sometimes neither is required as the fridge insulation keeps the temps fairly steady. I use a min/max thermometer to monitor the daily variances.

 

[mrgstiffler]

Thanks for the replies! I'd much rather pick up one at my LHBS than order a $120 2 stage from Amazon. Sounds good to me.