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Old 02-23-2011, 01:02 AM   #1
Sep 2010
White Plains, Maryland
Posts: 31
Liked 1 Times on 1 Posts

I am looking for the cheapest solution for an external thermostat I can get to work for a freezer I want to use for lagering in. I may put a tap in it later on, but for now I just want it for ageing beer.

I have been told that you want to make sure the temp reader is not touching anything in side the freezer. I however have no idea where is the best location to put it in the freezer... Bottom... Middle.... Top.... front or back????????????????????????????

HELP ME!!!!!!!!!!!!!!!

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Old 02-23-2011, 01:10 AM   #2
Sep 2009
Posts: 17,765
Liked 1374 Times on 1332 Posts

Johnson analog controllers can be found on ebay on the cheap. Temperature probe can be attached to the back wall, middle shelf area. Some tape them to the fermenter. I suspend mine in the back in freezer gel inside a yeast tube. Helps moderate temp fluctuations.

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Old 02-23-2011, 01:11 AM   #3
Face down on the floor
Mar 2007
Northern VT
Posts: 200

I believe closer to the top would be best but if you are really concerned you could mount a little cpu case fan inside there to move the air around in there but I doubt you would need that. Like you said just keep it from resting on the inside metal.
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Old 02-23-2011, 01:40 AM   #4
Jan 2009
Posts: 4,998
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IMO & IME, the optimum placement for the controller probe depends on if you are using a fan or not. When not using a fan, the best location is near the bottom of the freezer and not touching the wall. OTOH, if you are using a fan, then the optimum location is directly in the air stream of the fan and it doesn't make a lot of difference where the fan is located so long as it can keep the air moving throughout the freezer. The larger case fans work better than the very tiny ones and running the fan continuously works better than intermittently. I think that placing the probe in a container of water or a gel pack is a bad idea. Doing so just widens the temperature swing and if the container is large enough, this could cause big time over/undershooting the temps. There are move than a few variables interacting, such as the size of the freezer, how full it is, whether or not you use a fan, whether or not your controller has an adjustable differential etc, etc. As I said at the beginning, this is JMO based on some crude trial and error testing. A Kill-A-Watt meter thingy is very handy to check the power consumption when trying various configurations. When doing so, be sure to allow plenty of time for everything to equalize when making changes. Sometimes this can be more than just waiting overnight and especially so if you have a lot of full kegs or fermenters in the freezer. YMMV...blah...blah.

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Old 02-23-2011, 05:24 AM   #5
Jan 2010
Posts: 230
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could someone please reference the part numbers from the Johnson Controls temp controller?

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Old 02-23-2011, 05:32 AM   #6
Good for what ales you
Jul 2008
, Southwest Iowa
Posts: 648
Liked 37 Times on 29 Posts

It's hard to beat the price on these:


There are prior threads here about setting them up and programming them.

Reason: found a cheaper one

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Old 02-23-2011, 06:36 AM   #7
Nov 2009
Edmonton, AB
Posts: 98
Liked 1 Times on 1 Posts

Check a local greenhouse supply store. That's where I got mine and I couldn't find it anywhere else. It was $70, has a plug in and a piggyback built into it. All you have to do is plug the freezer into it, plug it into the wall, set the temp, and place the module inside the freezer.

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Old 02-23-2011, 07:07 AM   #8
LVBen's Avatar
Jan 2010
Las Vegas, NV
Posts: 1,343
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Originally Posted by Reelale View Post
Some tape them to the fermenter.
Yep, I tape mine to one of the buckets!

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Old 02-23-2011, 12:29 PM   #9
rekoob's Avatar
Feb 2011
Norfolk, VA
Posts: 1,429
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I just drapped mine over the carboy neck or the keg handle and let the probe hang about a third of the way down. Seems to have worked pretty good. My chest freezer is only a small 2' x 2' so the small size might be more of a factor then anything else. I just converted it to a keezer (not sure what I'm going to do about fermentation chamber) and will be able to just fit four kegs inside. Not sure what I will do with the probe now but after I get all the lines run if it's getting in the way I will have to figure something out.

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