Messed question

[johnsonbrew]

I just got my Johnson's Control thermostat for my keezer and the instructions say turn your refridgerator to the coldest setting. Is this the same for a freezer or do i need it on the warmest setting for the freezer?

 

[worksnorth]

I've got mine turned to the warmest setting. Found that with it on the colder settings it would over run the temp setting of the Johnson controler and get to cold.

 

[johnsonbrew]

That's what I was figuring, seems counter productive to use the coldest setting in a freezer

 

[skipper1953]

I've got mine turned to the warmest setting. Found that with it on the colder settings it would over run the temp setting of the Johnson controler and get to cold.

How is your Johnson controller wired to make that possible? If the Johnson turns off the power to the built in temp control and the compressor, it should get no colder than the Johnson calls for. On the other hand, with the built in controller set to warmest, the compressor could be turned off before the Johnson tells it to turn off. It should make no difference if you are controlling a freezer or a fridge.

 

[johnsonbrew]

After plugging in the Johnson and having it set at 38 degrees, the temp in my freezer went down to 33 degrees right away I know there is some variance but that is 4 degrees in a short 20 minute period or so

 

[skipper1953]

The location of the temperature sensor can have an affect on the function of the temperature controller. Without forced air circulation the air in the center of the appliance can be warmer than the air nearest the walls.

Hang out with your freezer/fridge for a couple of cooling cycles. Listen for when the compressor cycles on and off. Note what the temperature is at those times. Chances are that the Johnson controller is turning the compressor off at the set temperature and the interior temperature of the appliance is "coasting" down a bit before stabilizing and then beginning to rise again and triggering another cooling cycle.

This seems to me to be the most likely explanation for what you are seeing. I've been told I was wrong before but I think I was only mistaken.

 

[badbrew]

Something's fishy. I hope you have a separate thermometer in the freezer and are not gauging the temp by the johnson. Also, don't let the probe touch anything unless you want to bury it in a media.

Leave the freezer on high and have sp at 38 and diff at 5 or whatever. That will turn the unit on at 38 and off at 33. It should leave the freezer temp at 38. Also an empty freezer will do funny things. Fill it with kegs of water (beer is better :fro to play with it accurately.

 

[johnsonbrew]

There is only one dial on the thermost, I made sure the sensor was not against the wall and more in the center of the freezer and moved the thermometer away from the walls as well. Since beer does have some alcohol in it, what is the approxamate freezing temp of beer, I like my beer cold and was shooting for about 37/38 degrees in the keezer. This up and down thing is driving me crazy.

 

[skipper1953]

As badbrew suggested, fill your freezer with as many full kegs as you have or will fit. If you don't have beer to fill them with, use water. Just be sure they are filled. This increased mass will go a long way towards stabilizing the internal temperature of your freezer.

The differential setting of 5 degrees is going to cause a fluctuation of 5 degrees at the very least. If you decrease the differential setting you should decrease the amount fluctuation. However, you will also increase the frequency of cooling cycles (to the extent that the anti-short cycle setting will allow). In a day or two the temperature will stabilize and cycling will be minimized. A chest freezer will allow you to use a lower differential value with less impact on the cooling cycle frequency than an upright freezer.

The best way to stabilize the temperature in your freezer is to set the controller with your preferred values, keep the freezer filled with as many full kegs as possible and keep the lid closed.

Edit:
The water in beer freezes at 32 degrees fahrenheit.
Set the built in temp control to the highest (coldest) setting to ensure the external controller is doing the controlling.