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Johnson temp controller

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When using a freezer with a controller, what is the best "temp" to set the freezers temperature gauge.

I've read some push it all the way, as cold as it could possibly get, while others dial in the middle of the range, or on the low side.

Using an auxiliary controller, is there a difference in where the stock temperature dial is set?
 
ultravista said:
When using a freezer with a controller, what is the best "temp" to set the freezers temperature gauge.

I've read some push it all the way, as cold as it could possibly get, while others dial in the middle of the range, or on the low side.

Using an auxiliary controller, is there a difference in where the stock temperature dial is set?

For the majority of freezers that have a simple on/off thermostat, you want to set it on max to be "always on". Your auxiliary controller should be the thing powering the fridge on and off, and you don't it to be fighting with an internal thermostat.
 
For the majority of freezers that have a simple on/off thermostat, you want to set it on max to be "always on". Your auxiliary controller should be the thing powering the fridge on and off, and you don't it to be fighting with an internal thermostat.

MalFet, I just pulled my carboy out for a Diacetal Rest. I put a 5 Gallon Carboy full of water in there and taped the thermocouple to the bottle.

Last I looked after putting it in the temp was about 62 degrees. I have the controller set for 50. We'll see what happens.

I'll start a new thread if I see anything interesting. Sorry for the Hijack. :mug:
 
MalFet, the bottle is now down to 45 Degrees with no cycle. It definitely works well. It definitely didn't behave as I expected.

I measured the bottle temp and the water temp at the same time. The water was about 10 to 12 degrees behind the temperature of the Glass carboy.

The water is now down to about 50, so 5 degrees behind. The fridge was very cold, my digital thermometer couldn't read it. I did have a analog in there but it went below zero and wound back around to 250degrees on the dial so I don't know how cold it got.

The lag between the liquid temp and the bottle temp may have stabilized it. When the freezer turned off the cold was still being absorbed by the liquid and bottle.

In any event, I'll be using this method now. Thanks for suggesting this.
 
MalFet, the bottle is now down to 45 Degrees with no cycle. It definitely works well. It definitely didn't behave as I expected.

I measured the bottle temp and the water temp at the same time. The water was about 10 to 12 degrees behind the temperature of the Glass carboy.

The water is now down to about 50, so 5 degrees behind. The fridge was very cold, my digital thermometer couldn't read it. I did have a analog in there but it went below zero and wound back around to 250degrees on the dial so I don't know how cold it got.

The lag between the liquid temp and the bottle temp may have stabilized it. When the freezer turned off the cold was still being absorbed by the liquid and bottle.

In any event, I'll be using this method now. Thanks for suggesting this.

Very interesting. I'm glad the liquid stayed stable, but I'm surprised by how much difference there was with the carboy surface. Thanks for doing the science. I definitely learned something new! :mug:
 
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