Johnson Controls Digital Thermostat Control Unit

[Ghofbrau]

I know it's been discussed here in several threads, but for the novice in me I can't seem to find the answer I need. Just got the unit today, hooked it up to a new chest freezer that I want to use to control fermentation temps. I put the set point at 70 degrees, with the lowest (1) differential. It kicks on when it gets there, but after it is off the temp goes down about 15 degrees! I am clueless, any help?? It would be VERY much appreciated...

Thanks!

 

[day_trippr]

You have the temperature probe dangling in the air inside in empty chest freezer, yes?

When the compressor shuts off the refrigerant is still going to go through its evaporation phase and continue "sucking the heat" out until it reaches equilibrium. Once you fill the freezer with thermal mass and couple the probe to that mass you won't see such drastic over-shoot...

Cheers!

 

[Ghofbrau]

day trippr, thank you. I am racking to secondary tomorrow so I will follow your wisdom once I put it in. I will post the results!

 

[Ghofbrau]

All is well, took your suggestion and after a night in the freezer with the probe attached to the carboy it is perfect. Thanks again, you helped make sense of something that wasn't making sense...

 

[day_trippr]

Excellent. And glad to have helped.
You're going to love the results of true temperature-controlled fermentation...

Cheers!