Got the Holiday 5cu ft chest freezer from Lowe's for my kegs and bombers and I hooked up a Johnson Digital Temp Controller to it.
I originally had the probe just hanging in the air and it seemed like the compressor was turning on too frequently. So I then taped it to the side of a water bottle between a piece of insulation foam hoping to get more of a constant temp of the water in the bottle, but again it seemed to turn on the compressor too much.
Both ways I had it set to 40 with a differential of 5 so that it would stay between 40-45degrees in the freezer, but once it hit 40 it wouldn't take too long before it hit 45 again.
So I took another step and took a gatorade bottle and put a thermowell in the cap and inserted the probe so I could take the core temp of the water in the gatorade bottle.
The probe says it is not waterproof which is why I used the thermowell.
Now I have run into another problem, I have my controller set to "cut out" at 41degrees with a differential of 3. So when it hits 45degrees the compressor turns on and should turn off when it hits 41.
It does turn off when it gets to 41, but the water temp continues to drop and goes down to around 38degrees.
My thought is that it is getting it so cold in there that when the water temp gets to 41 and the compressor turns off, it is still so cold that it makes it drop another 3 degrees. It wouldn't happen when I was measure just the air because it takes less energy for the cooler to drop the air temp then the water temp in the bottle.
From other people's experience, should I just compensate for that 3 degree drop and say set my controller to 43degrees with a differential of 1, so that way it will stay between 40-45 in the chest freezer?
I want to minimize the compressor cycles as much as possible to help prolong the life of the freezer.