Problem with my new temp controller...

[Beavdowg]

I hooked up my new A419 digital temp controller to my chest freezer last weekend and set it for 41*F. I set the differential to 3 degrees. The thing that concerns me is that several times I've gone out in my garage to check it and it'll say the freezer temp is 36*F. One time I checked it and it said the temp was 41*F and the freezer just kicked on as I was watching it. My understanding is that it shouldn't kick on until the freezer temp was 3*(in this case) above the set point and then it would only stay on until the temp got down to 3* below the set point. What is going on here or do I have it all wrong?

Thanks

 

[Ohio-Ed]

One thing I learned is that your freezer will continue to cool after the A419 shuts the power off. If you watch a thermometer, the temp till continue to go down after the power is shut off. So thats where the 36f came from. I think you'll have to learn how much your freezer will continue to cool and set your temps accordingly.

I don't remember if the diff (3F) can be changed to be relative to the on vs off or not (but I'm sure an expert will chime in here shortly)

 

[Scimmia]

There are two options on the 419, cut in at set point and cut out at set point. You're set to cut in at set point, which means it turns on at the temp you have it set at and cools until it's beyond the differential. In this case, it will cut in at 41F and cool until it gets to 37F. Seeing 36F won't be uncommon at all, as the coils are still cold when it shuts off and will cool a bit more. Everything is working exactly as it should.