help with temp controller

[tmac2050]

I'm fermenting with temperature control for the first time and need some help.

I've set up a chest freezer with a A421 temp controller with a FermWrap inside for heating in my cold winter basement. Freezer is not currently plugged in (will switch from heater to freezer when summer comes, or I want to lager)

I set the controller with the following, and the temp shot up to 73. Shoudn't the controller have shut off the heating pad as soon as it got up to 62?

Off = 62
On = 60
SF = 1
ASD = 1

Thanks.

 

[day_trippr]

Where did you locate the temperature probe? And do you have anything "stirring" the air inside the freezer?
An empty freezer will be difficult to control, especially just dangling a controller probe in the air. Had this been summer and you were running the freezer compressor you'd be wondering why the temperature over-shot below your Set Point.

You need thermal mass to flatten spikes, a better way to track the temperature that is important (in this case, the fermenting wort temperature), and it's a good idea to have a small fan running to break up thermal stratification.


Take one of your fermentors, fill it with a decent amount of water, strap your controller probe to the side of it under a good insulator (inch thick packing foam is excellent) and pin it there with some kind of strap (I use 2" wide velcro straps I stumbled upon in a Lowes about 15 years ago). Then see how your controller responds once everything has reached equilibrium...

Cheers!

 

[Transamguy77]

I agree with Day Tripper on the stagnant air. Did the controller read 73? Or was that the temp on a different thermometer in the chamber? If the probe temp doesn't change the controller won't know to turn off.

 

[tmac2050]

Thanks for the feedback - I'll try those recommendations.