InkBird ITC-308 with Fermentation Chamber Question??

[BigEasy43]

So I am using a freezer as an Fermentation Chamber for the first time and have it hooked up to the InkBird ITC-308. I currently have the temp set at 67F with a 1F difference for Heat and Cool. The Freezer will cool the chamber to 67F and shut off, but as you know the freezer will still cool because of the cold air inside. So what happens is the freezer(Even though shut off) is still cooling and drops the temp below 66F within 5-10mins and then starts to heat again, so it seems like a very quick cycle. I understand it's only 1F on either side, but would like to keep the temp as stable as I can. My question is, should I set the Heat temp lower than 66F? Will this cause an issue? Or should I just leave it the way it is? Any help would be great.

 

[doug293cz]

Where is your temp probe? Taping the probe to the side of the fermenter with a little insulation on the outside of the probe evens out the temp fluctuations, and greatly reduces the temp swings to the controller. This works because you get a weighted average temp reading between the fermenter and the chamber, which keeps the chamber from undershooting the temp as far, and the thermal mass of the fermenter, keeps the input to the controller from dropping as far as the chamber temp does. This reduces the tendency to undershoot when cooling and overshoot when heating, reducing the overall cycling of the compressor and heater.

Brew on

 

[mongoose33]

Here's how I do that in mine. It's a little hard to see the temperature probe but I cut a very thin slot in the piece of blue foam to cradle the temp probe, then I keep both against the side of the fermenter with a bungee cord.

I use a fridge not a freezer but the idea is the same. The air inside the refrigerator or freezer can vary a fair amount, but the temperature of the wort is relatively stable.

 

[Morrey]

As Doug advises above, protecting the 308's probe from ambient air is key. I often tape the probe to the fermenter with blue painters tape, then cover the probe with a beer coozie held on by a second strip of tape. Or Mongoose33's idea with a bungee cord is even better.

Ideally, I have outfitted most all of my fermenters with thermowell's that get a reading from the center of the wort. Depending on the style of fermenter you use, they are easy to install and make the 308 work much more efficiently.

In my climate (SC), I don't use a heat belt this time of year. I set the freezer temp with the 308 and use a 1 degree cooling hysteresis/swing. Even though the heat indicator may be illuminated at times, if nothing is plugged in, nothing is applying to heat the unit. In the winter I set the heat at 1 degree and the cool to 2 or 3 degrees hysterisis. I do this so the heat/cool doesn't shift back and forth rapidly.

 

[BigEasy43]

Where is your temp probe? Taping the probe to the side of the fermenter with a little insulation on the outside of the probe evens out the temp fluctuations, and greatly reduces the temp swings to the controller. This works because you get a weighted average temp reading between the fermenter and the chamber, which keeps the chamber from undershooting the temp as far, and the thermal mass of the fermenter, keeps the input to the controller from dropping as far as the chamber temp does. This reduces the tendency to undershoot when cooling and overshoot when heating, reducing the overall cycling of the compressor and heater.

Brew on

My temp probe is taped to the side of my bucket with a sock folded up to act as insulation. Should I be using something else?

 

[mongoose33]

My temp probe is taped to the side of my bucket with a sock folded up to act as insulation. Should I be using something else?

It depends on how thick the sock is and how much you have compressed it. Insulation like that depends on trapped air spaces to slow the transfer of heat. IMO, you'd want about an inch of insulation over the probe, and on either side of it, above and below. If the sock is loosely folded and you have an inch or more of space around the probe in all directions, it's probably fine.

If not, you might try a piece of styrofoam you have lying around. Everything in a box these days seems to come packed in styrofoam. A 1" thick piece of that (or more) with a small channel carved out for the probe so the foam conforms to the bucket will work well.

 

[BigEasy43]

It depends on how thick the sock is and how much you have compressed it. Insulation like that depends on trapped air spaces to slow the transfer of heat. IMO, you'd want about an inch of insulation over the probe, and on either side of it, above and below. If the sock is loosely folded and you have an inch or more of space around the probe in all directions, it's probably fine.

If not, you might try a piece of styrofoam you have lying around. Everything in a box these days seems to come packed in styrofoam. A 1" thick piece of that (or more) with a small channel carved out for the probe so the foam conforms to the bucket will work well.

So I took a piece a styrofoam and carved out a small channel and put it back on my bucket and it has made a WORLD of difference in temp. It seems to be steady at 67.6F which is awesome. Thanks for the idea and the pic which helped.

 

[Shepbrew]

Opening up your heat differential from 1F to 3F would help with cycling also. The fermentation is giving off enough heat where unless your ambient is very cold your heater will hardly ever (maybe never?) kick on if using the insulation taped to the side as others have mentioned.

The only time my heater ever kicks on is when I'm purposely ramping up the temperature near the end of the ferment.