Temp controller fluctuations?

[brewhoo]

I have an ink bird attached to a deep freeze and am getting temp fluctuations between 67-69F. I have the temp probe attached to the side of the carboy and insulation wrapped around that area so as to get a reading of the fermenter. When the freezer kicks on it seems to be kicking on just a little too long and instead of just taking the fermenter to 68, it hits 67.

Is this 2deg temp fluc an issue?

If I'm running multiple fermenters in the same freezer should they all be pretty much the same temp or is one going to be wildly off from another?

Should I simply let the probe free float and if so what temp should I set at to assure the brew is at 68?

 

[Young953]

I have the same controller, and i found the same temp fluctuation issues with taping the probe to the side of the carboys.
I found a huge improvement when i got some thermowells to actually measure the internal temp of the liquid. The controller will kick on as normal, but it doesn't take that drop below my set temp anymore. i also think i'm getting a more accurate reading since the temp of the glass fluctuates more than the actual liquid.

 

[brewhoo]

I have the same controller, and i found the same temp fluctuation issues with taping the probe to the side of the carboys.
I found a huge improvement when i got some thermowells to actually measure the internal temp of the liquid. The controller will kick on as normal, but it doesn't take that drop below my set temp anymore. i also think i'm getting a more accurate reading since the temp of the glass fluctuates more than the actual liquid.

So do you have the thermowells rigged up to a temp monitor of some kind and if so what are you using? Or, did you change the probe on the inkbird and run that directly in the brew now?

 

[Young953]

the thermowell is just a stainless tube that is connected to a carboy stopper, and the temp probe from the inkbird slides right inside the tubing. the tube is crimped at the end, so no need to change anything with the inkbird probe. I found my setup at MoreBeer

 

[BryceL]

2 degree fluctuation should be fine. If your controller turns on and off every time it drops a degree it will put extra wear and tear on your freezer compressor. But also like stated above, a thermowell would be ideal for getting the most accurate temperature readings of your beer.

 

[petrolSpice]

After the compressor stops the inside of the freezer is still very cold so the temp will continue to drop. If that's a 2-stage controller then get a heat wrap also.

I use an STC-1000 to control the chest freezer and heat wrap and it keeps the temp within 0.6C of the set point. I also use a thermowell to get the temp at the center of the fermenter.