Fermentation fridge + ranco notes

Rezzin · Post by **Rezzin** » Tue Apr 08, 2008 2:39 pm

Since I made the jump to all grain 2 years ago, I've been fermenting all of my beers in a fridge I picked up off craigslist using a Johnson controller. I simply left the probe laying in the bottom corner. I would adjust the ambient temp anywhere 6-10d below my target temp depending on how the primary was doing. I've always managed to keep my temps fairly accurate throughout the fermentation process (never off by more than 1-2d or so) but it did take a lot of checking and adjusting. I had grown used to it.

I recently picked up a ranco controller and this time I decided to try taping the probe to the side of the fermenter. I just folded over a paper towel sheet, then taped the probe to the side of the carboy (I'm using a Better Bottle). I have a 1d differential set. It seems to be working just fine as long as I set the ferment temp 1d lower than my target. I'm using the sticker fermometer to check temps as well. Ranco reads 63, the fermometer reads 64-65 (i've always had trouble figuring out the colors but 64 is blue and 66 is brown so I figure thats 64-65). I'm pretty sure some of the ambient cold is 'leaking' through the paper towel and skewing the reading just a tad. Not a big deal.

The nice thing is, I don't have to baby sit this thing anymore. I used to wonder if the ambient temp would drop too low, causing the fermenting beer to also drop lower than I wanted but this doesn't appear to be the case at all. The next time around I'll use a better insulator to cover the sensor and see if this puts me right where I want to be.

Just figured I'd share this in case anyone was every planning on doing the same.

BrewMasterBrad · Post by **BrewMasterBrad** » Tue Apr 08, 2008 3:16 pm

I've always used a thermowell stopper in my carboys using the Ranco controller. I set my differential to 1 degree and it seems to work well. As long as you are insulating the probe, the external application should work just as well. Using a temp controller was one of the best thing I ever did to improve the quality of my beer too.

maltbarley · Post by **maltbarley** » Tue Apr 08, 2008 3:26 pm

I just started with refrigeration controlled fermenting and simply taped the temp probe to the side of the fermenter with blue masking tape. Using a fermometer as well, i'm having the same results as you, Mike. At some point I plan to use a thermowell. I just wish I had this stuff for my previous couple of batches.

As a side note, if anyone plans to build a cold box, Costco has a nice window A/C right now for $50 after the $20 rebate.

dhempy · Post by **dhempy** » Wed Apr 09, 2008 11:18 am

I use a SS thermowell stopper as well when fermenting (previously in my ferm chamber .. soon in my ferm fridge).

But another thought is to build a permanent set up like I did for my kegerator. Basically I took a 2 plastic jug, made a copper thermowell in the top, and set it in the bottom of the kegerator. 2 qt will change temps faster than kegs BUT is more stable than air so the freezer doesn't kick on/off as freqently. Now for fermenting, a thermowell in the vessel is best, but this provides another (cheap) option.

Dan

maltbarley · Post by **maltbarley** » Thu Aug 28, 2008 3:17 pm

Mike, get yourself a thermowell.

I picked one up a couple weeks ago and finally got to use it with the brew-day batch. I was surprised to see quite a difference in temps between what my thermowell shows and what the fermometer shows on the outside of my fermenter. Previously, the taped on probe was very close to the fermometer reading. YMMV

Rezzin · Post by **Rezzin** » Thu Aug 28, 2008 3:23 pm

maltbarley wrote:Mike, get yourself a thermowell.

I picked one up a couple weeks ago and finally got to use it with the brew-day batch. I was surprised to see quite a difference in temps between what my thermowell shows and what the fermometer shows on the outside of my fermenter. Previously, the taped on probe was very close to the fermometer reading. YMMV

Really? How much difference are we talking about here?

maltbarley · Post by **maltbarley** » Thu Aug 28, 2008 4:36 pm

I was seeing about about a 6 degree difference. The thermowell temp was 61 and the fermometer temp was 66-68.

Rezzin · Post by **Rezzin** » Thu Aug 28, 2008 4:54 pm

maltbarley wrote:I was seeing about about a 6 degree difference. The thermowell temp was 61 and the fermometer temp was 66-68.

WOW - 6 degree difference?

I always figured with all that movement, the temperature would be somewhat consistent within a degree or two but I guess I was wrong. You are fermenting in a carboy right? I also would have thought that maybe the thermowell would register higher temps since it's sitting in the middle.

Btw, when you noticed these temps, what did you have your ranco set for as the desired temp?

Does anyone else with a thermowell notice the same thing?

dhempy · Post by **dhempy** » Thu Aug 28, 2008 5:46 pm

Haven't paid attention .. luckily I've got a batch fermenting now in my ferm freezer ... it is likely past the main endothermic stage. I'll check and post back later.

Dan

maltbarley · Post by **maltbarley** » Thu Aug 28, 2008 5:57 pm

Well let me give you the scenario:

I'm fermenting in a conical inside a beverage fridge. The fermometer is stuck to the side of the conical about 12" from the top. The thermowell (and probe) are within 1" of the same height. My controller is set at 61* with a 1* swing. So, being rather warm in my garage, the fridge kicks in and cools the fermenter (said fridge has an aggressive constant circulation when on) to temp and then cycles off. Eventually, the heat soak finds its way to the center and kicks in the cooling but I think the fermometer is greatly influenced by the ambient temp.

bwarbiany · Post by **bwarbiany** » Thu Aug 28, 2008 7:21 pm

dhempy wrote:But another thought is to build a permanent set up like I did for my kegerator. Basically I took a 2 plastic jug, made a copper thermowell in the top, and set it in the bottom of the kegerator. 2 qt will change temps faster than kegs BUT is more stable than air so the freezer doesn't kick on/off as freqently. Now for fermenting, a thermowell in the vessel is best, but this provides another (cheap) option.

I wouldn't do this for fermenting. Because fermentation is throwing heat, the fermenter will be hotter than the liquid inside the plastic jug. It's better than simply leaving your temp probe out in ambient air, but not anywhere near as good as taping the probe to the side of the fermenter.

dhempy · Post by **dhempy** » Thu Aug 28, 2008 7:53 pm

dhempy wrote:Haven't paid attention .. luckily I've got a batch fermenting now in my ferm freezer ... it is likely past the main endothermic stage. I'll check and post back later.

Dan

I'm reading 51 on the Ranco and between 50 and 52 on the Fermentap on the side of the carboy. This is on the Vienna brewed last Saturday using a thermowell.

Dan

brew captain · Post by **brew captain** » Fri Aug 29, 2008 5:46 am

Add ice packs as needed...

You guys need help!

Cheers!

lars · Post by **lars** » Fri Aug 29, 2008 8:21 am

Brew Captain wrote:Add ice packs as needed...

You guys need help!

Oh, and foil, use lots and lots of foil. It is VERY important that you use FOIL.

Now where's my foil hat. I know those aliens are after my thoughts...