Temperature Control

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HopSong

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Just a question about controlling temperature during fermentation. Up till now, I have tried to maintain my temps by:

1. Putting my fermenter in a large water filled bucket that I put frozen water bottles in. I'm pretty successful at keeping the water at 62* even in the summer. I don't know the actual temp of the beer.

2. Fermentation chamber (freezer w/external control)(It's outside on my porch). I've kept the freezer at close to 62* during the day.. but at night the temps drop into the low to mid 50's.. and the internal temps drop to that by morning. I don't have a dual controller to provide some heat. And, as in case 1, I don't know the temps of my beer.

In case 1, I just use a floating thermometer to monitor the water temperature. In case 2, I have my temp probe in 1 qt mason jar filled with water.

This leads to my main question is.. is this sufficient.. or should I really pursue adding a thermowell to my fermenter.. will it be that much better? The problem I see is that the diameter of the Johnson control is pretty large and short of drilling another hole in my new Speidel fermenter, I don't think the stopper is large enough to be able to contain both the thermowell and the airlock.

I'd like to be able to do my initial fermentations at 60-62* wort temp for the first three or four days and then ramp up to about 68* till it's done. I know the yeast creates an exothermic reaction during the heavy stages of the process.. and therein lies my reason for the question.

Whew! This is getting long.. but, I don't know how to shorten it w/o my reasons being posted.
 
Without measuring the actual beer temp you won't know for certain what temp you have going on in there. But you should be able to estimate within a couple of degrees no problem. Personally, I wouldn't sweat it. At some point you will get a ferm chamber set up and be able to control your temps a lot closer, but I really don't see how 1-2 degrees difference over several hours is goign to hurt the beer.

As long as there is fermentation happening and your temps aren't too high you should be ok. You are already doing about all you can without some sort of automated system.
 
Can you move the fridge indoors, perhaps the garage where ambient temp doesn't drop below 60F?
Most controlers (not sure if yours is one) have an alarm output that can be used as a dual control mode. This is what I do actually, the main output controls the heatting, the alarm controls the cooling.
 
You should really get a few stick on fermometers for your vessel. In the case of the swamp cooler make sure to place it a coulple inches above the water level.

I have found that if I keep the water temp at say 62, at peak fermentation the stick on reads 63. I find that as long as you place the vessel in the tub, chill your wort slightly below desired pitch temp the wort equalizes with the water pretty well before active fermentation takes place and by then the temp rise is minimal.
 
Yah, I need to find a place in the house where SWMBO won't have a cow. I already have too much cr@p in here brewing related. :(

I think what I may wind up doing is to have a thermowell in the beer and have one of those cheap chinese electronic thermometers in it.. but actually doing the controlling from the probe being in the mason jar. That way, I won't have to worry about the thermal mass causing the freezer to get too cold. I think the freezer will be working real hard to get the beer down to 62*.. but once the freezer shuts off, the beer will continue to drop because the freezer is ice cold. What to do :) I'll get it figured out..
 
Try to move that freezer inside to avoid those big swings in temps. That will really affect your yeast during fermentation. One suggestion is to try to brew beers or use yeasts that thrive in the normal temps of where you live. It cuts down the styles you can brew but will allow you to have less stress during the fermentation.

If you dont have the room to move that freezer inside, how about putting some insulation around it so that you can try to shield it from those temp swings?
 
Seems like the cheap eBay aquarium controller would be the simple solution here. Then you could have heat and cooling in the freezer.
That's what I did since my basement was in the 50's also. It works great.
 
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