Dual Stage Fermentation Temp Control?

Rudeboy · 05-11-2009, 06:29 PM

I listen to The Brewing Network quite a bit and JZ is always on about how important specific fermentation temp control is.

Then last month they were giving a Dual Stage Temp system from MoreBeer.

As I understand it, it is a digital controller with two outputs, a temperature probe and a termawrap. You wrap the carboy with the thremawrap and put the whole thing in a fridge. Then plug the fridge and the termawrap into the outputs. And set the digital controller. It turns on the termawrap to heat it up or the fridge to cool it down. And apparently you can keep the wort/beer’s actual temperature to within about a 1 degree F range.

So my questions are. Is that how it works? I’ve never seen one and am just trying to figure it out from the MoreBeer descriptions.

Does anyone have a similar system? How well does it work? How much difference does it make in the finished product?

My Ale fermentation system right now is a basement bathroom. Which is actually pretty good, in that I live in Northern Alberta, so the downstairs bathroom is pretty consistently at 15 C or 60 F.? Then with a little digital space heater and the door closed I can get up to around 25 C or 77 F and all points in between. But that’s just ambient temp and I’m not sure what the temp swing is. But I thought the thermal mass of the 5 gallons should smooth that out.

Still with JZ preaching about how important exact actual liquid temps are I’ve been toying with the idea of setting up this system.

Any thoughts?

Rudeboy

**conpewter** · 05-11-2009, 06:43 PM

I really do think it can take your beer to the next step to have temp control. I have a freezer set up in my basement. The temp control probe is taped to the carboy with some bubble wrap over it for insulation, this gives me a pretty close reading of the liquid temp. I then have the freezer turn on when it needs to cool down teh carboy. For heat during the winter I'll throw an electric heating pad in the freezer and turn that on. It heats it up till it gets too hot then the freezer cools it down. I know this wastes a bit of electricity but the heater is on the lowest setting and I don't want to buy a dual stage temp control.

Edit: usually I don't need the heat pad, basement stays 60-65 which is fine for most of my ale yeast.

Boerderij_Kabouter · 05-11-2009, 06:47 PM

I use a dual stage LOVE, a fridge, and a small space heater in the fridge to maintain my temps. I use a thermowell in the carboy to measure actual beer temp.

The link in my sig to the side-by-side conversion details my chamber

FlyGuy · 05-11-2009, 07:25 PM

I have a temperature controller and have used that with a fridge for fermentation control. Works very well, although it isn't always easy to get your fermentation temps dialed right in within one degree.

IF your basement is already cool (say 15 degrees C or lower -- note this is a BIG requirement), there is a much easier (and cheaper!) method that I greatly prefer. Get yourself a big Rubbermaid tub ($7) and a 50W or 100W aquarium heater ($15-25). Fill the Rubbermaid about 3/4 full with water and use the aquarium heater to get the water to the temperature you want. It will keep the water temp very stable, and the control is very precise (since many fish can't tolerate big temperature swings). Get this set up and equilibrated to the temperature you desire a couple/few days before you brew.

There are two big advantages of this approach, IMO:

1. You have very precise temperature control with the water bath, and it is dead easy to do things like start on the cool side for the fermentation then gradually ramp up the temperature towards the end (say for a Belgian strong ale that you really want to attenuate out).

2. The water bath absorbs all the temperature fluctuations, either from the heater or from the heat generated by fermentation. One issue with a fridge is that if you have a fast and violent fermentation, often the fermenting beer is many degrees above the ambient air temperature inside the fridge (the beer is generating more heat than it is losing to the air). In a water bath, this doesn't happen because the water bath absorbs a lot of that heat. This keeps your fermentation temps much more constant and really makes a big difference in the finished beer.

Note that obviously this method works well for ales, but won't help for lagers.