Fermentation temp control with glycol reservoir

[gregkeller]

Ok, so my brain started thinking today about some ideas for controlling fermentation temps. Here is what I'm thinking of. Please tell me if this would work or not.

I want to get two of the 15 gallon ace rotomolded conicals. Each would have a stainless coil in it attached to the screw on lid and would hang down into the fermenting beer. These coils would have insulated tubing that would be hooked up to an aquarium pump sitting in a 5 gallon bucket of glycol that is sitting on the hump of a 7 cubic foot chest freezer. This would be located in my basement and I'd want it to ferment down to lager temps sometimes but mainly ale temps. I live in nj, so basement temps range from 60 in the winter to 75 or so in the summer. I could insulate the conicals with reflextix or something. The pond pumps would be hooked up to an eBay temp controller (one pump per controller)

My biggest concern, and the deciding factor on this would be my ability to continue to use the rest of the freezer for its actual purpose. I don't want to take up the whole freezer with a glycol reservoir, and I don't want to put another freezer in my basement. So I just want to have a bucket of glycol in there. My concerns are that 4-5 gallons of glycol would not be enough volume to regulate 2 10 gallon batches of beer, especially if I was trying to lager something.

Any ideas?

 

[Hang Glider]

My experience is that it takes 5 gallons of glycol to keep my water-bath method under control. It holds 2 5-gallon carboys ...
At 3 gallons, it just couldn't reach equilibrium - the returning glycol heated up the reservoir more than the freezer was happy with, and it ran too often, while the fermenter could barely hold 70.

However, yours is an immersion system, so the translation is meager.

 

[Kuruts]

I just did something identical to what you are looking to do. I used 1/4 ss coil inside two 14g conicals. My first reservoir was 5 gallons, between the heat from the submersed pump and the returning glycol, it wasn't very efficient. I move to a kitchen garbage can from Lowes which held 14 gallons. This seems to be working much better.

I am also going to switch to a centrifugal pump from Harbor Freight ($40) so I do not create any pump heat in the glycol.

Lastly, 1/4 ss coil is extremely restrictive and my original pond pump (450 gph) would not create enough pressure to actually pump the glycol. Using a 1/6 HP submersible pump now, working well besides pump heat.

Let me know if I could help any more. The most cost effective and easiest thing for me on the temp control side was Ranco controllers from Pex supply.

Good Luck!