My son is the beer maker but I make all of his equipment. Whenever possible I use discarded items that I can convert. At present I have his fermenting compartment side by side to his converted freezer that we use to store the cold kegs. I simply pump cold air as needed from the freezer to the fermenter to regulate the temperature.
I recently go ahold of a hot/cold water dispenser. I had planned on pumping the coolant from the hot or cold side as needed through a set of coils that I would place in the container of fermenting beer. My son seems to feel that contamination would be an issue and prefers that I just use a heater core with a fan and maintain the air temperature of the fermenting box.
Does anyone have any suggestions on how I could best use this cooler to control the fermenting temperature? I will probably use food grade glycol as a coolant.
That was my thoughts, I thought it might look a little cooler also to have the 5 gal bottles wrapped with insulated jackets instead of hidden in a box.
Anything that touches the beer (wort, actually, until the yeast get busy and the alcohol content rises) brings the potential of infection and can create off flavors or completely ruin a beer. This is why you son is reluctant for an immersed heat exchange coil. While it would be the most efficient way to cool it, IMHO it would not be worth the risk.
Again, IMHO - Keep it external unless you are also building a fermenter that has coils attached to the outside, so that nothing need be placed inside where the yeasties are working their magic.
I wonder if I were to build a plexiglass “box” filled with coolant that I could set the fermenting beer in. The coils would be in the plexiglass liquid filled box? He likes to bring his beer making buddies over to check out his operation so the visuals have some importance.
The fermenting beer is in the coils, and gets moved through a box that is full of chilled coolant?
Seems like a bad idea. I’ve only dabbled in beer-making, but you typically want to keep your fermenting beer still. With all that movement, it’d be hard for the yeast to really “dig in” and do their job.
No, the fermenting beer is in a 5 gal bottle. The coils are sealed and will have thier own glycol coolant running through them. I am just tring to figure the best way to transfer the heat from the fermenting beer back to the coolant running through the coils.
I’m not sure you can leave copper coils in contact with wort, since pH drops during fermentation, which can dissolve some of the copper in your product.
If you go some sort of plastic, one of the common sources of infection is having a glass or plastic fermentation vessel that has microscratches that will hold a biofilm, protecting microorganisms from whatever sanitization method you use. It would be hard to ever be sure it was really clean.
Right now I am using an old freezer that I extended the top on and added spickets for the beer. I am pumping the cold air out of here into the insulated fermentation box. It works well just not as pleasing to the eye as I would like.
If the air outside the carboy is enough higher than your ideal brewing temperature that you need to cool the carboy off, immersing a long, thin coil of coolant into the carboy is going to cool off the center of the carboy really well and the outer area not so much, so you’ll be creating a gradient of temperatures, probably ranging from “too high” at the carboy and “too low” wherever the coolant first enters the wort. Never startle your wort; it has very few ways of reacting and they’re generally not too tasty.
It really is going to be better for the beer if you find a way to keep the air outside the carboy at the temperature you want (65-75 for Belgian ales, 55-70 for most other ales, 40-55 for lagers). The usual way for homebrewers is to have the aforementioned spare fridge with a temperature controller hooked up to its power supply so it only gets electricity when the temperature goes too high (unless the temperature on its warmest setting is cold enough for your purposes, then you’re good to go).
I have heard of an industrious homebrewer who built another box the size of the fridge in front of it, so the refrigerator coils were having to cool twice the volume of air; as a result, it was warmer inside and he had enough room for two carboys. This raised the temperature on the warmest setting to high enough to ferment beer in, so he could have two batches going at once. The box was plywood lined with styrofoam, or the foam insulation you see getting nailed to the outside of new houses (Tyvek?). That might also work with your freezer, but then your freezer is going to be running 24/7.
I could see using a coil to chill wort after it’s been boiled. Seems like overkill for controlling the temps in a fermenter unless you are doing some very specialized brews.
That said, I’m not sure your son fully appreciates what he has HoneyBadgerDC. If you want to come over to my house and build some systems for cooling beer, I would never say no.