Water Fermentation Chiller

kenc_zymurgy said:

I think you will need to experiment. The reason I say close to the output tube is consider this:

Say you have 5 gallons of chill water in the fermentor cooler and you want to maintain 60F. It takes some time for a thermostat to respond. If the pump moves 1 gallon of water (just one minute for a 60 GPH pump) before the thermostat shuts it down, you have a mix of one gallon of, say, 40F water and 4 gallons of 60F water - that averages out to 5 gallons of 56F. That might be a bit more swing than you want.

Again, it will take some experimentation, but I'd lean towards a short cycle to avoid over-shoot, and move from there as needed. With a compressor, you want to avoid short cycles, but I think this will actually be best with just a pump.





That's what I think also. Also, calculate how much water the IC holds. From my comments above, you may find that all you need to do is pump the contents of the IC over to the fermentor. After that, the water in the IC has some time to sit in the ice bath and give its heat up. You might not really need to transfer any heat as it is being pumped.




Please do report back. Let us know some things like the controller settings, volume of chill water in the fermentor, in the ice bath, the volume in the IC, and your pump capacity (it would be good to measure how long it takes to fill a gallon jug with it hooked up - to see how it handles the restriction of the IC and hoses). It really helps us to hear how the theories really work out in practice. I do think this will work well for you.

-kenc

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Thanks for the comments. I have created a new thread here: https://www.homebrewtalk.com/f163/using-ic-mlt-fermentation-water-chiller-253770/

I will try to summarize my results here but for all details please refer to my thread above. This way people who do a search for this type of stuff in the future will find what they need.

From checking on the temps overnight, it hasnt overshot much (I currently have the probe on the opposite side of the pump). Held pretty steady around 62-63 F, until the ice melted sometime early this morning and the pump was running and only adding heat. I need to work on insulation so I can leave this alone for longer than once or twice a day.

Here's my ebay temp controller settings:
F1=17.0 C (set temp)
F2=0.5 (temp differential)
F3=1 (min. time in minutes that the controller stays 'off')
F4=0 (temperature calibration)

Guys and gals, thought I'd write my first post as a thank you for all the ideas here. I've got a room in the house that does pretty stable at 69F all day all year, but I've been wanting to really hit that temperature control for lower temp brews like Kolsch, etc. Using these posts I made my own lagerator, and so far it works like a charm.

The setup is a 1.7cu ft dorm fridge with a 5 gallon water bag inside set at around 36F. The rest is essentially the same: in the bag I've got a 60 GPH pond pump along with return line coming from the keg buckets. I stacked 2 of the buckets and filled the gap between them with big gap foam insulation (took 2 cans, mostly from the big space at the bottom). The return drain comes out the side (just a snug fit in a drilled hole along with some silicone), and is attached on the inside at the required water level (yeah, duct tape). The line from the pump squirts into the bucket above the water level. The pump is hooked to a Ranco controller and the probe is in a ziplok bag taped to the inside of the bucket halfway up the water level.





This is the first run, so I don't have a lot of data yet. I filled the bag in the fridge as full as it would go (probably 4+ gallons) and had it as cold as it would go overnight. The next day I put about 2 gallons of water in the bucket and added a couple dozen ice cubes to get the temperature down in the bucket to about 50. I brewed a half batch of Kolsch and put the fermenter in there, and voila the 2 water levels matched. I taped the return tube in the bucket at that water level, and set the Ranco at 62. It rose to 64 fairly quickly, the Ranco flipped on, cold water in, return water drained, and came back down in a minute or so. Even in an 80 degree garage, after settling the wort temp down, the temp holds for about 45 mins before triggering the pump. The styrofoam liner around the gap between buckets probably helps, pretty cool air in there.

No idea if it can hold a temp for lagers, but given it's apparent efficiency, if the water in the fridge is cold enough and the beer temp stabilizes, no reason it can't. We'll see.

So thanks again everyone for your input, now I can make non-estery beers!

Pete

I am very much a fan of this thread. We don't have a lot of square footage in the house, so everything has to go out in the unfinished garage. I've been keeping my current fermenting brew warm in a simple bucket with a 20 dollar aquarium heater. A few years ago I built a Son of Fermentation Chiller, which is good for holding a single carboy.

I'd love to make on of these for anytime I needed to be fermenting two at a time. Someone in here had suggested exchanging water with some kind of reservoir tank inside a fridge (where water would presumably be kept around 40 or so), but I'd like to keep everything on the ground. Would I need two pumps — one to pull water from the fridge, the other to pull water from bucket? Has anyone put it together in this fashion?

With summer almost here I thought I'd bump this thread. This could be very helpful for those of us that battle the heat to make great beer.

Couldn't you just build an insulated box to store your carboy. Then use a coil system with a compresser that utilizes pressurization and release of a gas to act as a heat sink for the air in the insulated box? You could probably rig up some kind of system so that when you open the door to the box, a little light comes on...

Norselord said:

Couldn't you just build an insulated box to store your carboy. Then use a coil system with a compresser that utilizes pressurization and release of a gas to act as a heat sink for the air in the insulated box? You could probably rig up some kind of system so that when you open the door to the box, a little light comes on...

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What a novel idea. I think I would call mine a refrigerator or freezer depending on how cold it gets.

Glad I found this thread. This was an idea in my head as I was pondering how to control my fermentation in my garage, while keeping it portable. My twist is that I have a large 3 day ice chest sitting around the house, and built a small keezer already. With the extra space in the keezer, where i can't fit a fourth corny keg, will be filled is a water source. I'm thinking 3 liter bottles that I could put in series. Hook up my march pump to the bottles. The march pump will push cold water into the ice chest though a immersion chiller, which is laying in a layer of water in the ice chest. The chiller will cool the water, and pump right back into the keezer (cold water source). The other option is that i have two immersion chillers that will be in series that will directly in the wort. Overall, the pump will be controlled by a johnson controller, and probe attached to the furthest fermentation vessel. Considering that it will be a closed system, there will not be an issue maintaining a prime on the pump. The only issues that i see is overall volume of water needing to move in order to cool the wort down, and over cooling the first fermentation vessel if I chose to do the series of immersion chillers. I have everything needed except the the immersion chillers (35 each) and a second johnson controller(~$80)

I have been doing something like this for my 15 gallon conical. I have a stainless tubing coil attached to the lid. I pump ice water through it from a cooler sitting on the floor. I use an STC-1000 controller which cycles the pump off and on.

Funblock: - way cool!

Dirty_Dog_Brewing said:

Glad I found this thread. This was an idea in my head as I was pondering how to control my fermentation in my garage, while keeping it portable. ....The only issues that i see is overall volume of water needing to move in order to cool the wort down, and over cooling the first fermentation vessel if I chose to do the series of immersion chillers. I have everything needed except the the immersion chillers (35 each) and a second johnson controller(~$80)

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Dirty Dog Brewing:

I did something very similar to this.

a few suggestions -
1) I found the minimum volume of water to achieve 65F in the summer in my garage was 5 gallons. More might be better, but less would not work for me.

2) a pond/fountain pump (cheapo) just sitting in the ice chest full time to circulate the "bath water" will remove the worry about the first vessel being colder than the others.

3) I used a transmission oil cooler (new) instead of an immersion chiller, so it's still a closed system - the fins collect the heat nicely. And my immersion chiller is not sitting in my fermentation vessel, should I choose to make another batch.

You have a transmission cooler sitting in the fermenter?

This idea is great, I will be doing this to regulate my ferments on my limited space/money budget.

I built a water fermentation chiller modeled closely on the OP's. The only significant difference is that I built lids (made of multiple layers of 3/4" foam insulation from Lowes) for my ice chest and the cooler that the carboy sits in. I'm glad I made the lids, they have definitely helped with efficiency of the system and limits the possibility of any foreign objects getting into the chill water. I also have a small (60 watt I think?) Aquarium heater plugged in to the heat outlet on my stc 1000).

Understand this system may not be for everyone, but for me it is perfect. I don't see myself moving to a fridge or any other temp control solution, for the following reasons:

1. Consistency. My stc 1000 temp probe is simply stuck in the chiller water...not taped to the carboy or anything. I have compared my actual wort temp in the center of the wort to my stc 1000 reading multiple times at various points in the fermentation process, and have never found more than 1.5F difference in the two temps.

2. Portability/space. I have nowhere to put an extra refrigerator (at least not anywhere SWMBO would allow) The water ferm chiller goes on my back porch during fermentation, and then gets broken down and put in storage when not in use.

3. Less sensitive to power outage. I live in rural NC, and our power goes out relatively frequently. Even in hot weather, the wort temp isn't going to climb much even if the pump doesn't have a chance to run for a couple hours. Worst case, I can always manually add cold water directly to the round cooler.

Hope this is helpful to some who are considering going this route.