Water Fermentation Chiller - Page 13

**kpr121** · 06-28-2011, 01:44 PM

Quote:

Originally Posted by kenc_zymurgy

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

Thanks for the comments. I have created a new thread here: http://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)

PoppinCaps · 09-13-2011, 09:44 PM

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