Immersion chiller for fermenter?

[Sadu]

It's winter now so cooling isn't a pressing issue for me, but previously I was using a swamp cooler and I want something more automated. Fridge is not an option.

So I was thinking of adding a small copper immersion chiller to my fermenter, though I haven't seen anyone else do this?

The idea is that I drill 2 holes in the fermenter lid and stick a small 2 metre copper chiller into the fermenting beer near the top. A small 12v water pump pushes water through the chiller. The water also goes through a 12v peltier water-cooler block designed for computer CPUs. Or if that is too complicated, then just a chilli bin with ice bottles. All rigged up to a temperature controller so it's only cooling when needed. For heating, a heat belt, also connected to the temperature controller.

What I like about this is that the cooling is done at the top of the beer and the heating is done near the bottom so in theory there should be less hot/cold spots as the hot beer will move near the cooler and the cold beer near the heater. It's also very cheap ($20) and requires far less space than a fridge or fermenter closet, much less management than a swamp cooler.

I haven't seen anyone else do this so I thought I'd ask if this has come up before? I have all the parts here now so I'm going to run some tests before I go drilling up my fermenter. My biggest concern was whether the copper will taint the beer over time? Maybe stainless steel would be better?

 

[Bowtiebrewery]

Honestly, it will work in theory, but the cost of doing this and the potential introduction of bacteria would lead me back down the road of using a swamp cooler. It will work just as well.

The only other option I would suggest is a son of fermentation chamber.
http://www.ihomebrewsolutions.com.p.../wp-content/uploads/2012/10/chiller-plans.pdf

I built one early on and it was worth it.

 

[atoughram]

I dont think the peltier cooler has enough cooling capacity but I'm interested in your results!

 

[dsniegocki]

This is essentially what the SS BrewTech FTS system does for their brew buckets and chronicals... theirs is nothing more than a stainless coil attached to the lid, submerged in the fermenting beer. It uses a thermowell and a temperature controller that turns a 12V pump on and off, and they leave it to you to submerge the pump in an ice bath or something (I use a sealed corney with sanitizer/water that sits in my keezer). You can also set it to "heat" if desired and put the pump in a bucket with an aquarium heater, if the ambient air ever gets too cold.

For me, it works really well and I don't see why you making one would be any less effective. The coil in direct contact with the fermenting beer cools it very efficiently, and the commercial version also relies on the convection effect that you describe. I would recommend a stainless coil as it would be much easier to keep clean.

 

[Sadu]

Honestly, it will work in theory, but the cost of doing this and the potential introduction of bacteria would lead me back down the road of using a swamp cooler. It will work just as well.

The only other option I would suggest is a son of fermentation chamber.
http://www.ihomebrewsolutions.com.p.../wp-content/uploads/2012/10/chiller-plans.pdf

I built one early on and it was worth it.

Thanks for the feedback, and I have definitely been considering the son of fermentation chamber.

However for this idea, the cost is pretty minimal and full automation is a real advantage over a swamp cooler in a climate where temperatures swing a lot.

2m Copper coil $10
Peltier $1.25
Cooling block $3
Recycled CPU fan $1
Water pump $4
2x grommets $2
Recycled 12v power pack $1
Hoses (had these already)

The potential for bacteria comes from where the hose meets the copper, that connection needs to be tight. This risk can be mitigated by running starsan as the cooling solution so if a few drops get in the beer it won't get infected. Rubber grommets need to be sealed properly too. Copper coil can get a 15 min boil in between fermentations to sterilise so that shouldn't be a problem.

In terms of difficulty, I see this as much easier to build than a son of fermentation chamber, less materials needed, a lot less space. The peltier idea is experimental - I'm going to give it a try but if it doesn't work or isn't efficient then using a bin of ice as the coolant will be just as good. So without the peltier it's just a small water pump with 12v power supply, copper coil, hoses, growler full of starsan in an ice bin.

The downside is that it becomes much harder to move the fermenter around when it's connected to hoses, and removing the lid is going to be awkward. Cleaning is going to be a hassle also, one more thing to sanitise.

I'll post some pics on the weekend once I have this up and running, hopefully.

 

[zippybasher]

I plan on this exact setup and have almost everything to make it work. Except the coil. You need to use Stainless cause fermented beer and copper is a no no. Something about PH? Cant remember right now.


Problem for me was getting a SS Coil to fit inside my kettle fermenter (which is 14" Diameter!). I couldn't bend a SS tube in a small enough circle without actually putting a crease in the tubing. I need to revisit this as Summer is approaching, maybe a small tube bender? The 304 grade SS tubing is cheap enough to try again.

I ended up using the SS tubing for a chiller and that works great....

Also, I was going to do as mentioned above, put a corny with water in the keezer for cool water recirculation. Simple enough.

 

[TexasWine]

I'd recommend doing the calculations to figure out how many Peltier devices you're gonna need. I've seen some numbers batted around a long time ago, and if my memory serves me correctly, for a batch size of 5 to 6 gallons you'll need multiple.

Also, where are you going to put this contraption? A hot garage wouldn't be a good place. You probably know this, but Peltier devices work off a temperature differential. The warmer the room temp, the warmer the temp will be to which they can cool.

 

[Sadu]

You need to use Stainless cause fermented beer and copper is a no no. Something about PH? Cant remember right now.

This is the reason I posted this thread, rather than charging in and trying it out. Thanks for the feedback.

So I'll try to find a stainless coil to use.

In the meantime, I used the 2 meters of copper as a secondary wort chiller - used the water pump to recirculate iced water through this little chiller. My big wort chiller connected to the hose which is better for cooling high temps but not so great getting those last few degrees down to pitch temp. It worked really well - with the addition of this little chiller I managed to cool a 10G batch in the same time as a 6G batch.

 

[Sadu]

I'd recommend doing the calculations to figure out how many Peltier devices you're gonna need. I've seen some numbers batted around a long time ago, and if my memory serves me correctly, for a batch size of 5 to 6 gallons you'll need multiple.

Also, where are you going to put this contraption? A hot garage wouldn't be a good place. You probably know this, but Peltier devices work off a temperature differential. The warmer the room temp, the warmer the temp will be to which they can cool.

Thanks. I bought 2 peltiers since they were really cheap and I like electronics projects. They only need to cool a few degrees but if they can't do that then I can fall back to ice packs in a chilli bin swapped daily for the coolant supply.

This is going to run in my small portable office, which gets real cold at night and warm during the day. Right now it's winter so it's always cold. SWMBO won't let me keep fermenters in the house but also this way I can keep an eye on them during the day if temperatures do happen to spike.

 

[SleepyCreekBrews]

Don't put copper in your fermenter, the ph is too low, and will corrode the coil, leaving copper compounds in your beer.

 

[Sadu]

I just rigged everything up. The peltier is absolute rubbish, left it going for 5 hours, came home and it was 0.5c below ambient temperature. The peltier gets really cold if it's just cooling itself, but as soon as the water block is connected then it struggles.

To be fair I don't have any thermal grease between the peltier and water block, but I'm not sure that's the problem. Other people have warned that peltiers aren't up to the job, now I see what they mean.

The peltier and fan weren't expensive, I'm a few bucks out for the cooling block.

However the project can still go ahead just fine using a cooler bin with ice bottles as the coolant. Just waiting for a length of stainless tube to arrive on the courier, then some fun trying to bend that, then might be in action with this project.

In the meantime the 2m copper chiller with pump works pretty great for recirculating iced water through boiling wort, in conjunction with my existing copper chiller connected to the hose. Definitely not wasted money at all on that part.

 

[Xernex]

Any updates here? I just had the same exact thought.

 

[Sadu]

Yeah actually.

The 2m of stainless tube arrived. I bent it into a small immersion chiller. Much tougher and slower to do this than copper, but didn't need any special tools. I just used bottles/tubes of different sizes to form the shape without any harsh bends.

I have used the stainless chiller once to crash cool a batch prior to bottling. Didn't use temperature control for this, I just had the pump on for 4 days changing the ice in the cooler a couple of times. I don't know how low it got the beer temperature, but when I crash cool I aim for below anything 50f rather than proper fridge temps and that clears the beer out well.

It is wintertime for me and ambient is 10-15c, so not that hard to keep things cool at the moment. But I need to get my processes good for summer.

So the short term solution is to have the stainless coil inside each fermenter beer, using a chiller full of ice as the coolant, changed daily. For heating there is a heat belt wrapped around the base of the fermenter (needed since it still gets below ale temps at night). STC-1000 to control these.

Long term I will have a fridge with a bucket of coolant in it, which feeds the stainless coils in several fermenter. The advantage of this method is that I can independently cool 3+ fermenters from one small fridge, and the rest of the fridge can be used for storing yeast and lagering bottled beer. Unlike a dedicated fermentation fridge which is only good for fermenting 1-2 batches in at the same temperature.

I feel this is a pretty good process. For small batches I will put the coil plus an aquarium heater in a swamp cooler and this wiull do the same job as having a coil in the beer.

Will try to get some pics next time I use this, but I think it's going to be great for summer.

 

[Xernex]

Awesome thanks for that - I'm pretty sure my next step is building something like this for my fastferment and if it works well i may build a second for my other fermenters.

 

[DannyBoy408]

I did something very similar to this. https://www.homebrewtalk.com/showthread.php?t=583359
It works as expected. I got the idea from the same place, chiller on the ssbrewtech fermentors.
I use a cooler and change the ice out daily and it works great but it's not turn on and leave. It's worked great to keep fermenting wort around 70ish. The idea of a frige or aquarium cooler has come to mind as well. Let us know what route you take.

 

[Sadu]

Cool DannyBoy, that's pretty much what I had in mind originally. I would have thought if you had a temp controller it would be pretty much turn on and leave (apart from changing ice bottles)?

I ended up changing my plan to temperature control the swamp cooler water instead of putting the coil inside the fermenter. The main reason for this is that I brew 1/3/5 gallon batches and I can use the same process for all batch sizes.

I just posted pics of my build here...
https://www.homebrewtalk.com/showthread.php?t=590275&goto=newpost

 

[DannyBoy408]

I really want a set and forget it system. Meaning no ice or heat change. The controller does great switching but I need something to keep the water cool without my help. The problem is when the cold water gets hot the cold setting gets stuck on. I have a cold frige I can do what you suggested and stick a bucket in it and have hoses in and out to cool the water.

 

[DannyBoy408]

Just get a fridge. This GDM 10 cost me 250 on Craigslist and works awesome. Set it and forget it, sort of.

View attachment ImageUploadedByHome Brew1479183167.005267.jpg

 

[Sadu]

While a fridge is great, the issues I have are that you can't run 2 batches at different temperatures and the rest of the fridge is no good for storing bottled beer or kegs. So you really need a fermenting fridge and a serving fridge. Great if you have the space, not so much if you don't.

I'm pretty happy with my system of fermenting outside the fridge and using the fridge to cool the swamp cooler. It's set and forget for ales. Also set and forget for lagers in winter - in summer I can only do 1 gallon lager batches and even then I need to supplement with ice bottles a couple of times a day during the active stage.

 

[TexasWine]

While a fridge is great, the issues I have are that you can't run 2 batches at different temperatures and the rest of the fridge is no good for storing bottled beer or kegs. So you really need a fermenting fridge and a serving fridge.

There are ways around this. When I first started I only had a keezer whose temp was set at 35F. I would ferment in the keezer by strapping a heating pad to it followed by a sleeping bag to insulate it. Then I'd throw a towel on top for good measure.

The STC temp controller would turn the heating pad on/off to control the temp. The probe was simply taped to the fermenter under the insulation. Worked perfectly.

The rest of the freezer was used for storage. It would additionally hold 4 kegs and my yeast bank. And it's not even one of those monster freezers.