DIY Glycol Chiller build

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Mcbobs

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After a year of burning ice like crazy for recirculating ice water through my unitank's chilling coil, I decided it was finally time to look into a glycol solution for maintaining fermentation temps. Looking at all of the different commercial options and realizing that I really didn't want to spend $800-1000 for glycol, I decided a DIY approach was more my style.

Looking around online, there really wasn't much information on how to get a homebrewed glycol system going, but I was able to find just enough info to get things started. I learned a lot while building my system and thought sharing what I did might be beneficial to someone else looking to get a glycol chiller going.

For anyone else looking to add a diy glycol chiller to their equipment, hopefully my build journal will help you out!

https://ornatebrewingco.com/2020/01/12/my-diy-glycol-chiller/
 

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I know this thread is a bit old, but the responses on your site page were pretty recent. You document everything well, thank you for that! It looks like an amazing build!

I have been going through ice fast when I am doing a 5G fermentation (40-60# per), and I am adding two more 5G fermentors, so being able to maintain temps on all three at the same time is necessary. I don't want to go through that much ice (much less move the melt water), so glycol it is!

I am planning to build my glycol chiller in the next couple of weeks, just assembling the parts now. I have a cooler I have been using already, so I should be able to adapt it for an A/C unit (5K) and three separate cooling systems through the lid. I have the extra ink bird to run the A/C, so I think all I need now is the A/C unit, a recirculating pump for the glycol, and the glycol itself. I haven't decided if I want to box in the A/C as you did, or just let it hang out in the garage. With the filter screens in your box, does your A/C pick up a lot of dust? The glycol should be sealed inside the cooler and dust-free.

Am I missing anything?

On a related topic, do you worry about air ingress in the fermentor when you cold-crash? I can see this being the next step in my process, if it is an issue.
 
Are you making 15 gallon batches or 3 different 5 gallon batches at different stages of fermentation? If you're going to run three separate cooling circuits each will need its own pump and inkbird. Unless I'm missing something in which case I hope someone chimes in with a better solution.

My chiller lives in the basement and dust isn't an issue but an enclosure sure would make it look nice. Id rather just let it breathe.
Your cooling fluid should be sealed from from air to prevent evaporation and therefore dust free. I use water but that creates problems like rust and a drain and clean every couple months. I use my chiller for post boil chilling and fermentation temp control /crashing. Spills happen when moving pipes around and I'll just deal with the rust and cleaning as opposed to glycol cleanup. At a 34f cooler temp it does require a separate pump directed at the condenser to prevent ice build up.

You do have to worry about air ingress during cold crash. How you deal with that would be fermenter dependent. With my 60l spiedel fermenter I just give it a few pounds of co2 pressure and check every day with a squeeze. I have the parts for a gauge but haven't installed it yet.
 
I make 5G batches, but I also make cider, wine, and mead. So I am going to have one cooling control & pump for the A/C, and three independent, one for each fermenter. I am looking also at the draw each makes, no desire to flip a breaker when cooling three ferments at the same time.
 
Are you making 15 gallon batches or 3 different 5 gallon batches at different stages of fermentation? If you're going to run three separate cooling circuits each will need its own pump and inkbird. Unless I'm missing something in which case I hope someone chimes in with a better solution.

My chiller lives in the basement and dust isn't an issue but an enclosure sure would make it look nice. Id rather just let it breathe.
Your cooling fluid should be sealed from from air to prevent evaporation and therefore dust free. I use water but that creates problems like rust and a drain and clean every couple months. I use my chiller for post boil chilling and fermentation temp control /crashing. Spills happen when moving pipes around and I'll just deal with the rust and cleaning as opposed to glycol cleanup. At a 34f cooler temp it does require a separate pump directed at the condenser to prevent ice build up.

You do have to worry about air ingress during cold crash. How you deal with that would be fermenter dependent. With my 60l spiedel fermenter I just give it a few pounds of co2 pressure and check every day with a squeeze. I have the parts for a gauge but haven't installed it yet.
I'm just starting to read about these DIY glycol systems and don't know much about the specifics involved but I may have some input on the three pumps. While it might seem an opposite example, I rebuilt my hot water radiator heating system in my house from whole house to 4 separate zones. One way to do that was with 4 pumps, effectively making four smaller branches similar to the original. My original pump was still good and certainly large enough. Another way to make it work is to have the electric furnace deliver hot water to the pump and then split to four zone valves, each valve is linked to a separate thermostat. Hot water goes through the valve to the radiators in that zone and returns to the furnace. There is an intermediary part of the system, the zone valve controller, which receives the call for heat from all the thermostats and it tells the furnace to turn on and which zone valve(s) to open. There's also a check valve at the end of each zone to keep the water going one way. So the difference is each zone in my system has a zone valve not a separate pump. For heating, you probably still need a check valve on the zone end regardless. I don't know with a multiple pump system what is used to control the pumps and furnace, that is, what acts like the zone valve controller. There are if ciyrse variations to systems, I started with a functioning furnace and pump, but my furnace electronics are late 90's. I think in my case cost is somewhat of a wash initially but I think it's easier to replace a zone valve than a pump and a little cheaper on a unit basis.

Long answer but I think you could build three zones with potentially one pump. I didn't quite understand the condenser issue but potentially that could be an extra zone. As far as whether it would be cheaper to emulate my heating system, I'm not sure. The pumps you might use off the shelf might be cheaper than a zone valve.

What size tubing is commonly used for glycol systems? Shorter zone runs than a house too.
 
This is intriguing. I would need to check my local electric parts store to see about automated flow control valves, but then 1 pump and 3 flow control valves with three temp probes/controllers would work. Anyone ever do this before?
 
Not wanting to lead you down the wrong path I did a little searching because it was a couple of years ago that I rebuilt my heating system. The zoning that you are interested in is similar to a zoned hydronic heating system.

Mainly focus on the upper half, there are separate zone circulators controlled by the multi-zone relay center. That relay center receives information from the thermostats and then fires the boiler and in added complexity also works with the water heater for hot water in the plumbing system.
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vs using zone control valves. Zone control valves (number 3) and a zone controller @1 (green). The zone controller is basically a fancy switch that receives the thermostat information. Basically, you have multiple thermostats where any one may need to turn on the boiler/furnace. [Note, the water heater is not integral to these two diagrams but potentially could represent the glycol reservoir. My water heater is separate in my system so I am not sure about how that part works in these diagrams.] Pump is @2.
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If I read correctly, the OP's system uses a temperature controller to keep the glycol at 25F with a submersible pump and then a separate temperature controller on the fermenter which operates a fermenter pump. A boiler or furnace has what I think is called an aquastat that is equivalent to the temperature controller on the air conditioner and glycol pump.

Two well known companies for zone control valves are Honeywell and Taco. From what I saw, a zone control valve runs upwards of $65 in the heating world. I think they are generally 24V which is another function of the zone valve controller. There's probably other applications in industry for electronic control valves, but I think electrical supply house would send you to plumbing and heating supply. I like supplyhouse.com myself. The pumps one might use here are likely less than $65 but likely lacking a bit in quality. Certainly a plentitude of other options in the heating and cooling world. I'm not a heating or AC person, I just recognized the problem as similar to what I had encountered in my home heating rebuild.
 

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Here's how a guy by the name of Colorado Boy does it commercially with a single pump. In essence, it's done with a manifold loop, controllers and some valves. Overall it's really pretty simple.

 
The one issue about controlling it with a single pump is that you would have to leave the pump on all the time in the simplest design with the assumption that a pump needs to be on while the AC unit is on. You could repurpose the pump in the glycol reservoir to run the loop but it would need to stay on and not be temperature controlled. With the AC unit controlled by temperature, there will be times it is off but the pump would need to run in a single pump system when the fermenter needs cold.

A submersible pump costs about the same as a 110V solenoid valve. (That valve would need a plug for the temperature controller.) This is assuming there is a need for the AC pump, you would need two pumps and three valves for a 3 zone system or you would need four pumps for the 3 zone system. The difference is 3 valves vs 2 pumps.

In order to have the pump come on when cold is called from a fermenter, something like the zone valve controller would be needed for the zone valve system. The zone valve controllers run about $100, I think it has a 24V transformer, which appears to be more commonly used for the zone valves and solenoids, plus the thermostats are 24V. Something simpler would be a switch that when it receives a signal for on from any one of multiple sources, it turns on the device. That's what is built into the zone valve controller, potentially not a very complicated item but I don't know what it is. Kind of like a three way or four way switch but the logic is different.
 
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It's an "end switch" inside the zone valve controller that turns on the circulator. This is my controller for the heat. I'm not good with wiring schematics other than put the wires here, here, and here.
 
I am going to try to write this out to understand this better. Please correct me if I am wrong:

A. If the pump in the glycol's purpose is to keep the A/C unit from icing up, it only needs to run and circulate while the A/C is on (at least this is what I understood from other posts on the topic). So the Inkbird (or equivalent) would only turn the A/C+pump combo on when the glycol gets too warm. This system works independent from the pump(s) for the fermenter(s).

B. As for the pump system for the fermenter(s). Each fermenter has it's own temperature controller and thermometer. The options here appear to be:
1. have an individual pump for each fermenter that runs off of that fermenter's individual temperature system, or
2. have one pump that turns on when any of the temperature controllers turn it on-this also requires automatic on/off flow valves/solenoids for each fermenter that open/close at the command of the temperature controller for that fermenter, or
3. have one pump that always runs (like the youtube video above) and flow valves/solenoids that open/close and thereby redirect the flow of cold glycol to the appropriate space, as controlled by the individual temperature controllers. I believe this pump could also serve the purpose of keeping the glycol flowing and de-iced, thereby eliminating (A) above, but it would be running 24/7.

It would seem that:
#2 requires a level of electrical engineering/programming that I think is beyond me at this time.
#3 seems electrically wasteful (and stressful to the pump) unless there is a constant flow of fermenting beer, cold crashing, and/or lagering in the fermenter. This sounds easier than #2, but still requires a bit of engineering.
#1 seems the simplest and most cost-effective solution for my three 5-Gallon fermenters (or carboys, as the cooling system I use fits a bucket/conical or a standard glass carboy).

Rational or crazy?
 
It's an "end switch" inside the zone valve controller that turns on the circulator. This is my controller for the heat. I'm not good with wiring schematics other than put the wires here, here, and here.

This is fascinating and helpful. So instead of heating, it's cooling. And Taco makes all of the parts to accomplish the flow control and such?
 
I am going to try to write this out to understand this better. Please correct me if I am wrong:

A. If the pump in the glycol's purpose is to keep the A/C unit from icing up, it only needs to run and circulate while the A/C is on (at least this is what I understood from other posts on the topic). So the Inkbird (or equivalent) would only turn the A/C+pump combo on when the glycol gets too warm. This system works independent from the pump(s) for the fermenter(s).

B. As for the pump system for the fermenter(s). Each fermenter has it's own temperature controller and thermometer. The options here appear to be:
1. have an individual pump for each fermenter that runs off of that fermenter's individual temperature system, or
2. have one pump that turns on when any of the temperature controllers turn it on-this also requires automatic on/off flow valves/solenoids for each fermenter that open/close at the command of the temperature controller for that fermenter, or
3. have one pump that always runs (like the youtube video above) and flow valves/solenoids that open/close and thereby redirect the flow of cold glycol to the appropriate space, as controlled by the individual temperature controllers. I believe this pump could also serve the purpose of keeping the glycol flowing and de-iced, thereby eliminating (A) above, but it would be running 24/7.

It would seem that:
#2 requires a level of electrical engineering/programming that I think is beyond me at this time.
#3 seems electrically wasteful (and stressful to the pump) unless there is a constant flow of fermenting beer, cold crashing, and/or lagering in the fermenter. This sounds easier than #2, but still requires a bit of engineering.
#1 seems the simplest and most cost-effective solution for my three 5-Gallon fermenters (or carboys, as the cooling system I use fits a bucket/conical or a standard glass carboy).

Rational or crazy?
A. Yes.
1. Yes.
2. Yes.
3. Yes, you could configure the return port to flow post the AC coils much like a whirlpool port.

#2 It required some study on my part for me to figure out my heating system. It was challenging and ultimately saved me a lot of money in my house but it might not be worth the ~$20 for this application. Engaging for me because I could apply what I learned (and mostly forgot!)

#3 It's electrically wasteful but those pumps are made for aquariums and fountains so perhaps not a big deal mechanically but sure it would wear it down prematurely. Sometimes though it's the on/off that kills the product.

#1 I agree.

So the end switch isn't doing what I was thinking. It's just a delay that gives the the valve time to fully open then the pump activates. It seems that what the zone valve controller is doing is simply like having switches wired in parallel for a single light. Any switch turns it on but all switches have to be off to cut the power. DON'T ANYBODY DO THE FOLLOWING WITHOUT TALKING TO SOMEBODY ACTUALLY QUALIFIED LIKE A REAL ELECTRICIAN OR ELECTRICAL ENGINEER. I think it would be the same as having an extension cord with three male ends and one female end plugged into the the three temperature controllers while on the same branch circuit. The temperature controllers are switches.
 
This is fascinating and helpful. So instead of heating, it's cooling. And Taco makes all of the parts to accomplish the flow control and such?
I'm not sure if Taco manufactures pumps but they make the zone valves and the controller. My pump is a Bell and Gossett 100, it's kind of a standard workhorse. Thing I didn't quite recall though is that the thermostats are low voltage (24V) coming into the zone valve controller. But I was wondering if perhaps a different sensor would work like on my EHERMS. That feeds into a PID though and those are more expensive than the usual Inkbirds. Now here's a cheaper temperature controller that's very basic with no step functioning that would work on the AC unit. There's a similarly designed Inkbird but it didn't have the temp sensor with it.
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I wanted to thank you very much for all of the effort you have put into this thread, because I'm learning a ton.

Oh, and "Not Now, John." Excellent taste in music.

If you like ciders, sours, barley wine, or imperial stout; that's what I have in bottles. PM me an address, I would love to send you a box of "yeast samples."
 
Thought I should update someone else's thread, :rolleyes:.

I finished my build this past summer (2021). I have only been able to use it for 2 batches so far because of work, but here is what I have learned:

1. I probably should have a vertical cooler (~8-9G) instead of a horizontal cooler; more of the cooling vanes would be immersed and therefore, more efficient. I am running 7.5G in a 25-30 quart cooler, so about 25-30% of my vanes are not in solution.

2. The Anvil cooling systems don't have enough surface area to drop the temp in the fermenter below 45F. It doesn't matter what temp the glycol is, 45F is as low as it goes.

3. The A/C unit doesn't run any more often, it seems from casual observation, to keep the temp at 25F in the glycol vs. 40F. This may change when I add the other two fermenters into the mix (right now it is only cooling one). But they are doing ales/wines/meads/ciders at an average of 65F, so unless I am cold-crashing or dry-hopping, this shouldn't be too much load, even with three fermenters going.

4. It needs to be at 25-26F to bring the fermenter (6 1/2G) down to 45F for dry-hopping and cold-crashing and not running 24/7.

I have not tried to get the A/C to run cooler, as the Anvil cooling system is the limitation here. 45F is the best it can do, it just doesn't have enough surface area to drop a fermenter any lower. There is a lot of condensation on the hoses, but as I have wrapped them in insulation, it's not so drippy, and probably as efficient as it's going to get.

Cleaning the system is going to be a hassle, as I can't really use CIP balls with this setup (YET!), so I am moving a 5G bucket of solution over to the fermenter to dip the cooling coils into for a soak before a scrub. If find a good system for plugging the lines, I could disconnect the coils and soak/scrub it all away from the glycol system. Not sure what would be good to plug the hoses yet. Screws? Plastic caps? IDK, they don't have to hold pressure, just keep it from leaking.

Hope this helps others in their builds!

Peace!

Reevesie
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2. The Anvil cooling systems don't have enough surface area to drop the temp in the fermenter below 45F. It doesn't matter what temp the glycol is, 45F is as low as it goes.

FYI, I found a way to drop the temp even lower in my fermenter. I'm not sure how the cooling coils are oriented in your fermenter so this may not work for you. I have the SS Brewtech Conical and the glycol connections are high and low coming out of the side. For fermenting when temps stay above 40F I attach the inlet to the top connection. When I cold crash I move it to the bottom connection and I'm able to get 4F to 5F colder inside the fermenter. I've been able to get it is as low as 36F inside the fermenter.
 
Sounds like a great solution! The Anvil cooling system coils are thin and only do one up-down circuit inside the fermenter. One of the cool things about the SS Brewtech cooling coils is that they are a coil, so a lot more surface area for cooling. I went cheap on the coils because I couldn't go big, so I have the cooling limitation that others might not have.

I did just recently add a fermentation/lagering box to my setup, so I can either move the fermenter into the box for cold crashing (room for 1-2) or move it to a keg and then cold crash. The box holds three 5G kegs, so I am more inclined to cold crash in the keg and have more beers in the pipeline.

Learning all of these processes to make better beer is never-ending!
 
Awesome input! I have been thinking about doing the same with an old A/C. The price on a new chiller for home brew is very expensive.
I've also been floating the idea on using a zone off my heater to preheat my HLT since it is already hot. I will have to investigate further to see if this is a possibility.
 
Awesome input! I have been thinking about doing the same with an old A/C. The price on a new chiller for home brew is very expensive.
I've also been floating the idea on using a zone off my heater to preheat my HLT since it is already hot. I will have to investigate further to see if this is a possibility.
The zone addition has possibilities for sure. I'm having to work on my heat system as we speak. Zoning has led to a situation where my electric furnace is oversized. There are four 6000W elements in mine. It's kind of dumb in that they all turn on sequentially, and this is just too much for one zone. The furnace doesn't have much of a brain, just a high limit on the aquastat to turn it off and then a differential to turn it back on. I just installed an outdoor reset which I am told incorporates a PID controller. Unfortunately, my pump sprung a leak and I am waiting on a pump from NV so I can't say how well it works.

Anyway, on my furnace, the water is heated to 180F and if it exceeds that it turns off, the differential is 24 degrees, so it will drop to 156 and then refire if the call for heat is still there. Depending on your furnace and the temperature at which the water is maintained, a zone might be potentially added. Thinking of your suggestion, on my system, I could pipe a zone to say an immersion chiller to transfer heat. The zone control valve is ~$100. I have an electric brew rig, so I don't know if this would gain me anything except perhaps it could be quicker. I would be paying for the electricity both ways. I doubt I could actually transfer it quickly enough before the aquastat would shut it off. In my system, the furnace overshoots when heating my problem zone and that has two radiators that total roughly 10,000 BTUs. One I know because I bought it and one is an old radiator that is hard to guess. A smaller furnace might not have that problem. The surface area of an immersion chiller is probably smaller than a house radiator. It might short cycle though and that is what my issue is that I am trying to fix with the outdoor reset. Even if the furnace was not firing, you would need to get the circulator pump to stay on.

My system also works at 12 psi. So any sort of quick disconnect one should be extremely careful as the water would be very hot although potentially a QD may not be necessary.

Some hydronic systems also heat water for hot water but I don't know how that works as I have a separate water heater.

Very interesting idea I may keep it in mind!
 
Here's a thread (Anyone tried using forced hot water funance as heat source to HLT?) about your idea @mud1070 . I looked up what an indirect water heater is in relation to a furnace/boiler for a hydronic heat system. It operates like a zone where the hot water from the furnace enters a tank and heat is exchanged, looks typically like a coiled tubing design. The furnace usually has the potential to work with this separate zone as does my zone controller which would be wired slightly differently. You would think these indirect water heaters would be less than say an electric one but most are at least $1000. I'm wondering why I don't have one on my system as originally there was almost certainly a coal furnace in my basement. There's a chimney flue and no gas lines. Maybe oil though. My electric furnace is a beast 120,000 btus where a rough calculation for my house is south of 90,000 btus needed. My electric furnace is really old or else I would consider putting one in but I want to go to a heat pump. This would fix my small zone problem I'm almost certain.

In that thread someone mentions using a manual valve which you could do, also if going pex you would need the oxygen barrier pex tubing. If I were to add an exchanger zone like this, it might be an alternative to a 50 amp panel as I could use this to heat the HLT back up while continuing the boil with my rig's panel. Maybe an additional PID controller for the zone depending on how to fine tune it. I don't know if I really want to brew twice in a day. Recovery rates on those indirect water heaters are pretty good though suggesting this might heat the HLT up quickly as the HLT is about 1/3-1/4 in size than a typical water heater tank but brewer specific.

Sorry I know it's off topic but that other thread is almost 10 years old!
 
I was always ignoring the information about the domestic hot water (indirect water heater) in the diagrams I posted recently (post 7) but I get it now!
 
Funny but I ended up back at this thread as I was interested in Anvil's carboy coolers. Unfortunately, early December my electric furnace (electro-hydronic boilerer) bit the dust. It's basically a stack of four water heater elements surrounded by a cast iron rectangular block about the size of a small briefcase with a channel running through it for the water to heat up. I really wanted to go with a heat pump but I really wanted heat and I knew I could install a replacement boiler from the same company "readily and easily". The job was neither! I first attempted a repair of course, which failed due to a hairline crack in said cast iron block. Wishful thinking let me break it down completely and scrub it with a toothbrush and old bottle brush first. Followed by needing to run a neutral on the 240 line as the old boiler didn't have one (40 ft of #2 AWG), much like an old dryer line upgrade needing one for electric brewing. I got a "new" boiler for about 45% off-new in the box--part of the whole saga.

I had a continued interest to build a glycol chiller out of one of our window units but as I mentioned, no heat pump yet so still need those. I ended up getting great deals on two Brewbuilt X2s (no jackets) and the Icemaster 100 (Birthday and Christmas) so I am working on getting the chiller up and running. Individual pumps is the way I am going, still about $20 from Amazon vs. nearly twice that from the chiller companies, same gph. What's a bit costly are those valved quick disconnects for the glycol lines, from about $8 to a little over $20 for a male female set, two sets per fermenter! That and the various TC fittings and additional accessories not included on the unis. Oh well the maintenance guy needs to get paid once in a while! I was thinking though that I would either keep some carboys or get maybe get a Fermonster or Fermzilla. Hence my interest in the Anvil cooler and its abilities.
 
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