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homemade glycol system

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  • homemade glycol system

    I am planning to install a multiple tap system in my bar and do not have room at the bar for a larger kegorator. I was planning to route the beerline through a closet and into my garage where I would set up a full size fridge (with a top freezer) for my kegs. My run will be close to 20' with several tight bends. Most people on this site say air cooling does not work well at those longer lengths and with several bends. I think I need glycol cooling.

    I thought I could purchase a full size fridge with a freezer on top. I would place a tub with a fountain pump in the freezer and use that to cool my beer lines. I could use the freezer thermostat to keep my coolant at 29F, then use the refrigerator thermostat to keep my beer at 38F.

    1. will this be an effective way to cool? what issues may I have? How large of a container of coolant should I have?
    2. are the standard fridge controls good enough to regulate the beer temp or do I need to purchase a Jonson type controller?
    3. I noticed glycol towers tend to be a bit more pricey. What are the issues with simply routing my cooling lines up into an air cooled tower?

  • #2

    I have 30'ft and I setup a pretty good air-cooled system. I didn't have your bends. I have read (perhaps here someplace) that each 45 bend is like adding 5ft.

    I have since upgraded to Glycol......

    I used a 4" PVC for my return air, inside that I ran a 2" which ran the cool air into the tower and within that my beer line. The 4" was sealed to the bottom of the bar while the 2" went 1/2 way up the tower. This way as the cold air fell it was drawn back through the 4".

    All was going fairly well - My foam was well managed but the first draw from the tower was not so cold so I ended up dumping the first 3/4 of a pint if I had not been using the tower in the past 24hrs.

    The turn for the worse came this summer. I don't have A/C (I am in Canada and its not needed) and we were in a bit of a heat wave. This is when I noticed my tower had a fair bit of condensation on it. I went to check the temp of the freezer and the side of the beast was hot (very hot to the touch). Escentially what was happening is that my tower was acting as a heat exchanger and the freezer couldn't keep up.

    The Glycol system:
    I have a fountain pump and a 5gal bucket that is pumping glycol to the tower and then circulating back to the bucket.
    - Here are my learnings:
    Water has better heat transfer properties than Glycol so only add enough glycol that your fluid doesn't freeze. I initally filled my bucket with straight no-mix glycol. You can get this (cheap) at any RV place as they use it for winterizing motorhomes. I have since drained more than 80% and replaced it with water.
    - You need a big enough reseivor so that by the time you pump the fluid back to the tower the warm stuff has had a chance to cool down again.

    I am using a chest freezer for everything. Works well. I have since learned that a Glycol Engine (used in professional settings) is a small freezer that keeps the glycol signficantly cooler than what the beer is stored at. This allows the line to remain at the same temp as what the beer is stored at. In your case using the fridge for the beer and the freezer for the glycol is a brilliant idea.

    I hope I don't get crucified for the next statement but I "think" a tower that is designed for glycol actually has couplings on the bottom for glycol lines and these run close to the stainless beer shanks in the tower.

    My tower had no such fittings so I simply wiretied the glycol lines up the beer shanks and used a metal u fitting on the two glycol lines right over the spot where the shank goes into the tap. I then wrapped everything in tinfoil to increase the conduction between the lines.

    Finally with my freezer which was supposed to have a range from +5 to -25 (this is celcuis) 0 = 32 was not accurate at all. I ended up getting one of the miromatic controlers (brewers choice) and it now controls my freezer.

    Good luck with your project, good questions, you won't be sorry.
    " ... I'm fortunate to have a chemical engineering background, and one of the things I enjoy most is converting beer, wine, scotch, etc into urine...."


    • #3
      Thanks for the advice. You have answered many of my questions and have provided some good tips I intend to follow.

      It sounds like glycol is a requirement to do this or at least a more robust method.
      It also sounds like I should plan to have several galloons in my freezer, I suppose I might be able to get a way with less the cooler it is (as long as I do not freeze my lines and keep my %glycol at min)

      I will plan to buy and wire in a replacement controller for the beer compartment. I have read that temp variations screw with the pressure and flow.

      It also sounds like I might be able to get creative with my cooling lines and save a couple $$ with an air cooled tower. Some come both ways and I was wondering if they put something special in there. It sounds like if they do, it may not be necessary, if I DIY some added insulation and tie the cooling line to the individual beer lines in the tower.

      You are correct the glycol towers I have seen simply have connections at the bottom. I suspect it is simply for commercial applications to save time and having to customize the tower. Some towers I noticed only come in glycol, they look like they simply do not have much space for air flow.

      Thanks for the advice.

      Anyone have a similar system?



      • #4
        make sure you find something that will allow the freezer to get that warm. Most freezers will not allow you to set them that warm (29F). Mine at home has a digital controller built in and has an upper threshold of 8F.
        Our beer, which commeth in barrels, hallowed be thy drink
        Thy will be drunk, I will be drunk, at home as it is in the tavern

        Home Brew IPA


        • #5
          More good experience. Thanks.

          Looks like I will have to remove both the thermostat for the fridge and the freezer and replace them both with a Johnson, ranco or brewers edge type of controller. There goes the warrantee on the fridge!

          Any recommendations on controllers? Control, ease of wiring for this application ect.?



          • #6
            If you get the Micromatic one you don't need to do modify anything.

            You simply put the fridge/freezer or whatever your using for a cooler on its max settting. The Micromatic plugs into the wall - and then the cooler plugs into the controller. The controller simply cuts the power. A temp prope sits inside of your cooler and monitors the temp.

            Dead easy and no warranty violations.

            Of course I cut mine directy into the compressor so thats another story.
            " ... I'm fortunate to have a chemical engineering background, and one of the things I enjoy most is converting beer, wine, scotch, etc into urine...."


            • #7
              I have completed my conversion and am ready to buy my first keg for this system. I have read many posts and tried to piece together as many best practices as I could. It is a remote 3-tap “t” tower that I converted to glycol, I made my own trunk lines, converted the top freezer to pump and control my coolant at 29F and the bottom fridge for up to 3 kegs at 36F.

              The reason I did not go with air cooling is that although I have a closet behind my bar, it is actually the space under a staircase. I did not want a chest freezer, since there would be too much lifting in a confined area and I likely would break things restocking after a few beers. I wanted a vertical fridge that is easy to get at, easy to load, with plenty of room to more easily maintain.

              What I did will void your warrantee. (This is not the exact order, the order is purely to help convey the method):

              I will spare you my testing, planning and investigation details and fast forward to the conversion. My budget was $1400, which was the cost of a good two tap self contained unit that can hold 4 corny kegs with all the supplies (tanks, taps, etc.) I ended up around $1200, but still would like to buy some odds and ends. Big ticket items – $415 for fridge (Menards), $321 for air cooled tower with 3 Perlick 525 SS’s, two Ranco ETC’s at $55 each.


              • #8
                I am working now to figure out how to post pictures.


                • #9
                  Freezer conversion:
                  Most low end refrigerators have a single temp controller, to my disappointment. The way they (mine) was designed to work was to control the fridge by cooling the freezer and using a knob adjusted damper to diver air to the lower box until it is at the desired temp an let the freezer be less controlled. I decided to reverse that with the two Ranco’s. They are digital and seem to be much nicer and more precise than the Johnson. They measure temp directly and have set back amounts, very nice for the same price as a Johnson. I bought them from a heating and AC place online, not a beer store. Much cheaper.

                  Then I noticed where and how the cool air enters from the freezer (from the damper control) and glued some lexan over the fridge cooling vent (more on why later). I also noticed during my testing that this fridge has a timer that automatically defrosts after 10 hours of run time, it shuts off for 30 mins to defrost the coils. There is a drain next to the fridge cooling vent, I needed to be careful not to cover that thing up or the cooling unit in the freezer would not drain while it was defrosting.

                  You can see here the drain pan and the fitting that goes to the tube in the back of the fridge, this is how my fridge drains - down to the floor for to a drainage pan by the compressor.

                  let's see if the photo's attatch for me.
                  Attached Files


                  • #10
                    Then I ran external power up the freezer control (mounted to the outside of the fridge). Using a wiring diagram for my fridge I got at the manufactures’ website, I located the temp control wires. They were located in the assembly at the top of the lower box. I noted that the fridge is cycled on/off simply by making contact of the two wires. Utilizing both the wiring diagram of the fridge and the Ranco, I now had the Fridge temp control replaced by the Ranco to control my freezer only. I then ran the probe to the freezer and fastened things to the outside.

                    I added a junction box to the side to make all terminations to incoming power chord to both temp. controls, water pump and new fans (stay tuned). I also mounted two switches there one for the water pump and one for the rest of my add-ons. So I can run the fridge with or with out the water pump. A nice to have that also helped during testing.
                    Attached Files


                    • #11
                      Now the fridge:

                      The controller on the left is for the fridge. My plan was to simply use that to drive computer fans through two holes in the floor of the freezer, one fan blowing out and one blowing in. A word of caution, when drilling into your fridge, be careful to unplug it. I ended up cutting through some wires and had to repair them with some moisture proof epoxy.

                      But with my fridge diagram, some silicone, and some Great Stuff foam, I was back on my way.

                      I attached the two fans to some ABS fittings, I sized them to the ID of the ABS – 2” – 60x60x30 mm fans @ 10.2 CFM each. I used a 2” hole saw, so I had a good fit and used some silicone. I wired them to the fridge controller. When the temp drops, the fans kick in and draw cool are from the much colder freezer.

                      I then made some blocks to put my glycol tank on (a plastic tub) to keep it over my fans and make sure I got as much heat transfer to the bottom of the reservoir as possible.

                      I wired my cooling pump, to be located in the pan. I used 20’ of copper 3/8” od copper coil on my return line to help with heat transfer on the way back (it did not work with just the pan, I added 10 feet of copper, it still did not cool as fast as I wanted. I wanted it to be close to the freezer temp by the time it returned). The freezer fan blows directly on the coil return line. I also did not want the coil in the reservoir, since that may warm the return line slightly. I drilled holes in the top of the freezer and dropped bolts through to hang the copper coil.
                      Attached Files


                      • #12
                        I then made trunk lines with three ¼ inch ID beer lines, vinyl, ½ o.d. I wrapped them with aluminum tape, then with vinyl tape (I found that the window flashing tape at my home improvement store worked very well at a good price and was 4” wide). I then wrapped them with water line foam insulation and wrapped the bundle with black Duck tape. My trunk line was large, so to get the larger ID, I used more than one piece. I used 3/4” thick foam. I actually ran my lines first then began the taping and insulation process to make sure my lengths were good. My tower came with several feet of 3/16 beer line, I left that in place as that seemed to be the recommendation from what I read.

                        I ran them through my closet and out to the garage, about 20' of beer line.

                        I modified my tower with copper cooling lines – 3/8 ID and used cable ties to hold the beer lines in contact. I also ordered cooling blocks that attached to my facet shanks, and ran the copper through that with some sweat fittings. Then I put some gasketing on the top of my tower to prevent air flow and condensation.

                        Sealed off the beer lines, coolant lines, electrical connections and start thing up. Using water my coolant is maintained at 24 F and the water pours out of my faucet at 32-33F (recently bumped it up to 34 to keep the water from freezing.)

                        I just installed my first keg beer at 36F
                        Attached Files


                        • #13
                          more pictures
                          Attached Files


                          • #14
                            Nice design. A couple of pointers. Be careful with too cold of a circulation as this can promote beer stone bulid up - particularly in vinyl. This is the calcium oxilate that is from the beer. Chill haze.

                            Next, with all the work you put into your design, you fell short at the tower. Bridge the vinyl line between your cold blocks and copper with the foil tape and then insulate with your expanding foam.

                            What type water pump did you utilize?
                            Scott Zuhse, Instructor Micro Matic Dispense Institute


                            • #15
                              What I tried to do was to be sure my system has enough capacity to cool. I think I have achieved that. I am now adjusting the temps upwards on my freezer to determine the best set point to reduce the duty cycle of the freezer. I do not know much about beer stone, thanks for the pointer.

                              can you elaborate on the tower modifications? I do not quite understand the method you describe.

                              the water pump I am using is a fountain pump from a home improvement store with about 8' of head pressure.

                              I was concerned about expanding foam in my tower since it can get between the hose and the copper and then expand and cause separation. should I not worry about that?