Wort Chiller Plans & Hints
The Counterflow Variety
The first piece of equipment that I built for brewing was a counterflow wort chiller. Although there are quite a few plans for constructing chillers at the Brewery web site, I found the illustrations in ASCII to be rather difficult to read. Furthermore, I was having trouble imagining how one could put all the pieces together. So, If you have been thinking of constructing a counterflow chiller, I think that you might find some help here.
Chiller design can take one of two basic forms: counterflow or immersion. Both designs have their drawbacks and advantages, and I will leave it up to you to decide. Personally, I chose to make a counterflow design, as this fit my brewing needs. Conceptually each chiller design uses heat exchange principles to rapidly cool boiling wort down to yeast pitching temperature. I won't get into why this is considered a "Good Thing" but rather focus on the construction of the chiller.
Permission to use the illustrations and photos for non-commercial use, as long as the Author is credited. Cheers!
A counterflow chiller is simply a copper pipe inserted into a larger diameter hose. Hot boiling wort is siphoned through the copper pipe, and cold water is circulated through the larger diameter hose in the opposite way the wort is flowing (hence the name,"counterflow"). The larger diameter hose in effect is a cooling jacket for the copper wort tube. The chiller has fittings ( or "end caps") to allow the ends of the copper tube to protrude from the hose while sealing the hose. The chiller is usually coiled up for convenience sake, but is not necessary. Does all this sound confusing? That's the biggest problem that I had as well. I'm just a simple kind of guy... Anyway, I found out that it's not so hard to understand after all. Please see the accompanying picture for a representation of what the chiller is and how its put together.
The following table outlines the basic materials you will need for constructing the chiller:
Tools Needed for the Project:
Let me tell you straight off, I am a crummy plumber at best (you don't even want to know about it when I'm at my worst...). If you are in the same boat, then you are in luck! If I could get this thing put together than surely anyone can. Plan out an afternoon or a couple of evenings and have some fun messing around with tools and fire (insert Tim Allen Grunts here).
Step 1: Making the End Fittings
(a) Get your work area ready, like your basement or garage or what have you
(b) A hole needs to be drilled in the end of the copper end cap. Before you attempt this, put your safety glasses on! Start the hole by using a hammer and nail. Use your power drill to enlarge the hole so that the flexible copper tubing will barely pass through it. Take your time on this step!
(c) Take your section of 1/2" copper pipe and use your pipe cutter to cut 3, 2" long sections of pipe. Take your emery cloth and smooth off the cut edges. The 2" pipes will be fitted into the three outlets in the copper tees, and the end cap will be fitted on the end of one of the pipe sections. Remember: the flexible copper tube will pass straight through this fitting, so position the drilled end cap accordingly.
(d) Sweat on the copper pipe sections to the tee using the solder and your propane torch. Don't forget to use flux on the joints! Sweat on the drilled end cap in the same manner. The accompanying photo above will give you an idea of how the fitting should look like assembled and soldered. If you are a better plumber than I, yours should look neater! Repeat the above to make a second end fitting.
Step 2: Making the Chilling Coils
(a) Uncoil the garden hose so you can work with it. The garden hose needs to be cut into a continuous section about two feet shorter than the flexible copper tubing. Plan to cut the hose in such a way that you end up with two sections about 12 feet long left over, as these can be used for your cooling water supply and exhaust.
(b) Carefully uncoil the flexible copper tubing, avoiding kinks. Lay the cut garden hose flat on the ground, and squirt in a little dishwashing liquid and water. This will make the next part easier... Working with a partner, slowly feed the flexible copper tube through the garden hose. This is a bit of a pain, but with the lubrication from the dishsoap and some help from a partner, it will go smoothly. Make sure that about 9 to 12" of copper tube protrude from the ends of the cut garden hose. You can always trim the garden hose back a bit if you were off in your measurements (like me).
(c) This is when the thing begins to look like a coil... Using some kind of a cylindrical form (I used a large tin that used to have snacks in it), carefully roll up the hose with the tubing inside it. Again, this works better if you have a partner to help. The copper is flexible, but it also holds it's shape fairly well. The idea is to create a neat set of coils. When you are finished rolling it up, use your zip ties or large twist ties (like the ones your hose came packaged with) and harness the thing together. This will keep the coils neat and tidy. If you are doing this outside, your neighbors are probably wondering what the hell you are making! (Grin)
Step 3: Installing Fittings and Supply Hoses
(a) Slide a hose clamp on each free end of the chiller. You don't need to tighten them at this point, just make sure they don't fall off. If you forget to put the clamps on before you install the fittings, you will be cursing.
(b) Push the copper tubing through the drilled end cap in the fitting. Slide the fitting down the copper tube, and push the garden hose up over the 1/2" copper pipe part of the fitting. (Do this for both ends).
(c) Next is the most tricky part of the whole project. You must create a seal between the drilled end cap and the protruding copper tubing. Do this using the propane torch, solder and flux. Take your time here, because if you don't take care it will leak and you will have to do it again (like me).
(d) Once all the parts have cooled down, fasten down the hose clamps tightly. If you forgot to put them on, you will have to remove the fittings and try again (ugh). Install the cooling water supply hose buy forcing one of the spare pieces of hose over the remaining outlet on the copper tee and clamp it tightly. Use the end of the hose with the correct coupling to attach to your faucet. Affix the other piece of hose with a clamp to the remaining fitting. Voila! You have just made a counterflow wort chiller!
Using the Chiller
Before you need to depend on your chiller, you better test it out for leaks. Hook up the cooling water supply hose to the faucet and run the water through it. Pay close attention for leaks at all joints, especially where the copper tubing exits the drilled end caps. Make sure that no water drips from the hoses where you have used hose clamps. If anything leaks, you may need to make better soldering joints or tighten up hose clamps.
After you have tested the unit for leaks, you should prepare it for use. Syphon some distilled vinegar through the wort tube to clean it. If you don't, the acidic wort will pick up all the oxides from the inside of the tube and deposit it in your beer. Syphon some rinse water through the coils a few times to remove any trace of the vinegar. Before you use the chiller for brewing, it is very important to sanitize the inside coils. This is one of the drawbacks of the counterflow design, as you can't see how clean or dirty the inside of the tubing is. Syphon sanitizing fluid through the coils a number of times, or use boiling water, and then rinse as normal. I cap the ends with some sanitized aluminum foil until I am ready to use the chiller.
Okay, now that your chiller is prepared and sanitized, it's time to use it! Connect the cooling water supply hose to the faucet, and make sure that the exhaust hose is secured in the sink, or better yet in your washing machine. Attach some sanitized racking hose from the wort-out side of the chiller and direct it to your carboy of fermenting bucket. Attach the wort-in side with some sanitized racking hose to your hop-straining device in the boiling kettle. (You must keep the hops and trub out of the chiller!) Turn the cold water faucet on, and begin to syphon the wort through the chiller. If the cold water supply to your house is very cold, you won't need to run the tap water full blast. With some fiddling, you can get exactly the temperature that you need. After you are finished, it is a good idea to thoroughly clean the wort chiller before storage.
Enjoy your new chiller, and brew up a storm. Cheers!
Page Text and Images © 1997-2001 Andrew J. Roberts