This is a very simple project for a homebrewer to tackle and a very useful piece of equipment to have around. A wort chiller is a device that speeds up the process of cooling your wort. The chiller is more convenient and faster than an ice bath and the quicker chilling aids in beer clarity while reducing the risk of contamination.
Who, what, why?
There are a few kinds of wort-chillers for the homebrewer. Plate Wort Chillers
are the most expensive, at around $200, but also the most efficient. Counter-Flow Wort Chillers
, in which hot wort enters at one end of a tube and cold water enters at the other end of a tube wrapped around that first tube, are a little more complex but also very efficient. Immersion chillers, which this article focuses on, are the least expensive and easiest to make.
The basic concept is cold water flowing through a coiled tube of highly conductive metal. That coiled tube is immersed in the hot wort. Because it has much more surface area in contact with the hot wort it cools the whole container down much more quickly than setting your brewpot down into some ice water. Of course this works much better in northern climes where the cold water temperature is significantly colder than it would be in the south.
I had two additional factors that made me want to make this chiller. The previous owner of the house left some coils of 3/8″ copper tubing, which makes the project significantly less expensive, and we currently have to boil our wort upstairs and then lug it down to the basement sink for an ice bath because our kitchen sink is too small. In any case the project should not cost more than 40-50$ (as opposed to 60-80$ to buy a new one) and you’ll be saving yourself the effort of lugging around bags of ice.
To start you’ll need 25′ or more of copper tubing. Copper because it’s such a conductive material. I used 3/8″ because I had it on hand but it also seems to be the most convenient. If you use a larger diameter pipe you’ll have to pass through a larger volume of water to keep it full and if you use smaller you need a longer pipe to get the same surface area in contact with the wort.
The copper will likely come in a flat coil. You now have to acquire something called a pipe bender. Luckily it’s not an expensive industrial one but just a simple tightly-coiled spring with one end flared. It keeps the soft copper from crimping. Find something a bit smaller than your brewpot and, using the pipe bender, mold it a bit at a time into a nice large spring. Take the bottom bit and bend it up and through the inside of the spring to meet up with the topmost bit. Now all you have to do is get two pieces of flexible hose with a 3/8″ inner diameter (in my case) and some small hose clamps and you’re 90% done.
The final bit is a connection to your cold water supply. In my case this was three separate bits that would help me get it to a faucet connection. I needed this because I have to do my brewing in the kitchen. If you’ve got a propane burner and you’re brewing outside or if you’re in your basement you may need just a couple of pieces to get to a hose connection. Basically it’s a 3/8″ barb fitting and let your hardware store person know what you need to hook it up to.
When you’ve got the whole thing constructed you’ll want to give it a little wash-up. To use the wort chiller simply immerse it in the wort for the last 15 minutes of the boil to sanitize it. Hook it up to your hose connection or faucet and let it run until your wort gets down to temp. Rinse and repeat with your next batch.
Cost from my locally-owned hardware store (big chains may be cheaper)
3.79: 3/8″ x 1/2″ barb MIP adapter (connects to hose)
4.99: Dual aerator to male hose (connects to faucet)
3.99: 1/2″ x 3/4″ FHT hose adapter (connects barb to aerator)
8.26: 3/8″ inner-diameter x 9/16″ outer-diameter vinyl tubing (14 ft @.59/foot)
3.58: Stainless steel band-ss screws (2 hose clamps @1.79 each)
3.29: 3/8″ outer-diameter spring tube bender
27.90 total cost not including copper
1. Keep in mind that I already had the copper tubing, which is about 23$ for 20′ at Lowe’s, and that I got way more vinyl tubing than I needed. You may be able to rummage around for some of the fittings and hose clamps as well. If you shop more wisely than I did your total cost may be around 45$, a pretty significant savings for a fun and easy project.
2. Remember to wash your chiller before using! One of the articles below suggests hot vinegar. And don’t forget to immerse it in the hot wort to sanitize during the last 15 minutes of the boil.
3. You may wish to keep it filled when not in use, to inhibit bacteria growth. If so you should get some stoppers for the ends.