I recently stepped up my home brewing game, going form 2 gallon batches up to 5 gallon batches. This means it takes a lot longer to heat the wort to a boil, and even longer to chill the wort back down. My first 5 gallon batch took over 8 hours to cool down. Most people would simply use an ice bath, but my pot is too big, my sink is too small, and I didn’t think of using a large plastic tub or big bucket until I just wrote this. So, I decided to make my own copper wort chiller, or coiled heat exchanger.
- Spring Tube Bender
- Protein powder jug, bucket, or any cylindrical form
This is a pretty simple build, and the first step is to create the basic coil shape. If you look elsewhere online there are many different recommendations on how to do this. The most important thing to do is to prevent the copper tubing from kinking bending. Many people opt to use a spring tube bender to keep the tubing from having these issues, but I found that do be too tedious for the main coil portion. A more novel idea is to fill the copper tubing with water, and then freezing it. The ice then holds the inner diameter and allows you to bend the copper tubing. However, I was too eager and did not want to wait for water to freeze, so I just went for it. Luckily, copper tubing comes in a coil so all you have to do it stretch it out and each coil at a constant radius.
To do this you need some sort of form, I decided to use a protein powder jug from Costco. Carefully wrapped the coil around the form, and cinch it tight working from one end to the other. Make sure to leave enough excess on either end for your inlet and outlets.
Now that the main portion of the coil is made, the spring tube bender is useful. The inlet and outlets to to have sharp bends. This will keep where they meet the vinyl tubing outside of your boiling pot. This is important because you do not want any leaks at the joints to drip or spray into your wort and contaminate or dilute it. I recommend using some DW-40 or other lubricant between the copper tubing and spring tube bender. Simply push the spring over the tubing, and bend to the desired shape.
This creates a very nice shape, but copper is a very malleable metal so I needed a way to have my wort chiller keep it shape. My solution was to use some copper wire to tie key points together. I had some old solid core copper wire lying around my dad’s garage, so I cut some 3″ lengths and stripped them.
Finally, a way to get cooling water in and out of the wort chiller is needed. That is where the vinyl tubing comes it. It is important that is has an ID (inner diameter) equal to the OD (outer diameter) of the copper tubing so that it can easily fit over it. Slip the vinyl tubing over the copper tubing and then tighten down a hose clamp over the joint.
The final step is adding an attachment to connect the inlet to some sort of water source. This will most likely be a kitchen sink or garden hose. I currently do all my brewing in the kitchen, so I got an attachment that connects to the sink. Important note, make the inlet feed to the of the coil not the bottom. This will create better flow in the cooling wort and increase rate of heat transfer. The reason for this is the wort at the top of the pot will be hotter because it is less dense than the cooler wort that will sink the the bottom. Yay thermodynamics.
Currently, the outlet water flows to the planter below the kitchen, but to save more water another coil could be made and placed in a cooler. The two coils could then be connected with a pump between them to keep cycling the same cooling water through the system.