Counter-flow Wort Chiller Plans

Posted to Homebrew Digest #1907, 12/12/95
by Harlan Bauer (

I just built one and I am extremely pleased with the results. Here's what I did:

1. ~45 feet 3/8-in copper tubing
2. ~45 feet 3/4-in I.D. commercial/contractor hose
3. modified/homemade Phil Phittings(tm)

The first thing I would suggest is to either buy outright the Phil Phittings, or at least go to a shop and look real carefully at them to see how they work. They are very well made, and are a whole lot easier than re-inventing the wheel like I did. If you make your own, you might want to increase the size somewhat (to accomodate the larger hose size) and replace the compression fitting that holds the tubing with a sweat on (I'll explain this later). So, here's how I made mine:

    -----------------------------------\     (2)
                                        \------------\  (3)
 (1)     3/4-in                             1/2-in                3/8-in
    -------------|           |---------/
                 |           |
                 |  3/4-in   |
                 |           |

1. This is where the hose is attached. You will need to extend this so there is room for a hose clamp and to make this section stronger, so sweat on a short piece of 3/4-in copper pipe. Over this I added a copper coupling with the stops filed out to thicken the metal and to make a tighter fit with the hose. IOW, the extension is double thick, the coupling slips over the copper pipe and butts up against the copper tee.

2. The tee reduces here. The tee I used was a 3/4-in x 1/2-in reducing tee. To this I added a short piece of 1/2-in copper pipe and a 1/2-in to 3/8-in reducer with the stops filed out so the chiller tubing will be able to pass completely thru.

3. Since the stops have been filed out, the 3/8-in chiller tubing passes all the way thru and is solderd in place. I did this to avoid a compression fitting here. I hate compression fittings, they invariably leak. Besides, if you do a good job, it looks REAL nice. You get extra points for neatness :-)

4. This is the other 3/4-in leg. To this I added a 3/4-in to 1/2-in reducer, a short piece of 1/2-in copper pipe and a brass male hose fitting. If you look hard for them, there is such an animal. It's simply a 1/2-in sweat-on with male hose threads.

That's pretty much it, and of course, you'll have to make two of them.

Now, once these are made, uncoil the hose in the back yard, cut the fittings off both ends and feed the copper thru. The straighter the hose, the easier this will be. Be sure to leave plenty of copper tubing sticking out both ends (more on this later). I them coiled this around a budwizer keg by rolling the keg over the hose. Try to keep it very neat, and have the hose lay on the keg in a single thickness like wire on a spool. Do not remove the keg.

Now it gets kinda tricky. I made some wooden "clamps" out of 1 x 2 pine that look like this:

         |-----------|----------------------|----------| Note that this is
         |   wood    |   Hose goes here     |   wood   | sitting side-ways,
         |-----------|----------------------|----------| in use, it will form
         |---------------------------------------------| a vertical leg.

Make 4 or 5 of these, but do it in such a way that the hose ALWAYS slopes downwards around the spiral. IOW, the short pieces of wood will be different sizes.

Carefully remove the hose from the keg and place these clamps on the spiral one at a time to hold it together. I used sheet-rock screws into the small pieces of wood. You might want to pre-drill to avoid splitting the wood. Be prepared to do a lot of swearing getting the first two legs in place, and some extra hands would be a god-send. The chiller should now be fairly rigid, and stand on it's own legs. Across the tops of two opposite legs, drill a 1-in hole and insert a dowel for a handle, just like a tool-tote.

Now you can solder on one of the copper fittings. The second one needs to be soldered on in such a way that the finished in-let and out-let will work with your set-up. On mine, I aligned the two male hose fittings perpendicular to the ground. You might want to configure yours differently.

Now, remember the 3/8-in tubing that I said to keep long? I had you do this so you can customize to your particular set-up. You could cut them fairly short and attatch braided hose to them, which is what I did; or you could use flare fittings, which is what I'm going to change to.

I attach the wort-out to a pump (this is to avoid HSA) and voila!

One final note: There is no reason that the chiller NEEDS to be a spiral like this. One could, for example set it up as a very long pipe if your boiling kettle and fermenters were in different rooms. Just be sure it will drain. This might be particularly nice if you brew on an upper floor and ferment in the basement.

Please feel free to e-mail me if any of this doesn't make sense, and I'll post corrections later.