DIY Super Cheap Counterflow Chiller Build

[jason.loxton]

I just finished building a counterflow chiller, and happy with the results, so figured that I would post here. Note: I am not anywhere near as handy as many on these forums, so you can inevitably improve on this.

I couldn't find cheap hot water-rated hose anywhere (50' is $54 plus tax at Home Depot), so I decided to see if I could use pex pipe. A few people seem to have tried this with mixed results on other forums. I picked up 20' of 3/4" pipe for $12.95 at Canadian tire. I already had 50' of 3/8" copper tubing, so I cut out a length of that. I placed a ball of tape on the end of the tubing to allow it to slide in easier, and added a little dish washing detergent as lube (I don't know that this was nec.). The tubing slid in with no real effort. I then coiled it around a corny keg. The pex coil had no problem doing this, and I could have gone a little tighter if I had tried. I then inserted 3/4" Ts into both ends ($1.99 at Canadian Tire), running the copper tubing out as in other builds. Since I didn't want to mess around with soldering, I cut two 1.5" lengths each of the thick silicone hose that was purchased in the Brewhardware group order (I don't know its diameter) and 3/8" ID siphon hose. I slid the siphon hose over the pipe and part way into the T (making sure not to extend it far enough to interfere with the flow of water through the vertical part of the T). I then slid the silicone hose over the outside of the T, as well as over the remainder of the siphon hose extending out of the T. This created a double layer of hose between the copper tubing and the clamp, ensuring a tighter seal then if I had just tried to use the silicone hose by itself. I used pex crimp rings to tighten around the two ends of the T, as well as just after the T to stop water from flowing out around the copper tubing. In my trial run, I used silicone hose for the water in/out, but eventually I am just going to cut up an old garbage garden hose for this, and secure it with a hose clamp. It seems to me that any garden hose will suffice since: 1) the water flowing out will be hot, but well below boiling, and 2) even if it breaks down under the heat, it is as easy to replace (with another garbage hose) as undoing a hose clamp. If people have extra of the silicone hose around, it worked perfectly though.

I just ran a test... The results:

1) No leaks. All the crimps held up just fine.

2) Flow rate is pretty good. Under just gravity, dropping from my stove to a carboy (a drop of about 2 feet) it had a flow rate of about 2 litres a minute, with my valve fully open (with the ingoing and outgoing wort running through 3/8" ID siphon hose for the trial).

3) It chills pretty well: At full flow rates (tap water temp of 59 F), it dropped the temp down to about 70 F. With the valve half closed (which affected flow rate, but not dramatically--I didn't quantify how much it did), temp dropped to about 66-68 F (reasonable ale pitching temps). It could hit 63 F or below by cutting flow way back (I want 64 F, as I often use Safale-O4 at cool temps, as a sub for American Ale yeasts), but this wouldn't be very practical. (I will probably just take 66 F, and then cool in my freezer for a short while before pitching.)

In short: Pex works really well, and if you already have access to some copper tubing (i.e., an old immersion chiller), you can build a counterflow chiller for about $20. Note: It would help if you had access to a crimping tool, as hose clamps probably wouldn't hold the pex tight enough. (Home Hardware let me use theirs in the store, but I live in a tiny town where people do that sort of thing.) This was mostly just a proof on concept for me this time. I used 20' of pex because that was the only length less than 100' I could get my hands on at a reasonable price. In Halifax, where you can buy by the foot, I imagine, inexpensively, I would definitely go for 30' of pex pipe. This should improve the chilling, without dramatically increasing cost or slowing flow rate.

[mr x]

Very nice.

[jason.loxton]

Note: The crimping band on the copper tubing wasn't quite the right size, and didn't really slide all the way up to the point where the two hoses overlapped. It still didn't leak, so perhaps the double hose thing is unnecessary. (If you were just using a hose clamp, I think I would still do the two overlapping layers of hose to ensure a tighter seal.)

[Jimmy]

Looks good

[RubberToe]

Well done! The silicone should hold provided you don't restrict the water output.

Sent from the brew timer.

[OldMalt]

I was thinking of trying to make a CFC and was considering how to do it on the cheap. I was thinking PEX pipe, since I'll be buying a large roll for the garden, but wasn't sure it would work as well. Glad to see your success, it has inspired me to go ahead with mine. Bonus: materials are on sale at Rona's store closing sale in Bayer's lake.

[akr71]

Bonus: materials are on sale at Rona's store closing sale in Bayer's lake.

When are they closing? The wife's idiot cousin gave us a Rona gift card at xmas - which means driving to Shediac or Halifax to use it and burning the $25 the card is worth just to get there.

[LiverDance]

They close in april

[akr71]

[jason.loxton]

As an aside, the silicone hose ended up leaking (more from how I had it clamped, I think, than a fundamental problem with the material: I punctured it). I ended up just grabbing two 1/2" threaded hose barbs I had, grinding off the threads so that they fit snug within the copper pex T, and soldering them in place. (The internal copper tubing is almost exactly the right diameter to fit flush within the hose barb. I filed it down to a very slight taper, and then just put a dab of solder on to keep it in place, and it is a nice compact solution. The Brewhardware silicone hoses fit right on for wort transfer, without clamps.)

[derek]

The wife's idiot cousin gave us a Rona gift card at xmas - which means driving to Shediac or Halifax to use it and burning the $25 the card is worth just to get there.

My mother sent me LCBO gift cards...

[akr71]

The wife's idiot cousin gave us a Rona gift card at xmas - which means driving to Shediac or Halifax to use it and burning the $25 the card is worth just to get there.

My mother sent me LCBO gift cards...

trade ya (since I'm visiting my folks this summer)

[derek]

My mother sent me LCBO gift cards...

trade ya (since I'm visiting my folks this summer)

Sorry, I went back to Ontario at Christmas, and they miraculously disappeared (I'm sure I wasn't to blame - it was the ~30 year old nephew & niece).

[Araxi]

That's pretty cool, well done.