Home Made Wort Chiller

[sieglere]

Since wort chillers are expensive and can be as simple as a coiled viper pipe, does anyone have a compelling reason I shouldn't build one myself?

I have access to a machine shop and I estimate the materials won't cost more than $40 (the price is mostly copper and my labor is free). If there's one for sale under $40 with shipping, I don't mind the lazy route.

 

[jchudon]

Go ahead and build your own by all means!

The biggest issue is to make sure not to kink the copper tubing and from what I understand, it is very unlikely to happen to you!

 

[aryoung1980]

I built mine with 25ft of coiled copper tubing, a barbed garden hose thread, 3 hose clamps, and plastic hose. If you build it be sure to get braided hose otherwise it'll kink once the hot water begins flowing out. It's the easiest build ever so definitely make your own.

 

[gtmaus]

I built mine a few weeks back. 3/8" 25' copper from home depot and a couple fittings for about $30ish. It took less than an hour to make and works fantastic. My last batch, 6.5 gallon boil, cooled down to 68F in about 15-20 mins

 

[MMJfan]

I'm planning on making one and I was wondering how much quicker would a 50ft. wort chiller cool the wort vs. a 25ft. wort chiller?

 

[audger]

the difference isnt 50%, thats for sure. two 25 foot coils in parrallel would work better than 1 single 50 foot coil. the reson is because if the cooling water heats up to the temperature of the wort within the first 10 feet of coil, it doesnt matter how much longer it has to travel; it wont be picking up any more heat. two 25 foot coils just gives you twice the surface area.

 

[sieglere]

So as a mechanical engineer, this kind of stuff is really interesting to me.

So a wort chiller is basically a heat exchanger. With any heat eachanger, the efficinency (a technical term, but basically a synonym for effectiveness) is related to the length of the pipe, the material the pipe is made out of, the fluid flowing through on either side and the temperature difference. In the case of a wort chiller, copper's a great choice, you're not going to rig up some special cooling fluid, and the temperature of your faucet is mostly out of your control (unless you rig up an ice water prechiller). The only thing you can really change is the length.

The way the physics works is the heat energy exchanged is related to the temperature difference between the fluid in and the fluid outside the heat exchanger (a logarithmic relation to be overly spesific). So for example, the fluid in the copper will pick up the most energy right when it enters the hot wort, and when the wort is almost at the temperature of the water from your faucet, the heat exchanger will be picking up almost no additional energy. This being said, at the very end of the length of pipe, the water inside the copper is closest to the temperature of the wort and adding more length is less effective. You would see a drop in cooling time betweein 25 and 50 feet and even a drop still if you use 100 feet, but the drop will be small compared to the price of copper required to achieve it. A simple (well for those with a degree in engineering ) efficiency calculation will reveal the usefullness of adding one more unit of length to your heat exchanger, but a much more effective use of your pipe would be to construct a second heat exchanger and run it in the oppisite direction.

If you were to use all 50 feet of the pipe and made two heat exhangers with one nesting inside (leave enough room for your wort to flow freely) and ran them in oppisite directions, you could create a rudimentary counter flow heat exhanger. In a counter flow heat exchanger, the hottest liquid inside the heat exchanger comes in contact with the hottest fluid outside. With this being the case, it is possible to extract more energy out of your hot fluid and in our case, cool your wort faster. You also increase the flow rate of cool fluid through your wort, further decreasing the time to cool.

This setup would require two sources of water and that could be unfeasible, but it would be a better way to use your copper. It would also make you look fancy and you can use some engineering jargon to impress your happy chilled and soon to be alcoholic beer/friends

 

[dbrewski]

If you are doing 5 gallon batches, 25 ft should be fine. My old one was 25' of 3/8". I recently built a 50' 1/2" based off of Bobby M's build. If you go up in length, go up in tubing diameter, in my estimation it will be more efficient than just doubling your length of 3/8".

 

[bja]

So as a mechanical engineer, this kind of stuff is really interesting to me.

So a wort chiller is basically a heat exchanger. With any heat eachanger, the efficinency (a technical term, but basically a synonym for effectiveness) is related to the length of the pipe, the material the pipe is made out of, the fluid flowing through on either side and the temperature difference. In the case of a wort chiller, copper's a great choice, you're not going to rig up some special cooling fluid, and the temperature of your faucet is mostly out of your control (unless you rig up an ice water prechiller). The only thing you can really change is the length.

The way the physics works is the heat energy exchanged is related to the temperature difference between the fluid in and the fluid outside the heat exchanger (a logarithmic relation to be overly spesific). So for example, the fluid in the copper will pick up the most energy right when it enters the hot wort, and when the wort is almost at the temperature of the water from your faucet, the heat exchanger will be picking up almost no additional energy. This being said, at the very end of the length of pipe, the water inside the copper is closest to the temperature of the wort and adding more length is less effective. You would see a drop in cooling time betweein 25 and 50 feet and even a drop still if you use 100 feet, but the drop will be small compared to the price of copper required to achieve it. A simple (well for those with a degree in engineering ) efficiency calculation will reveal the usefullness of adding one more unit of length to your heat exchanger, but a much more effective use of your pipe would be to construct a second heat exchanger and run it in the oppisite direction.

If you were to use all 50 feet of the pipe and made two heat exhangers with one nesting inside (leave enough room for your wort to flow freely) and ran them in oppisite directions, you could create a rudimentary counter flow heat exhanger. In a counter flow heat exchanger, the hottest liquid inside the heat exchanger comes in contact with the hottest fluid outside. With this being the case, it is possible to extract more energy out of your hot fluid and in our case, cool your wort faster. You also increase the flow rate of cool fluid through your wort, further decreasing the time to cool.

This setup would require two sources of water and that could be unfeasible, but it would be a better way to use your copper. It would also make you look fancy and you can use some engineering jargon to impress your happy chilled and soon to be alcoholic beer/friends

That's pretty much what audger said in his post.

the difference isnt 50%, thats for sure. two 25 foot coils in parrallel would work better than 1 single 50 foot coil. the reson is because if the cooling water heats up to the temperature of the wort within the first 10 feet of coil, it doesnt matter how much longer it has to travel; it wont be picking up any more heat. two 25 foot coils just gives you twice the surface area.

And this was a lot easier to read.

 

[sieglere]

Fair enough

 

[lcf8088]

Fair enough

As a fellow mechanical engineer I enjoyed your answer.

 

[bja]

As a fellow mechanical engineer I enjoyed your answer.

As an Engineering Department Manager, I just thought it was a little excessive.

 

[bdjohns1]

A shell-and-tube would be the logical DIY extension of this. Get a couple feet of large-diameter PVC and a couple of end caps, then drill them to fit some small copper or stainless tube segments. Solvent-weld in some garden hose fittings to opposite ends of the PVC. Then, you just need to fab up something to consolidate the flow from the tubing at the product inlet and outlet. You could probably do something with a bunch of soft copper tubing and compression fittings to build a grid-like manifold on the ends.

Of course, at that point, all of the compression fittings are taking you close to the cost of a plate heat exchanger anyhow.

 

[gavball6]

the difference isnt 50%, thats for sure. two 25 foot coils in parrallel would work better than 1 single 50 foot coil. the reson is because if the cooling water heats up to the temperature of the wort within the first 10 feet of coil, it doesnt matter how much longer it has to travel; it wont be picking up any more heat. two 25 foot coils just gives you twice the surface area.

I double-barreled mine to maximize the 50ft of coil!

https://www.homebrewtalk.com/f51/my-diy-double-barrel-wort-chiller-317573/

 

[dbrewski]

I double-barreled mine to maximize the 50ft of coil!

https://www.homebrewtalk.com/f51/my-diy-double-barrel-wort-chiller-317573/

That thing is a trip! What is the best performance you've gotten with it?

 

[gavball6]

That thing is a trip! What is the best performance you've gotten with it?

I have only used it twice so far, but it has worked pretty well. Last time, it brought ~6 gallons down to 72 degrees in a little under 10 minutes.

 

[MMJfan]

Well, I had to go with a 50 footer because my choices at my local Lowes were 20 ft or 50 ft and they only that 3/8" ID in a 20 ft section so I went with a 50 ft section of 3/8" OD. And the cost for 20 ft of copper was almost $30 compared to $49 for the 50ft I got.

Still was cheaper overall than buying one at my LHBS.

I didn't bother double barrelling it to increase it's effectiveness as the main reason I made it was to not have to bother with ice baths and wasting money on ice.

EDIT: Boiled my wort chiller in a vinegar/water mix to clean it and decided to test it out after the boil to see how it worked. Cooled the water to 75 degrees in less than 10 minutes so I'm pretty damn happy with those results!

Here is a photo of my creation:

 

[ghack]

I've got two concentric spirals. works like a charm. The cooling will actually create a slight motion in the wort.

https://www.homebrewtalk.com/f51/new-immersion-chiller-103802/

 

[smokewater]

I wonder. What would be a more efficient use of 50 ft of copper, one 50 ft chiller or two 25 foot chillers connected in series with the first one sitting in an ice bath and the second in the wort.

 

[sieglere]

Why have a middle man? Just siphon from the ice bath. But in the hypothetical situation you posed, the 2 25 footers in series.

 

[MMJfan]

I wonder. What would be a more efficient use of 50 ft of copper, one 50 ft chiller or two 25 foot chillers connected in series with the first one sitting in an ice bath and the second in the wort.

The question would be, how much faster would the use of two 25 footers be and then there is the fact that you're still spending money on ice using the two 25 footers.

Seeing as how the 50 footer I made chilled my boil in less than 10 minutes, I'd say it wouldn't be worth your bother to make two 25 footers in combination with ice...

 

[sieglere]

It's times like this I wish my heat transfer book wasn't in storage. I could do a calculation for a cooling time for both.
The idea behind a second chiller in ice is inherently flawed because the idea behind it is to get the water colder before of goes into the primary chiller. If you wanted to do that, it would be easier to just start with the cold water in the first place (I.e. siphon it into the chiller).

Use the extra copper pipe as scrap or sell it for a few bucks. End of the day, you can buy some beer or ice with that extra money

 

[smokewater]

The question would be, how much faster would the use of two 25 footers be and then there is the fact that you're still spending money on ice using the two 25 footers.

Seeing as how the 50 footer I made chilled my boil in less than 10 minutes, I'd say it wouldn't be worth your bother to make two 25 footers in combination with ice...

I just wondered which would be more efficient. Ice will probably be necessary if you want to chill to lager temps or live in the south where ground water runs 80+. You will not chill lower than your water temp in the coil.

 

[MMJfan]

I just wondered which would be more efficient. Ice will probably be necessary if you want to chill to lager temps or live in the south where ground water runs 80+. You will not chill lower than your water temp in the coil.

True. I don't live in the south so I won't run into this problem...

 

[sieglere]

Funny you mention the water temp. I'm in Florida and our water is about 82 degrees. Took about 15 min or so to get it down to 100 and didn't want to go much lower. Ended up pitching my yeast a bit hot. The lock is bubbling away, so it worked out I suppose

 

[Near-Beer-Engineer]

This response is a bit late but I think this wort chiller calculator that I created can answer just about every technical question that was asked on this thread (i.e. how much better would it be to be have colder water, longer tubes, etc).

Check out this thread and click on the link to download if you'd like to give it a try:

https://www.homebrewtalk.com/f11/immersion-wort-chiller-calculator-376707/#post4720602