Stainless Steel Wort Chiller?

I saw that one of the larger suppliers online has a stainless wort chiller for sale. It is cheaper than the copper ones that they sell. I know that copper is a good metal for exchanging the heat, but would stainless work as well?

Maybe I should have done a search first!! Sorry for reposting the question!!

Yes it will work, no it's not going to exchange heat as well as copper.

I believe that every foot of stainless steel conducts as well as every inch of copper. Sure, they are pretty but they are pretty worthless. IMHO.

Forrest

Austinhomebrew said:

I believe that every foot of stainless steel conducts as well as every inch of copper. Sure, they are pretty but they are pretty worthless. IMHO.

Forrest

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Have you tried one yourself Forrest? Perhaps not, since you don't carry them.

I bring 5.25 gallons of wort from boiling to pitching temps in about 20 minutes with mine. My old copper one is hanging from the garage rafters, getting darker and greener with every passing day.

I say its worth a look. I wanted to make one but i couldn't find the right tubing at the hardware store. Metal conducts heat well, plain and simple. Copper does do a better job but lets face it, our immersion chillers aren't the most efficient pieces of equipment nor are they extremely sophisticated. Most copper tubing is used in refrigeration. Thats where efficiency matters. We're chilling wort, a couple extra minutes is going to kill us. Or the wort, or the yeast. haha. =)

Austinhomebrew said:

I believe that every foot of stainless steel conducts as well as every inch of copper. Sure, they are pretty but they are pretty worthless. IMHO. Forrest

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You must have never tried one.

The thermal conductivity of stainless is in fact many times lower than that of copper.

However, in an immersion chiller, the rate of heat transfer through the very thin sidewalls of the tubing is insignificant compared to the rate at which the water actually absorbs the heat. If the tubing had much thicker walls, then yeah, it might be a problem, but as thin as they are I think it's fairly irrelevant.

irunxcjm said:

I saw that one of the larger suppliers online has a stainless wort chiller for sale. It is cheaper than the copper ones that they sell. I know that copper is a good metal for exchanging the heat, but would stainless work as well?

Maybe I should have done a search first!! Sorry for reposting the question!!

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Where did you see it, if you don't mind passing on the info.

Midwest carries them.
http://www.midwestsupplies.com/products/ProdByCat.aspx?Cat=231

BlindLemonLars said:

Have you tried one yourself Forrest? Perhaps not, since you don't carry them.

I bring 5.25 gallons of wort from boiling to pitching temps in about 20 minutes with mine. My old copper one is hanging from the garage rafters, getting darker and greener with every passing day.

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Stainless should have to be thinner than copper. It is a stronger metal when at the same thickness (more dense). It would not exchange as well as the copper at the same thickness. Since it can be a thinner tube and retain some strength, it may work close to copper. With the prices of copper up so high, stainless tubing may well make more in-roads.

I would like to see the results of a test. Forrest may be able to get ahold of one for free to test if he called the manufacturer and told them he wanted to test them to see if he should start carrying them.

Hoosierbrewer said:

Since it can be a thinner tube and retain some strength, it may work close to copper.

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That's really the key. I don't know how thick the walls of mine are, but judging by the weight, the tubing is very thin.

I've done no scientific tests, but having used it for my last half-dozen batches, I can state that it works very well.

Even if the walls of the SS tube were as thick as the copper (which they are not) the thermal conductivity of the metal is not going to be nearly as large a factor as length of tube and making sure you stir your wort while cooling. If your tubing had 1/4" walls then you might see a difference, but they don't.

your forgetting atleast with stainless you dont have to worry about oxidation of the copper. Even if it conducts heat a bit less efficiently than copper does it wont turn green. Isnt that worth it?

It all boils down to the thermal conductivity coefficient 'k'

k for stainless steel 16 W/m*k

k for Copper 401 W/m*k

http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html

copper is roughly 25 times more thermally conductive. Meaning that one would have to use about 25 times more stainless than copper to get the same effect.

And in regards to oxidation stainless steel is stainless due to a layer of chromium oxide on the outside. Copper on the other had takes quite some time to oxidize and due to the acidic nature of wort any oxidation that may have formed will be cleaned off.

b33rm3 said:

It all boils down to the thermal conductivity coefficient 'k'

k for stainless steel 16 W/m*k

k for Copper 401 W/m*k

http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html

copper is roughly 25 times more thermally conductive. Meaning that one would have to use about 25 times more stainless than copper to get the same effect.

And in regards to oxidation stainless steel is stainless due to a layer of chromium oxide on the outside. Copper on the other had takes quite some time to oxidize and due to the acidic nature of wort any oxidation that may have formed will be cleaned off.

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I don't know the formula to calculate heat transfer, but "k" has to be taken in relation to the amount thickness of the tubes' walls. And dismissing concerns about oxidation is not so simple, because the acidity of your wort moves the oxidized material from the coil into your beer.


I'd be interested in a SS counterflow chiller. It frieghtens me to see blackish green plumes coming out of the tube when the first bit of cleaner washes through. I just have to wonder what the cleaning process leaves behind.

ThriceIn5Minutes said:

I'd be interested in a SS counterflow chiller. It frieghtens me to see blackish green plumes coming out of the tube when the first bit of cleaner washes through. I just have to wonder what the cleaning process leaves behind.

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If you sanitize with StarSan (which is acidic) it probably eliminates most of the oxide before your wort hits the copper.

Still, I feel you...I didn't like that my copper IC looked dark and nasty going into the wort, and clean coming out! (And then dark again, when I go to use it a few weeks later.) The stainless one eliminates that concern, and works just as well in my estimation. If there is a difference in cooling time, it's measured in seconds and negligible.

the ss chiller from Midwest works great. Saying it won't work is bad physics...send those boys back to thermo class.

can you buy stainless steel coils or pipe? i made my imersion chiller from copper pipe for less than 20 bucks....can the same be made with stainless as easily...think about bending?

i would think you would not be able to bend a stainless tube on your own. Copper is easy to bend. MY wort chiller is not as pretty as some, but it works. The only thing I would change is that I would add more copper next time and a larger size tube.

My guess is they're switching to stainless because the price of copper is so high right now ($2.90/lb copper vs. $0.80/lb stainless). If I didn't already have two I would buy stainless and test it out.

jcarson83 said:

My guess is they're switching to stainless because the price of copper is so high right now ($2.90/lb copper vs. $0.80/lb stainless). If I didn't already have two I would buy stainless and test it out.

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Precisely why it is happening. The markey is crazy right now for copper. I bet they are making a killing on the Stainless chillers. If it does the job I am all for cheaper.

I'm also in the market and was interested in the differences, so I did some quick heat transfer calcs:

Conductivity of copper is ~401 W/m*K compared to ~14.9 W/m*K for stainless, but the convection (both inside and outside the tube) is far more significant. Assuming a wall thickness of 0.035", a tube OD of 3/8", a convection coefficient of 200 W/m^2*K for both fluids (inside and outside of the tube - wort can be approximated as water) and using the above conduction values, 3/8" copper tubing transfers heat at about 1.22 times the rate of stainless.

So, a copper 3/8" wort chiller is about 1.22 times better than a stainless one in terms of heat transfer.

I'm probably going to go with the stainless anyway, just for cleaning and aesthetics (the rest of my system will be stainless).

I'm going with a stainless one that will be mounted in my brew pot with fittings going through the side of the pot near the top.That way once your boil is done,just turn on the water and start cooling,the lid can stay on.

From "Hoosierbrewer"'s post: "I would like to see the results of a test."

This, and with metrics; we've had plenty of speculation as to which would be better. Let's get a test involving two identical (same length, tubing ID) chillers, with the same ambient and input water temperature and flow rate, same rate of stirring of the wort, and see the results. My bet (speculation) is that the thinner stainless tubing will bring it into the ballpark of the copper.

Going to continue to use my old copper chiller. Why? I already own it.

my SS and copper immersion chillers work great. i know all the numbers for cooling and thermal conductivity, but i'm willing to sacrifice 4-5 minutes of my time for the SS immersion chiller to cool versus the copper. The inability of being able to see inside my old copper IC was enough for me to switch to SS. It is a personal choice, really. Copper works better, but there are cleaning issues, and SS takes insignificantly longer to cool (no biggie), but i know i can get it perfectly clean every time, inside and out! If you choose to use a copper one, great! - I used one for a long time, but i got a deal on a 50' coil at McMaster Carr, and snagged it.

As far as the cooling times, my experience is that as long as i have a good whirlpool in my boil kettle (using my pump), my cooling is pretty much the same, plus or minus a couple minutes. Yes, copper is faster, but for the 5 gal batches i do, the differences are nil.

Look at the big breweries and large biotechnology companies and see what they use for heat exchanging (not plate heat exchangers, the exchangers in the tanks)- it is always stainless. Ask yourself why this is? Even if copper was that much better (25X) and there was NO worry of cleaning or other issues with copper, then we would see a lot more copper in the kettles and/or tanks. The fact is that SS is always used in these situations after careful considerations of all of these factors.

Bottom line, either is fine.

Briano said:

I'm going with a stainless one that will be mounted in my brew pot with fittings going through the side of the pot near the top.That way once your boil is done,just turn on the water and start cooling,the lid can stay on.

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This is off topic but, you may want to rethink the part about the lid. Most folks will tell you that you should not use one on your kettle when boiling your wort. Using a lid will make it hard to stir and thus circulate your wort around the chiller when chilling.

I have a stainless steel IC from nybrewsupply. It works great I would recommend it, and nybrewsupply, to anyone. The comparison of the thermal coefficients for copper and stainless are pretty much irrelevant in determining the effectiveness of each type of chiller. The stainless works very well. Copper may be slightly faster, but not significantly so. Neither material is perfect. You pick which set of advantages and disadvantages you deal with when you select either one. But I like the stainless.

Used a 50' 1/2" stainless IC. Works ok and cleanup is simple, rinse off with water after it's done the job. No tarnish, no green crap, no worries. I got talked into a copper one. Damn thing is tarnishing and getting ugly. I have to clean it before each use because I don't want that crap going into my brew. I'm selling the copper one and sticking with SS

Edit: not selling, will use it as a prechiller next summer.

I have a SS cooler and it works pretty well. I am assuming it has thinner walls than the copper coolers. As a benefit the SS doesn't oxidize.

I have the Mid-west SS coil, it is awesome on my keggle setup. As far as I can tell it seems to work just as good as a copper coil, its really easy to clean, and not that it matters, but its doesn't stain either. Also, MUCH more durable than copper.

You won't regret buying one.

The thing that the naysayers are forgetting is that a ss coil works just fine in a herms system, this is just the opposite. These chillers will last a lifetime and stay looking like the day they were new.

Well, this thread convinced me to go with SS for my immersion chiller. I got a 3/8" X 50' chiller. I'm stoked for it.

I have SS and had no problems, works like a charm, easy to clean, durable.

I have a SS chiller simply because I didn't want to deal with any oxidation in the future. I had used copper callers before but never liked how they would oxidize over time. For a 5 gallon batch, the time to chill is small.

I use an inlet hose of about 6 ft and wrap that into a coil in the sink filled with Ice water then into the chiller. With that setup, I am able to get wort down to pitching temp of 68 deg in about 18-20 minutes. With stirring, i get It down just a few minutes faster. Without the Ice bath, its about 25-28 minutes.

Overall both work great, with copper being a slight bit faster, but for me, cleanliness was important.

I just got a stainless steel immersion chiller for Christmas. I was wondering about one thing. I had the idea of bending the coils to make an overlapping/alternating pattern to spread out the coils.

First off, can anybody tell me if this actually has an impact on the chilling ability of the IC? Secondly, if I go for this, do I have to worry that the coils will crack/break as I try to bend them?

b33rm3 said:

It all boils down to the thermal conductivity coefficient 'k'

k for stainless steel 16 W/m*k

k for Copper 401 W/m*k

http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html

copper is roughly 25 times more thermally conductive. Meaning that one would have to use about 25 times more stainless than copper to get the same effect.

And in regards to oxidation stainless steel is stainless due to a layer of chromium oxide on the outside. Copper on the other had takes quite some time to oxidize and due to the acidic nature of wort any oxidation that may have formed will be cleaned off.

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While this is a valid point you have to understand that the thermal conductivity of the metal here is not the issue, the greatest limiting factor is your transfer coefficient on the wort side. Since it is an immersion chiller IF there is no agitation your transfer properties won't be so great on the wort side, internally since most folks have water flowing rapidly the transfer coefficient against the internal wall of the chiller will be pretty high. Also remember that the thermal conductivity can be looked at in therms of the thickness of the material, with the dimensions we are working with here the resistance posed by the metals is damn near negligible.

Unless you make your immersion chiller out of glass you need not worry.

I've had my eye on a stainless CFC from William's for a while. I like the idea of being able to run almost anything through the thing to clean it.

http://www.williamsbrewing.com/STAINLESS-CONVOLUTED-COUNTERFLOW-CHILLER-P3452.aspx

I should've made it clear I was resurrecting an old thread.

Anybody have ideas for me on how the stainless steel holds up to bending the coils to a staggered position or whether that will even be helpful anyway?

Be smooth about it and don't kink it. A little bit of stagger will theoretically help you because when you place the coil down all that surface area is no longer just contacting the next coil up, you are generating more exposed surfaces for wort (in terms of convection).