Wort Chiller

[d40dave]

I have a copper wort chiller. I have read that copper is not good for beer. My copper wort chiller seems difficult to keep clean also. I have this:
https://www.amazon.com/NY-Brew-Supp...1&keywords=wort+chiller&qid=1609793527&sr=8-1They have the same thing in stainless steel. I was wondering if it will cool the wort as well as the copper one. I have no problems with how the copper one cools. Thanks.

 

[Knightshade]

Cooper will cool the wort faster than SS. Some LODO brewers will tell you to stay away from copper, but unless you're willing to invest in the entire LODO process, removing 1 piece of equipment isn't going to impact anything. My $.02

 

[tripeland]

Copper conducts heat much quicker than SS and will result in faster cool down rates. On saying that, many SS chillers have thinner walls due to higher strength, so the heat transfer can be similar (but still not quite as good as copper).

SS sure is easier to clean!

 

[d40dave]

If cleaning a SS WC will save me some time cleaning it and keeping it clean then it may be worth switching. I think I typically spend about 15 minutes cooling the wort. It's dependent on the time of the year and what final temperature I want. Would switching to SS increase this much, 5 minutes?

 

[Vale71]

Would switching to SS increase this much, 5 minutes?

Copper has a thermal conductivity about 20 times that of stainless, so unless your SS chiller has a wall thickness 1/20th that of the copper one (mechanically impossible) it's going to take a lot more than just 5 more minutes.

 

[Birrofilo]

Last time I measured that, with my SS chiller it took 10 minutes for slightly than 20 litres wort from boiling to ambient temperature. I go by memory but I remember it was very fast. The chiller remained for almost half its lenght above the wort because the kettle was not full.
The "secret" in making the heat transfer fast is to gently use your paddle to move the wort around the chiller with a "counterflow" movement. Just observe the direction of the water in your chiller, and make the wort move in the other direction.
Also, the cold water should flow from the top of the chiller downward, you will have different results depending on how you connect your chiller to the water source.

What is important is not only the heat transfer of the metal but also the maximization of the interaction between the cold water and the wort. If you just let the water work, and leave the chiller untouched, the wort in contact with the chiller will get colder but will also "isolate" the rest of the wort from the chiller.

Next time I will pay attention again because I am surprised by the discrepancy between your results and mine.

 

[KeizerBrewr]

Short answer, no. Copper is far more conductive than stainless steel. Keeping your IC clean shouldn't be too difficult? I spray mine off with water, give it a scrub if really needed and stow it until next brew day. On brew day, I toss it into the brew kettle the last five minutes or so of the boil.

 

[chipmunk]

They have the same thing in stainless steel. I was wondering if it will cool the wort as well as the copper one. I have no problems with how the copper one cools. Thanks.

The thermal resistance of either stainless or copper is small compared to the thermal resistance in the boundary layer between the wort and the metal. That’s why you see a major improvement in cooling times on either type of coil when you agitate your wort. I think they will perform similarly - particularly if you’re not agitating vigorously.

 

[tomk2021]

I ordered a 25 ft. copper chiller from NB. They were out so they subbed it with a 50 ft stainless chiller. I couldn’t be happier with it. The extra length more than makes up for any differences in conductivity and it is a breeze to clean!

 

[chipmunk]

Just to elaborate on this, you can use the engineeringtoolbox calculator to estimate the overall heat transfer coefficient.
https://www.engineeringtoolbox.com/overall-heat-transfer-coefficient-d_434.html
So for a 50 foot 1/2” coil I get 0.6m2, using a temp diff of 100dC and 10dC and a 0.001m thick tube wall...
The hci and hco are the convective heat transfer coefficients that range from 50 to 3000 in natural convection states, and much higher for forced convection (I.e., turbulent flow). So if I assume hci of 3000 w/m2*k (cuz you’re pumping cold city water through the coil) and say 500 for a non agitated wort on the hot side, you can see that the thermal conductivity of the heat exchange material makes very little difference.
overall hc = 428 for copper, 425 w/m2*K for stainless.

If we assume agitating the wort, and increase hco to say 2000 we get 1196 for copper, 1169 W/m2*K for stainless.