My CFC copper pipe split have to make a new one - help sizing it right?

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Jan 24, 2017
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Plymouth, MN - terrible tap water for brewing
Some years ago I made a Counterflow Chiller like the JaDeD Cyclone. Mine worked great, but I made it from used copper pipe, and/or must have left some water in it over the winter. A couple of the short connecting pipes split. It will be too hard to take apart and fix, and considering I made it with used pipe in the first place - should just start over.

Looking at the JaDeD Cyclone, they don't recommend chilling from brew kettle to fermenter due to long chill times. They advertise their chiller as 12' of 1/2" copper pipe and when using it to recirculate 5 gallons, it takes about 8 minutes to chill to 10F above source water temps.

My old chiller had about 20' of 1/2 Copper Pipe wrapped inside 3/4". I also soldered a piece of electrical wire around the outside of the 1/2" pipe thinking (hoping?) that the agitation would increase efficiency. Not sure if that actually helped or not. I had to have very low flow rates to get a 1-pass chilling from around 200F to 70F, so I understand JaDeD's comment about not advising 1-pass chilling.

I brew 10 gallon batches and would really like to do 1-pass chilling if possible. I'm in MN, so our ground water is pretty cool in the summer, and downright cold in the winter. I'm thinking about bumping a new CFC to 30' total, but with the price of copper pipe, want to be as thrifty as possible.

I tried the Microsoft Copilot AI thing and asked it:
I have 10 gallons of wort at 200F. I want to cool it down to 70F within 10 minutes using a counterflow chiller. The counterflow chiller is made of .5" standard type M copper pipe inside .75" standard type M copper pipe for the heat transfer. The wort is pumped through the .5" pipe at 1 gal/min and the 50F cooling water flows at 4 gal/min in the opposite direction through the .75" pipe for the heat transfer. How long does this counterflow chiller need to be to get the 10 gallons of wort from 200F down to 70F in 10 minutes?

It came back with this:
Certainly! Let’s calculate the required length of the counterflow chiller based on the given parameters.
  1. Heat Transfer Rate (Q):We’ll start by calculating the heat transfer rate using the formula:
    • Initial wort temperature = 200°F
    • Final wort temperature = 70°F
    • Flow rate of wort = 10 gallons per minute
    • Specific heat capacity of water (wort) ≈ 1 BTU/lb·°F (approximately)
    • Calculate the heat transfer rate (Q):

I change the question many times to give me an answer in feet. I also asked to calculate length needed at both 40F and 50F cooling water temp at a flow rate of 3 gal/min and 4 gal/min.
40F at 3GPM = 18.7 long
40F at 4GPM = 17.5' long
50F at 3GPM = 17.5' long
50F at 4GPM = 17.5' long

I certainly may not know the best questions to ask. I know those answers can't be correct (all the same length).
Any thoughts on how many total feet I need to make the chiller?
What's the importance to you as far as the one pass? I predominately whirlpool my finishing hops rather than flameout. That provides an initial drop and chilling from there to ale pitch temps is fine. Even not whirlpooling and straight to chilling is usually fine with my CFC. It's not the same as the one you are building. What I'm saying though is that a short cooling recirc is little difficulty on my rig, just a hose change. Maybe it's more trouble for your setup?

I have a 3 vessel 2 pump EHerms. My current CFC is like the one linked below. Because I have a hopstopper, I can't pump full out, so I can't really give optimal cooling time but it's about a gallon a minute. However, I bypass the hopstopper on the recirc using a second drain valve. The drop to whirlpool is hands on quick. Pump on watch temp drop closely, get within 10 degrees, count about 5 seconds or so turn off the pump.
Let me add, I temperature control fermentation so being within a reasonable range of fermentation temperature is fine if I don't hit it precisely. Also 85-90% of the time I'm doing 6 gallon batches.
Extra info I should have added...
I am not set up for it and don't whirlpool.
I used to control fermentation temps in a plastic conical but sold that setup and saved a lot of floor space (sold the a/c unit and cooler and table it was on, SS coil, conical fermenter w/heat tape on it) and now I pressure ferment in corny kegs. Ferment temp control is not critical now. Only pitching temp.

I suppose I don't need to do 1-pass cooling, but if I'm building another CFC from scratch I thought it might be nice to save some minutes on brew-day. I could recirculate in the brew kettle for a while first before pumping into the kegs. It would simply be connecting the hose back to the kettle lid instead of pumping into the keg.

I think you talked me into not worrying about it and just recirc for a while first before pumping into kegs.
I couldn't tell you whether the AI was doing it right but I figured I could make it less troublesome if you were off just a little bit.
I've found chilling with recirculation down from boil to around 120-140F going fast, using regular tap water, even in Summer.
I then change to ice water and chill directly to the fermenter, adjusting the wort flow based on outlet temp. It's not the fastest but it works better than anything else I've tried.

I use a 30-plate chiller.

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