Counter-Flow Chiller Length??

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JungMin

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I am building a counter-flow chiller.....what length should I build? I will be buying 50' of copper pipe, but is that over doing it a bit?? I see lengths of 25', so maybe 50' isn't needed and will slow the flow rate too much??

Also, how do people connect the chiller to the wort?? What kind of hose should I use to move the boiling wort to the chiller??

Thanks.

I started a thread in the DIY area....my appologies as it should be here i think.
 

Kauai_Kahuna

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It depends on the volume your cooling really.
Correction: I used 25' of copper.
I used 15' when I built mine and it worked great for extract brewing and I could chill my wort in 15 minutes, as I have moved to AG and trying to chill 6 gallons, it takes around 30 minutes, and that is running tap water till it gets down to around 110F, then I recirculate iced water through it. I now wish I had built it with 50'.
 

beerthirty

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according to Bobby_M with 25' the difference in coolant temp and wort temp is only one degree, which is just about the best efficiency your going to get. But I'm a bit hammered now and cant seem to find that link to pass on to you. Mine is 25' and seems to work great, but I recirculate through an ice bath since I live in the desert and cant get less than 80-85 out of my tap.
a pump or a SS racking cane.
 
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JungMin

JungMin

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I'm thinking about drilling a hole in my pot and hooking up a valve and spout type thing. My plan was to connect the pot and the chiller via a plastic hose (spout/valve to chiller), but i'm now thinking that the temperature of the wort will be too hot for the tube?? But I don't know how else to connect them.
 

Kauai_Kahuna

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I'm thinking about drilling a hole in my pot and hooking up a valve and spout type thing. My plan was to connect the pot and the chiller via a plastic hose (spout/valve to chiller), but i'm now thinking that the temperature of the wort will be too hot for the tube?? But I don't know how else to connect them.
Silicon tubing, high end and expensive, or risky re-enforced tubing, (little metal strands in the tubing. I use the re-enforced and no problems so far.
 
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JungMin

JungMin

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Well, I went out got all the goods.

They shop wouldn't sell me anything other than a roll of the 3/8" tubing....So I have 15m (50') of it for $28. So I picked up 15m of garden hose while i was at it (only $10).

So, I guess I will make 2 and try to sell one. If Bobby_M is correct in saying...
with 25' the difference in coolant temp and wort temp is only one degree
...then regardless of the size of your batch, there is no need to go any larger than 25'. It will actually slow the process as it would just take longer to syphon the wort through the chiller.

I've had a couple pints, but am I correct in thinking this??
 

Bobby_M

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Yup, as I mentioned in the PM, I'm having conflicting results between the last two batches and I'm trying to figure out what else changed.

A couple weeks ago I was running wort out of the CFC at 63F and I measured the tap water at about 63.5F (I was using two differnent thermos so even if we're talking +/-1F in either direction let's say my temp delta was less than 4F between the coolant and wort output.

In my last batch I had 78F wort coming out with a measured coolent temp of 68F. Wow, how did the delta go up to 10F now? In both cases I was running the coolant at full and the wort at about half. I even tried slowing the wort down to a trickle and it wouldn't get any colder.

Some other ideas.... I know that these chillers are most efficient when the entire wort coil is filled with no air gaps and when the coolant chamber is also full of water with no air gaps. There's a slight chance based on the flow rate of the wort and the elevation of the chiller (on top of my HLT) that I didn't have the coil full.

I need to boil up some water to try this again.
 
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JungMin

JungMin

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Well, I just finished running my new chiller through a test run. I made it from 25' of 3/8" copper tubing in 5/8" reinforced garden hose....seems to be the standard setup.

It came out looking pretty good!!! I added fittings to connect it to the ball valve on my brew pot and one to connect to directly to line coming out of the kitchen sink. Makes it easy as pie to set up!!!



Boiling water was running into the chiller while to coolant (tap water at a high flowrate) was flowing in at 24 degrees celsius. The coolant was coming out at 35 degrees celsius while the 'wort' was coming out at an AMAZING 24 degrees celsius!!!! Yes, the same temperature as the coolant!!!!! Ok, it might have been a 1/2 a degree off but close enough. I can't believe how well this think works.....It's bloody amazing!!!!

Thanks everyone for your help in getting me started!!!

Edit: Did another test run. This time with the boil pot about 1m above the chiller. It was running pretty much exactly a liter per minute. That's just siphoning. I think there was some air trapped in the setup as it was gargling a bit. Temps were pretty much exactly the same.

Without using a pipe, any ideas on how to get a better flow rate??
 
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JungMin

JungMin

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After a few pints and some deep thought, I realized that I wasn't actually siphoning the 'wort' (just hot water for the test). It was just flowing through the chiller by gravity, so flow was being obstructed by all the air in the line. So, I flooded the chiller and all tubing to get a proper siphon going....

Well, this really got the flow going. It's now flowing at 2.5L/min!!! That's a full boil in just over 9 minutes!! Of course this higher flow rate has an impact on the temperature of the 'wort' coming out of the chiller. I am only getting it down to 29~30 degrees celsius. My tap water (city water) was around 27 degrees celsius.

So, I lost about 5 degrees in cooling while increasing flow 2.5 times. I'm not sure if the relationship is linear or not, but maybe slowing the flow to around 2L/min will get me down into the 27 degree range - I'm hoping anyways!!
 

adrock

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If I'm not mistaken -- and it's entirely possible I am -- you're going to get less impressive results when you actually use wort. Since the wort is a sugar/water solution it will have a higher thermal mass than water.......it will essentially be a better insulator than water, and will not be able to transfer heat to the coolant fluid as effectively. Furthermore, boiling wort is hotter than boiling water, so it will have much more heat to give off before getting down to pitching temps.

I'm not saying it won't be good enough; you'll have to try it and find out. Just wanted to poop all over the party. :(
 

Grimsawyer

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I made one with 50 feet of 3/8" copper and hose.... omg... wanna talk about OVERKILL!!! Not to mention but the rate of water coming out of my hose outside is very impressive. That being said in winter months my wort is coming out mid 50's F WITH the valve on my kettle cracked WIDE open and my pump pushing it through that chiller as fast as it can. IMHO 50ft is overkill. 25ft would be more appropriate but I've already put mine together and i LOVE IT!!!
 

drunkatuw

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Yup, as I mentioned in the PM, I'm having conflicting results between the last two batches and I'm trying to figure out what else changed.

A couple weeks ago I was running wort out of the CFC at 63F and I measured the tap water at about 63.5F (I was using two differnent thermos so even if we're talking +/-1F in either direction let's say my temp delta was less than 4F between the coolant and wort output.

In my last batch I had 78F wort coming out with a measured coolent temp of 68F. Wow, how did the delta go up to 10F now? In both cases I was running the coolant at full and the wort at about half. I even tried slowing the wort down to a trickle and it wouldn't get any colder.

Some other ideas.... I know that these chillers are most efficient when the entire wort coil is filled with no air gaps and when the coolant chamber is also full of water with no air gaps. There's a slight chance based on the flow rate of the wort and the elevation of the chiller (on top of my HLT) that I didn't have the coil full.

I need to boil up some water to try this again.
I noticed almost the exact results today while brewing. My tap water was 64.2F and the wort came out around 76F. When I closed the valve on my keggle to closer to half open, the flow slowed down and the wort came down to 72F. I need to look into a pre-chiller or something or maybe just wait until the tap water cools down in a couple months. In the winter I have to throttle my tap water because my wort comes out closer to 50F. I should note that my CFC is 20' long because I had the option to either buy 20' for $22 or 50' for $60 at Menards and I went for the 20'.
 

scox80

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After a few pints and some deep thought, I realized that I wasn't actually siphoning the 'wort' (just hot water for the test). It was just flowing through the chiller by gravity, so flow was being obstructed by all the air in the line. So, I flooded the chiller and all tubing to get a proper siphon going....
What do you mean by this...I think this is the problem I always have with my CFC. It always drains really slow. I have a 50' I made it that way cause I got the copper for free from a friend.
 

Bobby_M

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I think it's true that the higher gravity worts take more to cool. The beer I was having most trouble with was a 1.118 barley wine. I noticed when I went over to the second running beer, 1.050, it was chilling better.
 
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JungMin

JungMin

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What do you mean by this...I think this is the problem I always have with my CFC. It always drains really slow. I have a 50' I made it that way cause I got the copper for free from a friend.

Well, I could be wrong but it seemed to solve me problem.

I meant that if you just let the wort flow into an empty chiller (full of air), then I don't see that flow being able to rid the copper tubing of all the air; there just isn't enough pressure. So, the air is going to slow the flow rate by taking up some of the tubing volume.

So I thought if I first fill the chiller and connecting hoses with say One-Step, and then through the switch, you are basically siphoning the wort out of the brew pot. Low pressure is going to pull the wort through the chiller without pockets of air to slow the flow.

It worked for me....I went from 1L/min to 2.5L/min.
 
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JungMin

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If I'm not mistaken -- and it's entirely possible I am -- you're going to get less impressive results when you actually use wort.
Yeah, just did a batch and results with the wort were WAY different. I am kicking myself in the ass now. I had the materials to make a 50' chiller, but didn't. I really wish I did!!!! :(

To all those debating on whether to make a 25' or a 50', don't even think twice; MAKE A 50'!!!!!!!
 

Bobby_M

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Before you recommend a 50ft CFC, what was the temp of your coolant water and what was the temp of the wort coming out?

I guess there are pros and cons to the various lengths. In my pumped setup, a longer CFC mean more wort trapped and left behind (I flush it the best I can with some sanitary water but still). It's a bulkier piece of gear for sure if you go 50. What I'd really like to see is just how much better 50 is if all else is equal, wort temp, coolant temp, wort flow, coolant flow. If a typical delta on a 25 is say 6F, would it be 3F for a 50ft? I don't know.

The fact that I was running a delta of 1F on one batch and 10F on another just puzzles me and I'm positive there's something at play that I just haven't figured out yet. I do have it "counterflowing" for sure (which is one potential mistake you can make; running the wort/coolant in the same direction that is.)

Maybe there's just a threshold in coolant temp where you have to start using ice, period. I do get it though, there's got to be a chiller length (whatever it might be) where you can run the coolant and wort at full flow and there will literally be NO delta at all. That might be 100'.
 

WBC

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Bobby,

Using 25 feet is ok if you run it slow enough to get as much thermal transfer as possible. Warmer ground water just does not cool as well.

Using 50 feet is better because you have 2 times the length to get thermal transfer.

Diameter: The bigger you go the more surface area you have. I use a 50 foot 1/2 diameter and that has worked the best if any of the smaller or shorter chillers I have tried. More is better but it does cost more.

I brew 12 to 24 gallons at a time and so need the better chiller. For 5 gallons a 25 foot is OK.
 

Bobby_M

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WBC, I think you might be talking about an immersion chiller. Maybe you do have a 1/2 x 50' counterflow, but what are you using for your outer cooling jacket?
 
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JungMin

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I think it may be hard to peg it down exactly. Wort temperature, wort specific gravity, flow rates through the chiller, and coolant temperature are all thing I think are going influence the temperature at which the wort exits the chiller.

If you are lucky and have well or city water that is cold, this is really going to help you out. I'm not so lucky in that it seems my tap water runs between 24 degrees celsius and 27 degrees.

On the batch I brewed yesterday, I didn't do a full boil. After I brought the volume of water up to 23 liters, the wort temperature was just over 70 degrees celsius. Running this through the chiller with coolant at 26 degrees, the wort was coming out at ~28 degrees.

If the wort was running through the chiller at boiling temps, the exit temperature of my wort would have been MUCH higher i'm sure!! This is where one could appreciate the greater length of a chiller, especially in my case where my tap water isn't so cold. It would expose the wort to the coolant for twice the amount of time.
 

WBC

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Bobby, I am using both counterflow and imersion at times (2 boilers) I bought a 25 foot 3/8 imersion chiller to start and then bought the 50 foot half inch from Morebeer and bought the 25 foot counterflow which has the convoluted 5/8 copper inside 1 inch copper on the outside.
It seems their prices are a bit higher now but still not bad.

http://morebeer.com/view_product/19523/102204/Wort_Chiller_-_B3_5_10_Split
http://morebeer.com/view_product/19533/102203/Chillus_Convolutus_Counterflow_Chiller
 

GuateBrewer

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Anyone ever run the numbers on a 2 stage CFC for those with warmer ground water.

For sake of discussion a 30 ft internal coil with 2 sets of inlet-outlet T's. The first longer one for tap water (20ft?) (25ft?) which could do the bulk of the cooling, and a second shorter one (10?5ft?) which would be for use with the ice cold water be it a recirc poormans gylcol system or a pond pump in ice water. This seems like it would let you hit the final temp you want, while moving a bulk of the heat with cheaper tap water rather than ice water?

Seems like the extra set of fittings would pay for itself pretty quickly in Ice/Chilling costs?

Thoughts - Concerns, Suggestions on "Ideal" sizing and proportion of the two loops?
 

GearBeer

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I've never run the numbers on one with warmer water but I did a number of calculations for my research/industrial style CFC.

My calculations were based on my relatively cold well water and indicated that the necessesary length was much shorter than 25'. However, it should be remembered that my calculations represent a 100% efficient (read: physically impossible) CFC. If you're interested in investigating some different conditions I invite you to use my chiller calculation spreadsheet.

Since the question was brought up I improved the quality of the spreadsheet slightly. I added input cells (yellow) and marked the source of my density values in red.

Note: It is necessary to iterate to find the temperature of the outflow using this spreadsheet. The density of the water must be determined by interpolation for each iteration, see the engineering toolbox link for the necessary values.
 

hughmac

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To celebrate the grand re-opening of Schuylkill River Brewing Co. in our new location, I built a counterflow chiller. 50', big wooden stand painted gray. ~195F > 68F, don't know my flow rate though, and didn't measure the tap water temp. It was WAY too much work (three 5 hour evenings), but ended up being pretty sweet looking, and actually very functional. I could make another in a lot less time, too. :)

The porn shot:



In action (sanitizing):

 

hughmac

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You mean that annoying 16" x 16" section of floorspace in the garage that needs covering? Check.

LOL I'm Keeeding.
Pre-CISELY! :rockin:

My cellar is cracked, crappy concrete, and the chiller just perfectly covers a toe-stubbing hole. Good for when I'm brewin. :drunk: And happily you can put whatever you want on top of it too ... my stack of buckets goes there nicely.

Obviously the thing is ridiculous. Three nights just to build a chiller? I could have been watching TV! My wife thinks I'm bonkers. But it cools like a champ (just did a quick extract batch of dark German lager tonight) and fits in with my 'brewing is art' mentality.

And for you 'brewing is science' folks, some more data from the brew tonight: 192F wort > 68F ferment w/64F tap at about 1/5 flow for the water (didn't measure actual rate, but the know was nearly closed) and 5 gal/18 min flow for the wort.

Even though it's heavy (maybe 20lbs), it's one unit, which is cool. And I put those little screw in/out feet on it for stability and leveling.

If I were to do it all again, I'd make it about 1/2 as tall and more 'dense', with the coils all together as a unit. That would save serious time in construction of the stand ... all those slots were a pain. But the fact that I can put my kettle (or sani-tun) on top for siphoning is helpful.
 
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JungMin

JungMin

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Ya, looks great dude!!! Glad it works well too!!!
 

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