1/4" vs 3/8" immersion chiller

[SirCaptain]

I'm looking to make an immersion chiller. Right now I only brew 5 gallon extract and partial mash. I don't see myself going to 10 gal anytime soon. From what I've been able to read, it seems that most people stick with 1/4" or 3/8" tubing for their chillers. It sounds like with 1/2" you get too much water flow and not enough surface area in contact to cool the wort.

so, with 1/4" tubing being considerably cheaper than 3/8" (and therefore being willing to get 50' instead of 25'), I wondered if anybody had any good arguments for 3/8" over 1/4".

Thanks!

 

[tomije87]

I'm not sure where you read that about the 1/2 in, but it's been working great for me. I would imagine that you'd need an awful lot of 1/4 tubing to be effective. Go w/ 1/2 inch and you likely won't be disappointed.

 

[JasonInBTR]

Everything I have read leans towards 3/8 being a good compromised between flow and surface area. If would be nice to see some real empirical data or a chiller throw down.

 

[Bulls Beers]

I did a 10 gallon batch on Friday with my 3/8 x 50ft and it work like a charm. I also have a 25ft x 3/8 for my 5 gallon batches, which also works great.

 

[Catt22]

Imo 1/2" od ftw

 

[lumpher]

i have a 50' 1/2" immersion, and i can cool a 12 gallon batch to pitching temps in 20-30 minutes in texas in july, and 10 minutes in january

 

[SirCaptain]

Does anybody have any thoughts on the 1/4"? A friend of mine has 25' 3/8", so I'm tempted to build a 1/4" and compare them. Not sure I want to drop the money on a 1/2 in. Thanks for the replies thus far.

 

[cobolstinks]

I have 80' of 3/8". I bought a 20' IC from midwest supplies, it worked fine for 5 gallon batches but I needed to add to it to get it to work in my keggle. I bought an additionaly 60' and soldered it to the original chiller. It doesn't look pretty now, but it cools 10 gallon batches in <10 min.

I would just start bigger. Don't buy a small chiller now because you are doing 5 gallon batches now. That chiller will be useless if you expand in the future, or you will have to do some soldering to make it practical.

 

[Atvar]

1/4" OD would only be like 60% of the 3/8" OD volume, thus taking longer to cool. The 1/4" really doesn't seem to be popular at all.

I just put together my chiller: 50' x 3/8" OD refrigeration tubing $50 at lowes, and $16 in garden hose fitting parts, so $68. I went with the 3/8" OD because I figure I can sell it pretty easy in the future or even go back and turn it into a counterflow chiller.

 

[Bobby_M]

1/4 is too small unless you're willing to run 2 25' coils in parallel.

 

[stratslinger]

I'm kind of intrigued by the idea of building your own Wort Chiller - and Atvar, going with your numbers it seems like one could build one with twice as much surface area as you could buy from NB or the like for roughly the same money...

So, how do you go about shaping the coils? Is there a specific grade of copper you need, one that's more flexible? Do you need to heat it up to make it more pliable?

 

[Bobby_M]

You can get more simple than this by bending the tubing to form the uprights, etc, but this is one way to go about it. It definitely answers at least one of your questions. The tubing type is refrigeration tubing and it's soft enough to form without heat.

 

[mwsenoj]

I found 50' of 5/8" refrig tubing on sale and made a chiller and prechiller with compression fittings. It uses alot of water bbut works very well. I think I payed less than $50 for the tubing and ~$20 for fittings that connect to a male garden hose. Do not go to Lowes or the Home Depot for fittings, I have found them to be very expensive. I ordered the fittings from a place called Ferguson who works mostly with contractors and tradesmen. Good fair prices.

 

[arturo7]

1/2" gives you more surface area, more thermal mass, and allows more flow; thus better cooling.

 

[Keystyles]

well i typed out a whole thing last night to mathematically analyze the differences but it's not here so something must have gone wrong, and i'm not going to do it over, at least not right now. But to sum it up, assuming an 87 C temp difference (100-13) the max amount of energy capable of being carried away via flow rate (is just googled "flow rate copper tubing") would be...

1/4 = 5.1 kJ/min
3/8 = 10.3 kJ/min
1/2 = 16.5 kJ/min

The max amount of energy capable of being transferred via the surface area would be very roughly

1/4 @ 50' = 899 kJ/min
3/8 @ 25' = 674 kJ/min
1/2 @ 25' = 899 kJ/min

as you can see, the SA is capable of transferring far more energy than the flow rates are capable of sustaining so the major factor is flow rate. Be advised though that i could not find and was not willing to calculate the overall heat transfer coefficient for this application so i used one for non moving water at 25 C for a 1 C change which means there is a good bit of inaccuracy in the amount of energy transferred via SA but with a scale of difference in the numbers i think its a safe assumption that heat transfer is greater than flow rate here.

my last post included links which i am now thinking probably got it flagged for review or something like that, if it does get posted you will see a bit more of the math and where i got my numbers. I have changed the math slightly to give kJ/min for both for easier comparison for our specific application. Perhaps an engineering forum would be a good place to ask this question since an actual engineer would be better suited to find the answer than I am.

 

[Scooby_Brew]

I'm looking to make an immersion chiller. Right now I only brew 5 gallon extract and partial mash. I don't see myself going to 10 gal anytime soon. From what I've been able to read, it seems that most people stick with 1/4" or 3/8" tubing for their chillers. It sounds like with 1/2" you get too much water flow and not enough surface area in contact to cool the wort.

so, with 1/4" tubing being considerably cheaper than 3/8" (and therefore being willing to get 50' instead of 25'), I wondered if anybody had any good arguments for 3/8" over 1/4".

Thanks!

I like the 3/8''. I use 50' long 3/8" OD copper tubing for 10 gal batches. That's what I use now, and I am happy with it. My guess is for 5 gal batches you could use 25' long 3/8" OD tubbing.
My first IC was 1/2'' and it was just too wide. After a while the water was coming out cold, while the wort was still hot, there just wasn't enough heat exchange going on.
1/4'' maybe too flimsy - you want to be able to stir the wort with your IC once a while to speed up the chilling process. 1/4'' may bend or brake when you do it.

 

[CidahMastah]

+1 on the 1/2. I have a 50ft 1/2 IC and I don't think I will ever out grow it. about $90 at HD in parts.

from boil to 75F in about 12 minutes. I only do 10-11g batches

 

[Jubilee]

I just ordered a 50 ft 3/8" stainless steel IC with garden hose attachments from Amazon. Decided to pop for stainless...well, because all my other stuff is stainless. Why stop now? :rockin:

It came to $85 with shipping. Not bad after I considered DIY copper with purchase of flux, solder, torch, etc...

http://www.amazon.com/dp/B004XWBRBM/?tag=skimlinks_replacement-20