immersion chiller

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fire943

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I have a prewort immersion and wort immersion chiller. The problem is it takes from flame out to hitting 74 degrees around 90 minutes. I live in florida so the water is pretty warm but the prewort immersion is sitting in an ice bath. The water runs slower to absorb as much cold/heat as possible. Any one have ideas or tips to reduce the time to cool the wort? Thanks:tank:
 
I have a prewort immersion and wort immersion chiller. The problem is it takes from flame out to hitting 74 degrees around 90 minutes. I live in florida so the water is pretty warm but the prewort immersion is sitting in an ice bath. The water runs slower to absorb as much cold/heat as possible. Any one have ideas or tips to reduce the time to cool the wort? Thanks:tank:

Increase the speed of the water. The bigger the difference between the water and the wort, the faster it will chill. The slower the water flows, the warmer the water gets, slowing chilling down.
 
What size are these chillers? If we know how much flow you have and the temp of incoming water it would help.
 
I hooked up an aquarium pump to mine, and run it out of a 5 gal bucket with ice water in it. Run the first 2-3 bucket fulls right out before you add the ice or else you'll eat up the ice too fast. After that, my ice bath kills it quick and I don't waste tons of water. Just have a bunch of ice ready. I make blocks in tupperware containers in the freezer.
 
Increase the speed of the water. The bigger the difference between the water and the wort, the faster it will chill. The slower the water flows, the warmer the water gets, slowing chilling down.

I disagree, if the water flow is too fast then chilling will not be efficient, think of it as an engine, if you take the thermostat out it will not cool as efficiently because the water is circulating too quickly, to efficiently carry heat away with a thermostat, the water is restricted, absorbing more heat than without, and in effect increasing the efficiecy of the cooling.

I recirculate ice water through my IC, and at 900 gph the flow isn't too fast, but it is not too slow either, I was looking for a pump that would circulate faster (~1400 gph), but I think thie model I have with a leser gph is actually more efficient.

The hot water is carried away more efficiently.
 
I agree with the previous post. It's all about temperature differentials and contact time. If you have ice-cold water moving through your chiller at the speed of sound, it won't have much time to transfer the heat from the wort.

An anecdote may help clarify. I bought MW's entry level 25' copper wort chiller two years ago. It's a good unit, but hard to get the hose clamp union where the vinyl hose meets the copper chiller to stop leaking. This summer, when I went AG and moved my operation outside, I decided to refit the chiller with compression / garden hose fittings. When I took the original clamps and hoses off, I noticed that there is a plastic tape inside the copper tubing of the chiller, evidently running the full length. I was quite puzzled by this, thinking that it could only slow the water flow down, and that was bound to be a bad thing. I e-mailed MW, and in the reply, they told me that the plastic tape is put into the tubing on purpose, and the purpose is to slow the flow down. The e-mail said that without the tape, it would actually take 15% longer to cool the wort. This ensures better transfer, not so much from slowing the flow, but in mixing the cold water as it flows through the tube, ensuring the maximum contact with the walls of the tubing. As everyone knows who's done chilling for any length of time, it proceeds more quickly the more you stir the wort. Think of the plastic tape as stirring the water inside the copper tubing, as you stir the wort outside. This maximizes the temperature differential on both sides as the liquids exchange heat through the copper.

{NB: I'm just SURE some engineer can explain this more concisely, in a few well-chosen equations that I would never understand. I've tried to give my own explanation, as best I understand the process.}
 
Well first of all you dont want to run the pre chiller at the beginning. Just run the wort chiller to get the wort down to low 100's F. Then use the pre chiller to get it down to 80 or 70. I live in Texas and I know how hard it is to get it below 90. The prechiller will help with that.

As for the water fllow, you'll have to play around with it. I usually feel the output water , if it doesnt feel close to the temp of the pot, I will decrease the flow. You also want to stir while its cooling. This will really help you get it down quickly, or atleast lift the wort chiller up and down, not so much to oxidize it, but enough to move the cold /hot wort around.
 
I disagree with the two posts disagreeing with me. Er. Well, I don't disagree with what you wrote, I disagree that you disagree with me.

The problem is the difference between efficiency and speed. Faster flow will chill wort faster. The process, however, will become very inefficient. To make a not-very-relevant analogy, imagine the gasoline flow in your car. As you increase the flow, you will go faster -- but less efficiently. Likewise, too fast a flow in a chiller will chill wort quickly, but not since we don't want to create 100 gallons of wastewater to chill 5 gallons of wort, there's got to be a reasonable limit.

My comment was based largely on the original poster's comment that he runs the water "slowly" to absorb "as much heat as possible." While he is maximizing the heat absorb per unit of water, he is using less water... While I don't know how slowly he is running the water, it sounds to me as if he's running it quite slow, and that's probably why he's not getting a good chill.

As far as the tape in the chiller story, MW confused you. They said the purpose of the tape was to slow the water down, then they told you the tape improved efficiency by mixing the water, not by slowing it down. They were right the second time; there's no reason to intentionally slow the water down, but if you can improve mixing considerably while only slowing the water down a little, it's a very good trade-off.
 
I use the same method, living in Georgia.

The two best things you can do are:

1) As JessRC said, don't use the ice bath until you hit 100 deg

2) MOST IMPORTANTLY!!! - You can't just let the chillers sit still. If they do, they chill only the water immediately touching the coils. Try this - run some water through you ice bath chiller and feel the water coming out. Then, "bounce" the chiller in the ice bath and now feel the water coming out. It will be 10-20 deg colder. The same thing goes for the wort chiller. I constantly/gently swirl the wort chiller in the kettle with hose water until I hit 100 (about 15 min), then hook up the ice bath chiller (bounce it) and continue to swirl the wort chiller. In about 15 more min, I'm usually down to 75 deg. It's a little tiring, but you're chilling in 30 min (full 5-6 gal batches) and getting a good cold break.

Let me know if it works.
 
Here is my method that will chill the wort to 65F with 70F tap water. When I have completed my mashing and during the boil, I empty and wash out my MLT cooler, 48 qt. I now fill it with ice and a small amount of water. When finished with the boil and all my hop additions, I start the flow thru my 25ft 1/2 coil IC. When the the wort temp gets below a hundred, I route the waste hose back into the MLT which sits above the boil pot. This forces about 5 gallons of water into the ice. Then I unhook the hose and let it siphon back thru the IC. Now I have 33F water going back thru the IC .Works awesome and I conserve some of the waste water.
 
I use the same method, living in Georgia.

The two best things you can do are:

1) As JessRC said, don't use the ice bath until you hit 100 deg

2) MOST IMPORTANTLY!!! - You can't just let the chillers sit still. If they do, they chill only the water immediately touching the coils. Try this - run some water through you ice bath chiller and feel the water coming out. Then, "bounce" the chiller in the ice bath and now feel the water coming out. It will be 10-20 deg colder. The same thing goes for the wort chiller. I constantly/gently swirl the wort chiller in the kettle with hose water until I hit 100 (about 15 min), then hook up the ice bath chiller (bounce it) and continue to swirl the wort chiller. In about 15 more min, I'm usually down to 75 deg. It's a little tiring, but you're chilling in 30 min (full 5-6 gal batches) and getting a good cold break.

Let me know if it works.

Thanks. I will. How long does it take you to go from flame out to 100 degress??
 
This may be a dead issue now, but I keep seeing this argument pop up.

FASTER CHILL WATER = FASTER WORT CHILLING.

There's no two ways about it. In terms of efficiency, yes, faster is bad, because your BTUs of heat removed per liter of water will go down. In terms of SPEED though, faster is better. You'll waste more water, but you'll also make your wort drop in temperature the fastest.

As already said, heat transfer depends on temperature difference, (that's it, there is no heat transfer formula that has "how fast are the two objects moving?"...all that matters is temperature differential, thermal contact, and heat transfer coefficients at the interfaces). You will get the best heat transfer at the biggest heat differential. You get the coldest chill water all the way through the chiller if you run it FAST.
 
Sorry to hijack the thread, but I am planning on making my own chiller. I was just wondering if just a 25' coil of copper from home depot is ok? I am planning on making all my own unions for attaching to a tap and so on.

Thanks for the help
 
Sorry to hijack the thread, but I am planning on making my own chiller. I was just wondering if just a 25' coil of copper from home depot is ok? I am planning on making all my own unions for attaching to a tap and so on.

Thanks for the help

I use a chiller made from 25' of 3/8" copper. With 55F well water, it will reduce 5+ gal. boiling wort to <70F in 20-21 min.....which is plenty good enough for me.

I should also note that I stir the wort a LOT during that time; you'll never get times that short if you don't.
 
A question to add-on to the end here... I just made my own immersion chiller using the DIY projects section. I've tightened my compression fittings as tight as they possibly could go and the joints still leak a little bit between copper and fitting. Any suggestions??? (more of a plumbing question than a homebrew question, sorry!)
 
Try putting a little pipe dope (joint compound) on the ferrule. It can be difficult to get a good seal on soft copper sometimes. It has a way of getting out of round while your working with it and compression fittings don't like that. Try soldering, there's really nothing to it. Just watch a quick video on YouTube and you'll be fine. Seriously. Coiling it is more difficult than soldering.
 
A question to add-on to the end here... I just made my own immersion chiller using the DIY projects section. I've tightened my compression fittings as tight as they possibly could go and the joints still leak a little bit between copper and fitting. Any suggestions??? (more of a plumbing question than a homebrew question, sorry!)

I had the same problem--fixed it w/ SS wire wound tightly around the hose for a greater psi pressure. No more leaks.
 
Thanks. I will. How long does it take you to go from flame out to 100 degress??

Lately, I've been brewing on days that were 77-80 deg and to go from boil to 100 (with bouncing/swirling) has been taking about 15-18 min. Once the ice water chiller is hooked up, it's about another 15 min to get down to around 70-75 deg. I definitely think there's a trade-off with the speed of the flow. That, you kinda have to play around with.
 
Very good suggestions here. On my first batch my shiny wort chiller didn't meet expectations. I went from flame out to 90F in 15 mins. When the wort got close to my groundwater temperature the chilling just stopped. I wasted a bunch of water and about an hour and a half waiting to get under 80F.

I made sure to remedy the situation on the second batch. I ran the garden hose through the chiller for the first 15 mins and back to 90F again. Then I put a 1/6 HP sump pump in a cooler of ice and hooked it into my chiller supply and ran the chiller output back into the cooler. I hit 70F 8 mins later. Very pleased with this result. Many thanks for the cooler and pump idea found on this forum.
 
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