Immersion chiller and outflow water temperature

[Architect-Dave]

So, strange question, but I have to ask. When using an immersion chiller to cool down your wort, is it more effective to have the water that is being ejected be hot or cool? I am thinking that if the water coming out of the chiller is hot, that means that it pretty much has soaked up as much heat as possible. But, if the water is coming out cool, that means it maybe cooling the wort faster. My brain cannot wrap itself around this…so I am asking here because I get good answers.

 

[Willammes Macena]

Considere que o material utilizado para fazer o chiller tem papel fundamental na transferência do calor do mosto para a água!
Um chiller de cobre troca mais calor comparado a um de inox, com isso haverá uma diferença na temperatura da água na saída, ao usar o de inox você teria a sensação de que está saindo mais frio e no caso do cobre a percepção é que ela (água) é bem mais quente

Desculpe, minha língua inglesa é ruim

 

[Wagon_6]

I recall over the years the recommendation is to let it rip. Not a scientific answer but after using a Jaded Hydra IC with a ton of surface area, it really pulls out the heat quickly.

 

[Airborneguy]

You don’t have control over the temp of the water coming out. It’s physics.

Get it in there as cold as possible. It will come out much warmer as it picks up the heat from the wort. Exit water will gradually cool as the wort does.

 

[Architect-Dave]

You don’t have control over the temp of the water coming out. It’s physics.

Get it in there as cold as possible. It will come out much warmer as it picks up the heat from the wort. Exit water will gradually cool as the wort does.

This is true - and it has been over 30 years since getting a three week lesson in thermal dynamics in physics. And that is why I am curious. Well, I can control the speed of the water - or pressure - and slowing down the flow makes the water come out hot. Speeding up the flow makes the water come out cool. I am just trying to get a grip on the most efficient way…But, going forward, I got a second coil on my recent electric kit, so I will have one in a bucket of ice water to get that water coming into the actual cooling chiller as cold as possible And find a happy medium of flow to really get that cold water to pull off the heat of the wort.

 

[Airborneguy]

That’s what I do because I ended up with a second chiller. It definitely speeds the process up.

When I am using both, I slow down the flow rate to maximize the pickup from the “iced” chiller. When my ground water is cold enough, I just let it rip.

 

[odie]

I run mine sortta slow. If it's coming out too cold, then the water has not absorbed as much heat because the flow is too fast.

If the water is flowing too fast, it's taking less heat with it (per volume of water), but a greater volume of water is flowing thru during the same time period.

In reality, it probably doesn't matter that much, it just seems very wasteful to have the water on full blast. Going a bit slower allows for more heat absorption per gallon of water used.

If I had immediate use for all that water then I probably wouldn't care...

 

[scrap iron]

^^ this, What odie said. I run my water through the chiller at about half the speed of full on. I have a pump and use the whirlpool method which chills very fast. I feel the output of the chiller and adjust until it's coming out hot or warm. If ran too fast the heat does not have time to transfer to the chiller water. As the wort cools more the output is not as warm. When I get the temp down to around 100 degrees, I use a cooler with ice water and a fountain pump to chill the rest of the way down to pitch temps.

 

[day_trippr]

Basic thermodynamics claims the greater the temperature differential the more btus per volume are extracted.
The only rational interpretation is to run full blast...

Cheers!

 

[RM-MN]

Which do you want? Slow flow brings in cold water and lets it extract heat from the wort and it exits hot. This is more efficient for water used. Faster flow means the water remains cool throughout the chiller and exits cooler, thus extracting heat quicker. This is less water efficient but more efficient for time. Which is more valuable to you? If you live in the Colorado River Basin, run that water real slow. If you live in the land of 10,000 lakes and you need to get other things done.....

 

[scrap iron]

Basic thermodynamics claims the greater the temperature differential the more btus per volume are extracted.
The only rational interpretation is to run full blast...

Cheers!

That's true but a lot of people, myself included, are concerned with water conservation. I try to find a practical middle solution. I also save the chiller water in the mash tun to split between it and the BK for cleaning.

 

[hotbeer]

When using an immersion chiller to cool down your wort, is it more effective to have the water that is being ejected be hot or cool? I

Is more effective for what, chilling or saving water?

If you want to chill the wort the fastest possible and marginal gains are included, then let it flow as fast as you can. If water needs to be conserved, then go with a slower flow.

However I also believe that if we experimented with this, we'd find that the marginal gains from running at max water flow aren't worth the extra water used by a long shot. Even for the place where I live and water is cheap and plentiful.

 

[Broken Crow]

Due to spine and nerve issues, stirring is difficult for me, but early on when I had an IC I watched the water coming out on full blast, noticed it wasn't very hot but the moment I began stirring the wort around coil it began to vigourously steam... That was one of the reasons I turned my IC into a CFC, which cools to pitching temp in one pass with the water valve about 1/3 open.
But..while I still used the IC I saw for myself how big a difference circuatiing to achive surface contact made.

 

[SanPancho]

if you have a copper chiller, your exit water temp should be about 10F-ish higher lower than your wort temp. more than that and you're "wasting" water, theoretically.

for a stainless chiller it'd be a bit higher, since its less efficient at thermal transfer, but i dont have an exact number for you. maybe 15 or 20?

so its really about your water situation. if you're trying to conserve water, monitor and adjust as necessary by slowing the water flow as the wort cools. i'll usually check every 10mins or while i'm cleaning. not a big deal.

if you dont care about conserving water then you can set it at pretty much full blast and let her rip. but by the time you've cooled about halfway, you'll really be wasting alot of water.

at the end of the day, its a question of whether you want to "waste" water or not, and that's a choice of speed(time) vs saving/wasting water(volume).

 

[tld6008]

I use 2 coils, one in as ice water bath and one in the wort. I run mine very slow and collect the spent water in 5 gal buckets. It takes about 12 minutes to fill one and after 3 are filled the wort temp is < 90f. The discharge water is as hot as the wort and if it feels cooler I need to either stir the wort or move the wort coil around to equalize the temp in the wort. I do this to the minimize the amount of water used. My coils are not as efficient as they should be but they work.

 

[balrog]

I flow AFAPossible until I have my 3 buckets of cleaning water. THen switch to recirculating with pond pump in cooler of ice. On cold days, getting to 60F for 5.5gal with 25 foot 3/8 copper chiller takes maybe half of the 16# bag of ice. In summer, I have to add the freezer icemaker bin to the cooler.

 

[VikeMan]

That’s what I do because I ended up with a second chiller. It definitely speeds the process up.

I have experimented with a second chiller as a pre-chiller, i.e. the pre-chiller sits in an ice bath. And it's better than no pre-chiller, but a more efficient and effective way to do it is to use a pond pump to recirculate ice water through a single chiller. i.e. chill as normal until the temperature drop slows down significantly, then switch to recirculating ice water.

Edit: Re-reading more carefully, I see this has already been mentioned a couple times.

 

[Airborneguy]

I’m considering that method. Maybe in the summer. Right now I’m taking advantage of the fact that I have cold ground water but can still turn my outside hose on for brewing because temps are above normal this winter.

 

[doug293cz]

The most efficient use of chilling water is when the cooling water exiting the chiller is as close as possible to the temp of the wort being chilled. If the chilling water comes out at the same temp as the wort, then you have gotten the maximum amount of heat removal per unit of water that was possible.

Usually cooling rate with an immersion chiller is limited by how fast heat transfers from the wort to the water in the chiller. You would think that the most important variable here is the thermal conductivity of the chiller material, but this is not the case. What limits in most cases is the thermal gradient between the bulk of the wort, across the wort adjacent to the chiller coils. The best thing you can do to improve the rate of heat removal is agitate the wort or chiller. If the wort is still, then you set up a fairly gradual thermal gradient, which slows heat transfer from the wort to the cooling water. If the wort, or chiller, is agitated, then the gradual gradient is destroyed, and you get hotter wort in contact with the chiller, which speeds up thermal transfer. Once you have the wort moving swiftly enough relative to the chiller coils, then the material of the chiller becomes the limiting factor.

I know when I use my chiller, if I agitate the chiller, the exit water stays hot, but if I just let the chiller sit there, the exit water quickly cools down, even tho the wort is still hot.

Brew on

 

[balrog]

I remember long ago someone had a "Wasp" named chiller and they showed time lapse recirculating through first 5gal of water, then another 5gal but dumping in contents of std fridge ice maker and recirculating. Within I think 15-20m it was down to 70F, IIRC.

But what stuck with me about the video and method was (A) a beer was consumed during chilling, which I thought was a just a capital idea; and (2) that guy held the copper chiller and moved that thing like a drunken salsa dancer whose hair was on fire. Okay, maybe not like that, but a LOT.

Ever since then, I stand at my BK and agitate the bejeeber with my immersion coil and I can chill to 60F in 12-18 minutes. No beer though. I found out I should wait on the beer.

No salsa dancing either. I've got the wrong shoes for it.

 

[Broken Crow]

No salsa dancing either. I've got the wrong shoes for it

Just take off your shoes and play some Tito Puente while 'stirring'!

 

[k-daddy]

if you have a copper chiller, your exit water temp should be about 10F-ish higher than your wort temp. more than that and you're "wasting" water, theoretically.

for a stainless chiller it'd be a bit higher, since its less efficient at thermal transfer, but i dont have an exact number for you. maybe 15 or 20?

so its really about your water situation. if you're trying to conserve water, monitor and adjust as necessary by slowing the water flow as the wort cools. i'll usually check every 10mins or while i'm cleaning. not a big deal.

if you dont care about conserving water then you can set it at pretty much full blast and let her rip. but by the time you've cooled about halfway, you'll really be wasting alot of water.

at the end of the day, its a question of whether you want to "waste" water or not, and that's a choice of speed(time) vs saving/wasting water(volume).

I think you mean the exit water should be 10F-ish "lower" than the wort temperature.

 

[SanPancho]

I think you mean the exit water should be 10F-ish "lower" than the wort temperature.

yep, corrected.

 

[bike2brew]

I have experimented with a second chiller as a pre-chiller, i.e. the pre-chiller sits in an ice bath. And it's better than no pre-chiller, but a more efficient and effective way to do it is to use a pond pump to recirculate ice water through a single chiller. i.e. chill as normal until the temperature drop slows down significantly, then switch to recirculating ice water.

Edit: Re-reading more carefully, I see this has already been mentioned a couple times.

Here's my setup. Its an upgrade from my previous effort. The ice bath is pumped and recirculating through the chiller with an inexpensive submersible pump. The water is still cold and used to fill my swamp cooler for the fermenter. Works great and saves a lot of waste down the drain.

 

[Nixter]

Reducing the flow through the chiller will give one nice hot washing up water.
A second chiller immersed in an ice bath works pretty well right up to the point where the temp of the wort equalizes with the ice bath water around a temp that always seems a little above the maximum pitching temperature. At that point break out ice cubes and your Dilution/ Boil-off Gravity Calculator.https://www.brewersfriend.com/dilution-and-boiloff-gravity-calculator/

 

[Teufelhunde]

This is true - and it has been over 30 years since getting a three week lesson in thermal dynamics in physics. And that is why I am curious. Well, I can control the speed of the water - or pressure - and slowing down the flow makes the water come out hot. Speeding up the flow makes the water come out cool. I am just trying to get a grip on the most efficient way…But, going forward, I got a second coil on my recent electric kit, so I will have one in a bucket of ice water to get that water coming into the actual cooling chiller as cold as possible And find a happy medium of flow to really get that cold water to pull off the heat of the wort.

Speed up the flow, you will be cooling better, but you will also be wasting a lot of water (very important to those of use in the Southwest).....

 

[Architect-Dave]

Here's my setup. Its an upgrade from my previous effort. The ice bath is pumped and recirculating through the chiller with an inexpensive submersible pump. The water is still cold and used to fill my swamp cooler for the fermenter. Works great and saves a lot of waste down the drain.View attachment 810330

Yep! I have two chillers and am planning on doing an ice bath for the first chiller

 

[hotbeer]

Yep! I have two chillers and am planning on doing an ice bath for the first chiller

I did that once. It helped some but not as much as I was hoping for. Just pumping the ice water from the bath through the chiller in the wort seems much more effective to me.