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Old 09-14-2011, 03:38 AM   #1
ImperialStout
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Apr 2011
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Just got thru cooling 5 gal wort. Took 1/2 hr to drop temp from 134 deg F to 70 deg F for pitching yeast and had to use ice bath.

My cooler is 20 feet of copper tubing, 5/8" OD / 1/2" ID. Many commercial immersion coolers are 3/8" x 25 feet. Don't know if the 3/8" is OD or ID.

To save money I bought the above larger diameter but shorter copper tubing figuring the cooling ability would be about the same.

The tubing has 6 coils, 8" in diameter and 6.5" tall. I plan to separate the coils to 12" tall to increase surface area contact (I think) with the wort. Can not change diameter as copper will kink.

Questions: Is a 1/2 hr an expected time to drop temp 64 deg? Some post much faster temp drop times.

 
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Old 09-14-2011, 03:42 AM   #2
sudsmcgee
 
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That's pretty good for 20 feet. Unfortunately the coil length is the single biggest factor after water temp. My chiller is 40' and I can chill the wort to 60' in the winter in about 15-20 min.
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Old 09-14-2011, 03:49 AM   #3
Boerderij_Kabouter
 
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Temperature differential between the wort in contact with the chiller and surface area are the largest factors. The temp of your ground water is going to be whatever it is and you can't control that unless you use an ice water recirc system.

The 5/8" tubing will make for a quicker heat exchange than would a 3/8 tube.

The biggest impact you can make will be to swirl the chiller through the wort or circulate the wort around the chiller. Natural convection is rather inefficient and is a major reason for how long it took to cool your wort. Stirring around the chiller, or stirring with the chiller itself will greatly speed the time.

You should be able to drop that time to around 20 minutes depending on your ground water temp.

 
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Old 09-14-2011, 03:53 AM   #4
phoenixs4r
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Jun 2011
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You need to move the wort around for immersion chillers to be efficient. I had to redo how I cooled my worth since I had to move from draining in the kitchen to draining my chiller in a pond. My hose was 2 feet short so I had to hold it and shoot it into my pond (lol). As crappy as that was, you could really feel the temperature of the waste water rise when my swmbo stirred it (insert inappropriate joke here)

 
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Old 09-14-2011, 04:13 AM   #5
ImperialStout
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Apr 2011
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Stirring seems to be the answer. I didn't stir at all for the first 20 min and temp went down very slowly. Stirred last 10 min and temp drop improved. Will separate coils, put in ice bath and stir from the beginning in the next batch. Hopefully wort will cool to 70F in 20 min.

Thanks

 
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Old 09-14-2011, 05:12 AM   #6
GodsStepBrother
 
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, Texas
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I live in El Paso Texas and made a pre chiller. I would freeze this pre chiller over night in a bucket full of water, however I always had problems with cooling the beer down fast. What helped out the most was adding rock salt to the pre chiller, but still not very effective.

As other has said stirring is key to cooling down fast. Also 'especially' if a pre chiller is being used turn the water pressure down so the water passes slower through the colder chiller and has a chance to cool before going to the chiller in the wort. I finally gave up on this and ended up making a new chiller with 1/2 inch copper pipe so i could get more surface area. I also invested on a pump and I can now circulate ice water through the chiller. This has worked the best and I no longer have any problems cooling wort when it is 100 degrees F outside.

 
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Old 09-14-2011, 07:47 AM   #7
Coolmac
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May 2011
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If you want to drive home just how important stirring/agitation is, feel the temperature of the water coming out of the cooler after a few minutes of not stirring. Then stir and feel the water again.

 
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Old 09-14-2011, 11:16 AM   #8
pcollins
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Mar 2010
Cambridge, ON
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Yeah, stirring is pretty key. I'm only down to 30 minutes chilling a 5g batch in my kitchen. That's about as well as I can do.

Separating your coils I don't think will do much. It won't increase the surface area because the coils are still the same size.

Try messing with your flow rate of the water as well. I was going quite slowly at first and it was taking a long time. When I finally opened it right up it definitely helped.

 
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Old 09-14-2011, 11:20 AM   #9
Northcalais40
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Jul 2010
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Another option, which I use, is to put your chiller in an Ice bath and run your boiled wort through it. It requires good sanitation, but you can boil it in the wort the same way you would normally.

I can chill to cold in the time it takes to drain the kettle. I end up using about 3-4 bags of ice (natural ice and snow in the winter)

 
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Old 09-14-2011, 11:51 AM   #10
pcollins
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@Northcalais40: I have a friend who does this as well. It is VERY effective.

 
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