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HERMS heat exchanger as wort chiller?

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blacks4

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[EDITED]

I searched the forum and Google and didn't find too much info. What about using the HERMS heat exchanger to cool the wort also (by pumping the wort through the heat exchanger)? it's just a reverse IC and as long as you're circulating the ice water in the HLT, why wouldn't this work great (say instead of a plate or CF chiller)? The only other issue I see is I wanted everything all stainless but copper conducts heat much better.

Just curious if more of you are doing it and/or if there are specific reasons not to.

Thanks guys.

Steve
 
I use the 50' stainless 1/2" immersion chiller from Midwest as a HERMS coil in the HLT and as a post chiller submerged in ice water in my old 10 gallon rubbermaid. To chill after the boil, I pump through a hose water chilled plate chiller first, then through the coil and get as low as 40F in the winter in one pass at full flow with a center inlet March. Since the plate chiller, coil and hoses hold so much wort (almost a half gallon), I purge them into the fermenter with CO2.
 
I initially did that with my HERMS. The problem was that it took 42 pounds of ice to chill 5 gallons of wort from boiling to 68 degrees. I wanted a HERMS and a pump to avoid lifting, and here I was lifting more than ever!

If you have a cheap/easy source of ice then it should be no problem for you! I decided to go with a CFC instead, and it works well for me.
 
Yeah, even with the double chiller set-up I have, it uses 40 lbs of ice to get 11.5 gallons into the fermenter at 40F.
 
that doesn't sound too bad then for me (Yooper & dstar26t) because I live around the corner from an ice store and 35# bags are $7. I'd rather add $7 to the cost of 10-11 gallons then use 40-60 gallons of hose water. Thanks guys.
 
If you check out my build:

https://www.homebrewtalk.com/f170/mash-tun-5-gal-electric-brewery-266056/

I have done something similar to what you're thinking. I am using a counterflow heat exchanger as both a heater and a cooler. During mash the HLT water is pumped around the shell side of the coil, with the wort on the tube side. During cooling, hose water runs through the shell side, and wort through the tube side. The exchanger is plumbed so that the return always goes to the HLT. If I need to, I can fill it with ice and pump ice water through the shell side.

There are pro's and cons to everything, with this arrangement you need 2 pumps, but don't have to worry about stirring or agitating the HLT. One of the most significant factors in heat transfer is a thing called film coefficient, a lot goes into it, but what it comes down to is, the more turbulent (fast) the flow is on the inside and outside of the tube that is conducting heat, the better. This arrangement has that advantage over a traditional HERMS coil, because in that case the water on the outside is virtually still, even with an agitation system, the flow inside the HLT will never be 'turbulent'.

The other way I look at it is, if you have a CF heat exchanger, why build another less efficient heat exchanger, when you can just use one for both purposes. Really it comes down to 6 vs. 2-3's, both are going to work, and clearly do, it's just a matter of how YOU want to do it. Hope this helps.
 
I use the 50' stainless 1/2" immersion chiller from Midwest as a HERMS coil in the HLT and as a post chiller submerged in ice water in my old 10 gallon rubbermaid. To chill after the boil, I pump through a hose water chilled plate chiller first, then through the coil and get as low as 40F in the winter in one pass at full flow with a center inlet March. Since the plate chiller, coil and hoses hold so much wort (almost a half gallon), I purge them into the fermenter with CO2.

So you just have that IC completely intact and move it around as needed? Did you ever think about cutting and permanently installing it into the HLT with compression fittings? I'm looking at that Midwest IC also, but mainly because it's a pretty tight SS coil that will fit in a keggle.
 


I did think about that and I like to be able to remove it to use it as the post chiller in my rubbermaid cooler full of ice water. I have a fully modular system so by the time chilling comes around, the HLT and it's burner are clean and stored. The cooler doesn't need cleaning so it saves time at the end of the day.
 
Here's a pic from brewing yesterday showing the IC as part of the chilling set-up.

 

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