Debating an immersion cooler

Freinds, I am in a sort of quandry. I need a way to cool wort from boiling to pitching temps. I have been looking at several immersion chillers and there are two that stand out above the rest. One is 1/4 diameter by 25 feet and the other is 3/8ths by 25 feet. Since the largest batch I plan on ever doing will be 5 gallons would the smaller diameter chiller be too small. What would the difference in chill time be approxamately? If the time is reasonably the same or close enough could any one see the additional expense involved with the larger diameter tubing. The larger unit has soldered fittings for a garden hose already attatched, the 1/4 has about 12 feet of hose included with a fitting to connect a garden hose also. The major difference is the soldered fittings versus the use of hose clamps. In the future I could repurpose the small unit to rest in a chilled/ice water bath and pump the cooled water into a second chiller in the mash tun too. So I have a decision to make and need a little input from experienced brewers on this issue.
Bob

Have you considered a Plate Chiller? Both of the guys I brew with here and there have 25 foot copper immersion chillers, and while they work just fine, I've never been impressed.

Before I got my plate chiller, I would transfer my wort to a aluminum bucket and do an ice bath in my sink. With 28 lbs of ice, I could go from 200F+ to 80F in 18 minutes. Both of my IC buddies took about 25-30 minutes with 78 degree ground water (we're in central FL).

Anyway, with my new plate chiller and the same 78 degree ground water, I can get a 5 gallon batch down from 200 to about 85 in around 14 minutes. That's just with ground water. I could do it faster and chill it more by sending colder water through with a small sump pump, which I need to move on one of these days soon.

Anyway, both my buddies with the 25 ft ICs now have pre-chillers on their wishlist because I've shown them that their current process with a single chiller is pretty slow.

I have the 30 plate chiller if you wanna check em out. A 40 or 50 plate would work even faster:

http://www.dudadiesel.com/heat_exchangers.php

The larger the diameter the more surface area there is and the faster it'll cool. I made my own out of 20 feet of 1/4in diameter copper tubing for about $25 and it cools down to pitching temp in about 15-20 minutes (ground temp is near freezing here in PA though). My advice is if you're handy then build one. If not then buy either one. The difference in chill time will probly only be a minute or so.

I have a 20 foot, 3/8" diameter immersion chiller, and it takes me about 15 minutes to get from boiling to 70 degrees (I have learned that placing the exaust tube in such a way that it runs against the outside of the pot speeds things up a bit). I love this thing.

I'd personally go for the 3/8 if it were me.

I have a few chillers, what I have learned both by post on this forum and experiencing the results first hand. It is that surface area is the top of the list when considering on investing in a device to cool your wort ASAP.

Given the same water temp supplied to both chiller models it comes down to physics, the one with more surface area will cool the same volume of liquid at the same temp more efficiently.

The reason I have multitude chillers is I had planed to do the same thing you alluded to in your post. I found that a $20 pond pump from Harbor Freight,a Rubbermaid tote and a couple of 2.5 gallon square water jugs of ice I make in my chest freezer worked far better that the two chiller setup.

Last summer I chilled 6 Gallons of wort to 68 degrees in 20-25 minutes with a 30 ft. 1/2 in copper chiller. When I did this test I used the ground water @ 74 deg. to cool until the wort reached 100 deg. then I switched over to 34 deg. ice water.

My suggestion to you would be buy big. Even if you don't plan on ever brewing over 5 gallons get the largest chiller that will fit your brew pot and will be covered by wort when immersed in your pot.

If you can get your hands on the Jan. issue of Zymurgy, it has an article explaining a test that they conducted using 1/4" and 3/8" chillers. The length of each was 22' of copper. The result was that the 3/8" chiller dropped the wort to 80* in 21 minutes while the 1/4" chiller took 30 minutes. These results were both achieved with no agitation.
The reason was basically that the outflow from the hose was 2.5 gpm. The outflow through the 3/8" chiller kept the 2.5 gpm rate while the output of the smaller chiller was reduced to 1.5 gpm. This was the difference and the reason it took 9 minutes longer.

The 3 keys of the article was:
1. Maximize the water flow rate through the chiller
2. Minimize the water temp.
3. Maximize the chiller surface area

If I was you, I'd build a 20' 5/8" OD chiller if possible, keep the flow wide open
and use agitation. That would be the fastest way to chill while using the least amount of water.

What a 1/2" x 50' IC and a whirlpool I can be under 70 in about 8 minutes last time I timed it.. Whirlpooling makes a BIG difference...

I have the 25 ft 3/8 with soldered fittings and it is great for 5 gallon batches. Not having to deal with clamps plus the extra surface area makes that the one you should get between the 2 you listed. It was around 42.00 if I recall, and well worth it.

I circulate (whirlpool) using my diaphragm pump along with a 3/8" SS IC and things cool down in about 10 minutes, then I pump from the kettle though a 20 micron filter into the fermentor.

Well I notice you are in Florida - if it's anything like Texas your tap water should get into the 70°-80° range so you'll definitely need either a pre-chiller or a reservoir to chill in. I'd engineer this now instead of a few months from now.

I'd go with the 3/8 inch tube - I run 3/8th and I get nearly 100% heat exchange over 50ft even while using 40° water - I regret not splurging for the 1/2 in so bigger is better in this situation.

I would also suggest making your own. It's insanely easy, and all you need in terms of tools is a paint can and a rubber mallet.

Just this past weekend I made a 50ft 1/2 inch immersion cooler (see youtube for diy wort chiller videos), using pretty chilly cleveland ground water. I got my 5.5 gallons from 200 to 70 in about 9 minutes (whirpooling of course). May have spent about $70 total (I had to grab a couple extra fittings so I could attach it to my kitchen sink) but it worked very quickly compared to the 1/4 inch one I had used 2 weeks earlier and was very pleased with the results.

rhamilton said:

Well I notice you are in Florida - if it's anything like Texas your tap water should get into the 70°-80° range so you'll definitely need either a pre-chiller or a reservoir to chill in. I'd engineer this now instead of a few months from now.

I'd go with the 1/4 inch tube - I run 3/8th and I get nearly 100% heat exchange over 50ft even while using 40° water - I regret not splurging for the 1/4 in.

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Do you mean you regret not slurging for 1/2 inch? 1/4 inch is smaller than 3/8.

brewit2it said:

Do you mean you regret not slurging for 1/2 inch? 1/4 inch is smaller than 3/8.

Click to expand...

Math fail. Regret doing 3/8 instead of 1/2 -- so for the OP 1/4in should be out of the question.

helibrewer said:

I circulate (whirlpool) using my diaphragm pump along with a 3/8" SS IC and things cool down in about 10 minutes, then I pump from the kettle though a 20 micron filter into the fermentor.

Click to expand...

Don't want to hijack this thread but curious about your filter.. can you give me a link to what you're using? Also, do you use whole/pellets? Hop bag?
thanks!

Thank you all for the input. Ordered a 3/8ths by 25 foot stainless chiller this AM. Hope to have it in time for a brew session either this weekend or next. Slowly but surely I am getting closer to doing AG 5 gallon batches. Thanks for all the help and inspiration.
Bob

Rbeckett said:

Thank you all for the input. Ordered a 3/8ths by 25 foot stainless chiller this AM. Hope to have it in time for a brew session either this weekend or next. Slowly but surely I am getting closer to doing AG 5 gallon batches. Thanks for all the help and inspiration.
Bob

Click to expand...

What made you go the stainless route?

Actually the price versus the 25 foot copper plus shipping was less. I looked at several in the 50 or so dollar price range, but the wanted stupid money to ship it. I found this dealer who only wanted 44 bucks for the coil and 10 bucks to ship it from Upstate New York. So the total was around 55 buck and the coppers were ranging nearly 60. It doesnt really make any sense but I would rather have a more durable and easily cleaned item if I can get it for about the same or little more money. I figure this will last forever and if I go to HERM or RIMS I could even run wort on the inside or outside. So I popped for the cash this morning and got one step closer to AG brewing. Mash tun and conversion are next while I fabricate a stand to do it all on. I'm a retired welder so I can do the stand standing on my head asleep when the time comes. Thanks for asking though.
Bob

Built my own out of 50feet of 1/2" tubing. A good amount of coils are above the level.of my wort but if I ever upgrade and do larger batches ill be set. Tap water here in NYC in the winter is about 50degrees and it cooled my batch down in under 10minutes. Absolutely awesome.