IC questions

HollisBT · 10-10-2011, 09:33 PM

So after a little bit of thought and consideration, I have decided to ditch my idea of using a plate chiller, and have decided to go with an immersion chiller for my brew system. And after a bit of shopping around online, I have decided to try and make one, but I have a few brief questions about materials to use.

Does the copper tubing diameter have a significant difference? I can get 50' of 1/4" tubing for a good bit less than I can get 3/8" tubing. I know that the smaller tubing would have less surface area, but would this make a significant difference in performance?

Also, how long does the chiller need to be? Is 20' of copper tubing long enough? Or should I go with the 50' coil? OR, should I go with the 50' coil cut in half and make a two stage chiller with a pre-chiller for better performance?

Any input here would be greatly appreciated

**OneHoppyGuy** · 10-10-2011, 09:42 PM

Larger surface area = more effectiveness
you want at least 3/8" preferably 1/2"
What size kettle (how much) are you trying to chill?

HollisBT · 10-10-2011, 09:48 PM

I am making a kettle out of a half barrel keg, going to be doing 5 gallon batches for right now, possibly 10 gallon in the future.

krduckman · 10-10-2011, 09:52 PM

Quote:

Originally Posted by HollisBT

So after a little bit of thought and consideration, I have decided to ditch my idea of using a plate chiller, and have decided to go with an immersion chiller for my brew system. And after a bit of shopping around online, I have decided to try and make one, but I have a few brief questions about materials to use.

Does the copper tubing diameter have a significant difference? I can get 50' of 1/4" tubing for a good bit less than I can get 3/8" tubing. I know that the smaller tubing would have less surface area, but would this make a significant difference in performance?

Also, how long does the chiller need to be? Is 20' of copper tubing long enough? Or should I go with the 50' coil? OR, should I go with the 50' coil cut in half and make a two stage chiller with a pre-chiller for better performance?

Any input here would be greatly appreciated

My 25' 3/8 in. works fine for a 5 gallon batch.

**JohnnyO** · 10-10-2011, 10:06 PM

Agree with above. You need to use at least 3/8" diameter tubing. The 1/4" tubing restricts the flow of the water too much so that it effects efficiency greatly. I use a half barrel for my boil. I use a 50' immersion chiller that has 1/2" diameter tubing. I got mine from morebeer.com. They sell a recirculating arm that aids in the chilling. I picked that up too and it has been doing an excellent job on my 10 gallon batches. You should definitely make/buy a 50' chiller if you ever plan on doing 10 gallon batches.

HollisBT · 10-10-2011, 10:34 PM

Alright, guess I will stick with the 3/8" copper tubing, I was just looking to save a little bit of cash, but might as well do things right

.

What would be the recomended length for the chiller? Is using a pre-chiller going to be that much more efficient compared to having more length in the kettle? FWIW I will likely be connecting this to my kitchen sink, and using a length of plastic tubing to reach outside. Or I might spend the money for a submersible fountain pump and I could recirculate ice water from my mash tun through the chiller...

subliminalurge · 10-10-2011, 11:10 PM

Quote:

Originally Posted by OneHoppyGuy

Larger surface area = more effectiveness

Don't forget that the larger tubing also puts a larger volume of cooling water into the wort at one time. This works hand in hand with the larger surface area by providing more water to absorb more heat.

With a 1/4" tube you could easily have the cooling water heated to the same temp as the wort within the first few feet, negating the benefit of the rest of the tubing. Of course, as the wort cools down, more and more of that length will become useful.

Just saying that bigger is better for several reasons, not "just" surface area.

HollisBT · 10-10-2011, 11:58 PM

Excellent point, I hadn't thought about it that way. Is it worth it to consider 1/2" tubing? I have read that it is much harder to bend though... And price wise I would imagine that I would only buy 25' of it as compared to 50' of the 3/8". I can't imagine that the extra 1/8" would make that much of a noticeable difference though.

subliminalurge · 10-11-2011, 12:09 AM

Given the price difference, I would be inclined to go with 50' of 3/8".

The speed at which the heat transfers depends on the difference in temp between the wort and the cooling water. At the end of cooling when the wort is getting close to pitching temps that extra length will really help those last few degrees go faster.

I haven't done the math, but I'm reasonbly comfortable making the statement that 50' of 3/8" is going to have both larger surface area and larger internal volume than 25' of 1/2". I'm not really in a "math mood", so if that's incorrect I'll leave it for someone else to call me out on it.

**Golddiggie** · 10-11-2011, 12:23 AM

I have to ask, why did you decide to not go with a plate chiller?? With the IC, you need to move the wort around it, or it in the wort, to get decent chill times. With a plate chiller, you don't have that issue. If you just leave the chiller sitting there with water running through it, it won't chill nearly as well/fast. Unlike a plate chiller or CFC.

For reference, my brew buddy is using a ~20' 3/8" copper IC (I made it) to chill about 5 gallons of boiling wort to pitching temps. This past Friday, his chill time was about 30 minutes (with actively moving the IC in the kettle). Using the same water source (I actually use the hose faucet, he uses the kitchen sink/faucet) I was able to get to about 62F in under 15 minutes (closer to 12)... I recirculated through the plate chiller (Rebel Brewer ChillHog 4000 40 plate chiller) to sanitize about 5 minutes before flame-off. We then started the chilling water feed, and I recirculated into the kettle for about 5-8 minutes before changing over to feed the fermenter (without the pump). The ball valves in the kettle and on the chiller were wide open the entire time. I was able to get the wort from boil to ~70F in the ~8 minutes it was recirculating.

A side benefit of using a plate chiller (as well as CFC) is that you get to leave the lid ON the kettle while you chill. Zero chance of anything falling into the wort as it cools that way. Even with recirculating, the opening in the lid is minimal. I'll probably end up installing a fitting in my kettle so that I can keep the lid fully closed while recirculating/chilling.

For the record, my absolute best time to chill 5 gallons of boiling hot wort to ~66F was about 10 minutes, WITH a 50' 3/8" IC, in the winter. For some reason, the 50' 3/8" copper tubing sold at Lowe's is thicker wall than the 20' section, so it's much harder to bend/form. I wouldn't even think about trying that again unless I had machinery to do it.

I've also added QD's to my plate chiller setup. I have two [female]on the wort side, with a male on the RebelSmart where it goes into the chiller, and a female on the ball valve output side. This allows me to turn the valve assembly as needed, as well as remove it when back-flushing the chiller. It doesn't take much to get fittings to make things much easier on you...