Closed Circuit Cooling Calculator - ice water recirculation, how much do I need?

So this has been discussed around here quite a bit, and I finally got off my ass and made a little spreadsheet that will make life easy for everyone.

It is attached...

Basically, you need to fill in any yellow areas, batch info, ice amount, water temp, etc. and the sheet will tell you your equilibrium temps. It assumes no losses so it won't be 100% real world, but it will be a good ballpark guess.

Cheers!

Justin

View attachment Closed_Circuit_Cooling.zip

Updated: Now includes a spot to enter wort temperature. This allows you to calculate how much ice you will need if you knock a couple degrees off initially with just hose temps.

For example, you can circulate ice water but catch the first runnings in a bucket or you MLT initially until your wort is at 150º then return the hot water to the ice bucket for finishing the cool.

I hope that makes sense.

View attachment Closed_Circuit_Cooling.zip

Thanks BK this is very helpful. Chilling 12 gallons is going to take alot of ice, but having a deep freeze right next to my rig is also very helpful I can do 40 lbs of ice, then afterwards just re-freeze it all.
On my first brew on my system the temp dropped SO fast at first, I'll just have to refine my strategy of when to start recirculating (I foolishly tried to recirc right off the bat).

It isn't foolish. I did a bad job of describing the process in the beginning of the DITCHES I thread. I revised it later, but that thread got very long.

The heat exchange system on DITCHES is crazy overpowering, just the way we like it.

Granted, I know you can use enough ice , dumping the "hot" coolant back into the ice reservoir and still come out with cold wort. My argument is that collecting the output water for the first 3 minutes is more efficient use of ice because you're ejecting a large amount of heat at that time.

True. With my current system (Simple / 2P-Twent-E), it is just way too easy to fill up the MLT with 20# bag plus the ice from my freezer and cool down. No hoses or anything. It is just soooo easy.

For 4 gallons of wort, 5g of 55º water and 23# of ice gets me to 67º in about 12 minutes (IME). It is the nicest system I have ever cooled with by far.

With larger batches, as described above, the amount of ice needed becomes prohibitive. I don't have access in the summer to 60# of ice. Now in the winter....

Or, if like Budzu, you have a chest freezer with extra space... 60# of ice will cost you about $0.50 at current energy rates, so that may be an awesome option.

For example, a five gallon bucket will give you ~38# of ice. That may not be a usable shape though...

I just use the warm output water for watering plants and the yard. I use the hose water for the first few minutes, to get that high heat out, then switch to the pump in the cooler full of ice water.

The plants get a drink, and the wort gets cooled.

Not really an option for apartment dwellers, I know. How fast does the hot return water eat up your ice?

I would say quickly. The whole system is cooled down within 12ish minutes, so everything transfers quickly. That is with a 20' copper immersion coil and a stirrer.