Immersion Chillers, full throttle or trickle?
 

I just made an IC, and am doing my test run/cleanse with a pot of boiling water. It is a 20' copper loop (3/8" inside dia. tube), and I have a pre-chiller but am not going to use it until I do a real batch.

My question is, when people use their IC's do they open the faucet/hose up full throttle, or do they let it trickle through?

The reason I ask is that I was forced to tone done the water pressure because I need to snug up my connection to the faucet (it sprays everywhere if I open it up full-bore), but the water coming out of the chiller is still only about 80-90*, while the pot-water is still around 120* (My input water is around 55*).

If I had it running wide open, presumably it would come out even colder right? Since the water would travel through the chiller faster, it wouldn't have enough time to exchange the heat is what I am thinking.

I don't want to just waste water if I don't have to, I am guessing it would cool marginally faster since the water in the coil would be getting replaced faster with cold water...but I don't know if it is worth the wasted gallons of water.

Has anyone ever experimented with this or have any good rules of thumb?

:tank:

Right - if it goes through faster, the output will be colder. It will chill faster that way, but be less efficient.

Make sure you're moving the chiller around in the wort - that will drastically increase your efficiency and reduce chilling time. I usually run mine about halfway open and it chills in under 5 mins.

I made a 1/2" IC and the trickle method works best. Some searching showed that you want the water exiting the IC to be only a few degrees colder than wort temperature for efficiency.

NO.

faster is NOT always better. you need to give the water flowing through the chiller time to pick up the heat from the wort.

I have a 25' 3/8" homemade chiller and find its best to start out fast, but slow the flow as the temp comes down.

Cool, sounds like trickle-to-medium is the general consensus. I'll stick with that, and I think once I get my pre-chiller in the loop with some ice-cold water it will probably chill it so fast (compared to my old pot-in-the-sink method) that I won't feel any need to increase the flow rate.

Thanks HBT!:tank:

I'm not a Scientist nor do I play one on TV, but I have heard there is a change in efficiency of the heat transfer In relation to the temperature difference between the hot and the cold.

In essence, the closer the temp of the wort gets to the temp of the tap water, the less efficient the transfer of heat becomes.

All I do is adjust the flow so the water coming out of the chiller is warm.

I go full blast and the faster I go the faster it cools down.

Wrong.

Faster is ALWAYS better in an IC.

It's basic thermodynamics. Running the water faster means the IC coil will stay cooler, and heat will move exponentially faster into a cooler object.

You might conserve some water by running it more slowly.

I have to agree. The greater the differential between the amount of heat in the coil versus in the wort, the greater the transfer. Heat, pressure, concentration of matter, all move passively from high to low. If the water inside the tubes becomes warmer, the closer you get to equilibrium and no net movement. That's why the counter current method works so well.

Same goes for me. The faster the cold water moves through there the faster the wort cools down. I've tried not wasting as much water (slower flow) and it just meant for a longer time to chill the wort.