Possible a dumb wort chiller question

[MikefromMichigan]

I recently made a copper immersion wort chiller out of a 25 ft roll of 3/8 copper tubing. It works great, cooling my wort from boiling to under 80 deg in less than 15 minutes. I have used it 3 times, so I now have a question and an observation.

Does it matter if the water enters in from the top and flows down or if it should enter from the bottom and flow up, or does it make a difference?

When I first used the wort chiller I expected the water to exit considerably warmer than when it entered, and it was. As the wort cooled so did the water exiting the chiller, again as expected.

The last 2 times I used it the water exited a lot cooler than I expected, not much warmer than my faucet temperature, which surprised me, but it still cooled the wort in under 15 minutes. My faucet water is approx 70 deg. Any suggestions why my exit water was not warmer?

 

[AgentHubcap]

Did you have it turned up more? The faster it flows though, the less it will heat up the water in the coils (but it still cools well)

 

[Phunhog]

I don't think it really matters but....I believe it might be a tad bit more efficient if the the cooling water enters from the top. Heat rises so your hottest wort will be at the top of your kettle in theory.

 

[helibrewer]

I have my cooling water flow from bottom, up....not sure why, not sure it matters

 

[Aschecte]

It kinda matters because you have what's called friction losses and gains by pushing the water up it creates friction as well as gravity works against you and therefore the water actually will not cool as quickly and will not carry away the absorbed heat as fast either. All that said its not a huge difference but there is a difference none the less.

 

[helibrewer]

It kinda matters because you have what's called friction losses and gains by pushing the water up it creates friction as well as gravity works against you and therefore the water actually will not cool as quickly and will not carry away the absorbed heat as fast either. All that said its not a huge difference but there is a difference none the less.

Maybe, but I do use a pump to circulate the wort during IC use so I'm gaining efficiencies there and eliminating stratification.

EDIT: This is from John Palmer's Book, "How To Brew", p. 284:

The cold water “in” fitting should connect to the top coil, and the hot water “out” should be coming from the bottom coil for best chilling performance.

So maybe I'll switch mine up....

 

[MikefromMichigan]

Thanks for the replies. I will use the top filling for the " in", in the future. I also do not have the faucet turned on full, so I will experiment with that next time I brew.

 

[ArcLight]

I've never seen an immersion chiller that has a top and bottom. Both the inlet and outlet are at the top and level with each other.
Might you have pictures?

 

[IFMracin]

I've never seen an immersion chiller that has a top and bottom. Both the inlet and outlet are at the top and level with each other.
Might you have pictures?

No, both pipes are at the same location, but one feeds to the top of the coil, and the other comes from the bottom of the coil.

 

[ArcLight]

>>No, both pipes are at the same location, but one feeds to the top of the coil, and the other comes from the bottom of the coil.

OK, yes, now I understand. Doh!