Interesting Chiller Idea

[pixelpixi]

One of my friends at work had an interesting idea for cooling an aquarium: just run cold tap water through a coil in the tank.

I just measured cold water coming out of my faucet and it's about 60 degrees. That means that in theory, I could bring the temperature of my 100 gallon system down from 80 to 75 by running 50 gallons of tap water.

After the water goes through the coil and takes up the heat it could go through RODI and be saved in a reservoir. Alternatively it could be used for irrigation or other users. Even if the water just went down the drain it's only roughly equivalent to taking a shower.

Any thoughts on this? What sort of heat exchanging coil would be good to use?

 

[Mr. Ugly]

That's how I cooled down wort when I was homebrewing.

Stuck a big coil of copper refrigeration tube in the kettle, and ran tapwater through it.

I did 2 stages of cooling. Tapwater, then icewater.

You could use a titanium coil.

How about geothermal cooling? If you bury a large container of water in your yard or under the house, you could use a circulation pump on a controller to run the cold water through your heat exchange coil.

 

[sfsuphysics]

that's a trick to use for RO units to warm up the input water as well. You could get away with simple plastic tubing if you're just doing an RO unit simply because the important factor is contact time, since you need enough time for the water(s) to reach equilibrium temperature. Titanium would work too, but might not be as useful as you might think, it'll allow the heat to pass through the tubing to be sure, however then it'll still take just as long for the water to absorb that heat.

If it were me, get a hundred feet of vinyl tubing and toss it in your sump

 

[Gomer]

 

[Roc]

Tony is that a PS job or did someone really do that?

 

[Gomer]

Someone did that. It was part of a gigantic thread at a killie fish forum I used to visit a lot on making an inexpensive DIY chiller. The tank is in Singapore iirc where it is very hot and humid (hence the tons of condensation). Worked quite well.

 

[seminolecpa]

But where is there room for the beer?

 

[Ocean Treasures Aquarium]

my thoughts exactly!!

 

[Gomer]

That is what a full sized fridge is for.

 

[Raddogz]

MMMMMMMmmmmmmmmmmmmm beeeerrrrrrr

 

[hooked]

just a little crude research i came up with this : at 4'-6' deep the avrage ground temperature is 55 deg f.

now the big question is : how big of a hole , how much mass ( concrete or grout ) , what kind of pump rates/volume of water ?

I have been into this idea for a while and have some rough ideas in my head already . Two big concerns come into play though . The first is that in my current setup I would have 3'-4' of lift and need to pump 10' of head . I havent priced the pump but it looks costly . The second is that I wonder if I will actually use less energy in the long run . once again , I need to look into the pumps .

This is something I probably will do and have the perfect house to do it in .

 

[sfsuphysics]

My hydrodynamics is a bit rusty, but if you have a closed loop in the truest form, that's to say not open to the atmosphere at all, you won't need to pump 10 feet of head even if it's 10 feet deep you need to go. Most geothermal heating/cooling systems use the cooling capacity of the earth in conjunction with a heat exchanger so all the fluid in them can be specialized fluids (i.e. not salt water).

That being said I have seen people in the past make very shallow geothermal loops, not sure how effective they were though (me being a newbie to the hobby at the time and all )

 

[badbread]

What about that huge post over on RC where the guy dug a hole in his basement floor, stuck some coil in, etc... I'll try to find the link,

 

[Gomer]

I wouldn't actually plumb your tank water through the ground. Assume a crack happens and then your tank dies. Rather, I would do it as a closed loop heat exchanger. Head height wont matter in this case and you can use a more efficient pump. In this case, you can just use whatever metal piping is normally used for underground work and bury it directly in the soil. The deeper you can dig, the better since the deeper you go, the more "stable" the ground temp is.

On the tank side, you can just use either a lot of poly tubing in the sump, or a compact titanium coil. Titanium will be neutral in your tank (chemistry wise), but a fair bit more $.

 

[Mr. Ugly]

What Tony said

 

[Mr. Ugly]

http://en.wikipedia.org/wiki/Geothermal_heat_pump

http://www.toolbase.org/Technology-Inventory/HVAC/geothermal-heat-pumps

Loop length can range from 250 to 1,000 feet per ton of capacity.

Hmm.... ~80 feet for 4000 BTU/hr then?

 

[hooked]

now this is a post that i wanted to stir up a while ago .

So, the more info I have the closer to doing it I am . I can get my hands on poly pipe for free if its for my personal use . so lets run with that . It would also have to be a closed loop system . I wouldn't want the risk of a tank crash do to some hair brained idea that I couldnt help but do . I also understand that the weight of the water coming down will help with the pump demands but not to what degree .

If I did this I would possibly make it a dual purpose . I have a few posts (one in particular that is right under the tank) that need new piers .

Then how to control the whole thing . CHEAP , but reliable . I dont run a controller of any type so unless someone gave me one thats not an option .

I have 115 gal total vol. What do you guys think ?

 

[Elite]

Mikey, check out this website. She is one of BAR member. She has a giant tank underground.
http://www.exoticcoral.com/new_tank.htm

 

[hooked]

Mikey, check out this

Mikey, check out this website. She is one of BAR member. She has a giant tank underground.
http://www.exoticcoral.com/new_tank.htm



that would be my house If I had a bigger check book


I figure with a four foot or so hole I could get an 80 foot coil of 1/2" poly tubing . The top of the hole will actually be 2-3 feet below the "natural grade" .

Any ideas for a controller?

 

[Elite]

I use ACjr controller. I like it because it controls everything I need, not just temperature.

Why not put a good size container down there? For your tank, I think 50G container is good enough.