Convection DIY chiller?

[Minnreefer]

I just got a strange idea would cooling fins and air movement be able to remove heat from a sump? My brain storm or drizzle is put a large number of cooling heat sinks on a sump or refugium and have a fan or 2 blowing air across the heat sinks, it may not be very pretty but would it help at all?

Just a crazy idea

Jon

[RWD]

Don't know but I'd guess that it wouldn't work unless the surrounding air (that the fan is directing on the heat sinks) is much cooler then the sump water temp. For example if the water temp was 84 and the room temp was 75 I don't think that there would be much cooling. Maybe if you used a fan with a LOT of CFM's. Just my WAG
I have always wanted to experiment with a geo-thermal chiller with a hundred feet or so of plactic pipe burried under 4' of ground. Ground temp at 4' is in the 50's (I think) and should bring the sump temp down a few degrees. The problem is my tank is situated in such a way that I would have to dig up my lawn to try it

[Minnreefer]

I was thinking both things, I have a crawl space under my house that I have thought about putting some line from the tank into the ground, but then I wonder if there is ever a leak or if the pump and friction of pushing the water thru would conter the cooling affect???

I was wondering about the cooling heat sink after I put some on my very warm ballast and that made a huge difference. Just some strange ideas.

Jon

[Casey]

Jon I know people that do the line underground to cool the water problem is you have to get it kinda deep to cool,the more fans I put on the sump the more evaporation is hard to keep up with now about 6 gals a day on my 100.

[Geoff]

if the sump is glass then it might have a chance. if it was acrylic then it would be really slow going. this is the biggest problem with all of the dorm fridge chillers. plastic is a great insulator, so the cold of the outside has a hard time getting to the tank water inside the tube.

now if you had a hundred feet of titanium lying around then either of the ideas would work.

your heat sink idea is basically how those thermoelectric chillers work.

G~

[frlejo]

I have a crawl space under my house that I have thought about putting some line from the tank into the ground,

What if we hooked up the air intake from our skimmers to the line under ground? Just a thought

[Minnreefer]

Along that same line, I have thought about having a drier vent that connects to the fans that cool my lights come from the crawl space where the air is always cooler. I would then have to add a Hepa filter for that air though.

Jon

[kestrel]

Jon,

One that I have thought of is running a coil of SW from the sump through a coil in a shallow, high-surface area tank of tap water and blowing fans across the bath. That way you get evaporative cooling (down to the dew-point temperature) and don't need continual top-off in the aquarium/sump. As long as the air is relatively dry, it should result in good cooling. If you got desparate in the summers, you could also add ice to the bath without salinity concerns. I guess you could even add a cooling coil from an old refrigerator or air conditioner to the bath. Again without concerns for the contamination of the aquarium.

One problem is the top-off on the cooling bath, but that can be fixed with an auto-top-off system. Another problem would be the coil. It needs to have a very good heat-transfer coefficient (like metal, glass would not be too bad). Otherwise the length of coil needed would be too high. I'm still looking for one that I could afford. As Geoff suggested, if I had a good length of titanium tube around...

Another idea that my wife keeps suggesting is running a tube down our 400+ ft. well and back up. It kinda goes on the geothermal cooling plan...

I have not pursued any of these ideas yet, since my 55 gal is in the living room, and does not have the space/location/need for such. I am keeping these in mind for the future fish room in the basement though.

Daryl

[Geoff]

along kestrel's ideas is my DIY chiller is uses a little of each of these ideas. the cooling bath cooled by an old water fountain. it is down in the crawl space so the compressor does not run all the time. the coil is isolated from the liquid in the bath so as not to contaminate. and the liquid in the bath is non-toxic.

G~

[kestrel]

So Geoff,

Do you get good heat transfer with the vinyl tubing?

Daryl

[Geoff]

that is the reason i had to use 70-100 feet worth of tubing. there is enough heat exchange to keep the tank at the desired temp, but just barely.

i am toying with the idea of adding a glass vessel in the bath to help with the heat exchange. glass is a much better conductor of heat than the vinyl.

if titanium was not so expensive.

G~

[Minnreefer]

Good thinking, I am not even sure that I will need one but I think that it would help the temp swings.

Jon

[wanareef]

If I can find the post- on RC this guy tonytooth used a window airconditioner unit as a chiller with a titanium heat exchangerWith a Ranco 2stage controller. Something to to look into.

[Geoff]

Originally posted by wanareef
If I can find the post- on RC this guy tonytooth used a window airconditioner unit as a chiller with a titanium heat exchangerWith a Ranco 2stage controller. Something to to look into.

why? it would be just as expensive as buying one at that point. the titanium heat exchanges are the expensive part. along with most room A/C units being at or above $200.

G~

[RWD]

Here's another idea I remember seeing a looooooong time ago on a web site. The guy lived in the northern part of the US and as you may know the ground is pretty cold even in the summer. Water out of the faucet has to travel through underground pipes so when it comes out of the faucet it's pretty cold. This guy used a laundry tub as a holding container for tap water. He coiled up a lot of hose and put it in the tub as a heat exchanger. The hose was plumbed to the sump in a closed loop with a small pump (powerhead?) for circulation. If I can recall correctly he used a low voltage sprinkler timer and valve to turn on and off the tap water every so often. I suppose you would need a standpipe or something to keep the tap water in the tub say half full but not overflow when the timer turned the valve on.
That's all that I can remember and I don't know how well it worked. What do you guy's think? If the tap water was 60 and the tank water was 80-82, would there be enough pull down? Just an idea to kick around. Bob