DIY Mini Chiller??

I'm thinking this would work - Basically it uses a peltier chip which should need no introduction, so one side gets super cold and the other side hot - thus the heat sink.

Anyways, this looks already pre-assembled, all I'd need to do is drill two holes (one in, one out) for some 3/8" hosing, coil it up inside real good (maybe I could get 3-4 feet coiled up in there) and then get a really slow/weak pump (in-line or submersible would work) to pull water from the res, into the chiller through a few feet of 47' or so temps, and back into the res. I could even insulate the plastic housing to increase the efficiency.

Has anyone tried this? Would it work?

http://www.usbgeek.com/prod_detail.php?prod_id=0651



If so, I wonder how cold the water could be before damaging the roots?? Does anyone know?

sounds like a good way to find out which of your plants has purple genes! you should keep the roots in the 70s while lights are on and can dip them into the HIGH 60s when lights are off.... i wouldnt vary too much though.

OK, 60s to 70s no more no less. Got it.

Since there is no thermostat or adjustable knobs on here, I think what I could do is vary the pump power and also the lenght of the cable until I get the right temp of water coming in to cool the res the right amount to get it to 60-70.

For $30, how can you go wrong?!?!

SmokeDoggy said:

OK, 60s to 70s no more no less. Got it.

Since there is no thermostat or adjustable knobs on here, I think what I could do is vary the pump power and also the lenght of the cable until I get the right temp of water coming in to cool the res the right amount to get it to 60-70.

For $30, how can you go wrong?!?!

Click to expand...

there's a thread on here somewhere were a guy simply stripped down a mini fridge and stuck the colis from it directly in his res, there's a 1-5 thermostat on most mini fridges and they can be bought used for about $20, the thread i saw proved reliable with several tests. on the same thread a guy posted pics of a mini fridge with a similar idea used like yours it had a mini 10 gl or so res inside the fridge which recirculated from and back into his res.

Cool, good info guys, I'm beginning to feel like there might be hope yet for this!

Unless your temps are already pretty cool and you need a 1-2 degree temperature change I don't think this is going to work.

It's made for cooling a beverage which was at room temperature, not fighting heat brought in from another source consistently.

Try saving your money or using one of those mini fridges which will actually be powerful enough to cool the lines.

If I circulate some 50' water into my 70+ degress res, it certainly WILL work. It's just a question of how much water I can cool, how long it takes to get cooled, and how quickly I move it in and out of the res. I agree it will take some experimenting and I likely won't get guaranteed results, but I don't see how it could not work at least a bit.

disposition84 said:

Unless your temps are already pretty cool and you need a 1-2 degree temperature change I don't think this is going to work.

It's made for cooling a beverage which was at room temperature, not fighting heat brought in from another source consistently.

Try saving your money or using one of those mini fridges which will actually be powerful enough to cool the lines.

Click to expand...

depends on the size of his setup.

you could also put a timer on it to keep it from getting too cold or buy a thermometer with a alarm for the water. i have one that goes off if my temps get above 84 or below 65.

if its using a peltier it probly has no direct cold air ventilation and cools from the bottom up kinda like a heat sink in reverse.]

so use a coke can (becuase it will fit) (something with a completely flat bottom would give you better thermal transfer) coil your tubing INSIDE the can, then fill the can with REALLY salty water. (the salt will increase thermal transfer)

but you want my advice. peltier chips are generally not great for long term usage. ive gone through several on my various computers.

so. you know. dont make it neccissary. like dont rig it in such a way that everything dies if it suddenly stops working.

also. instead of pumping water from your res through the chiller, make a closed loop coil.

one coil in the chiller, one coil in the res, with your pump cycling the water in a loop between the two. (again high salinity water will increase thermal transfer, and if copper pipe is used along with a salt water pump you will maintain high efficiency.

Heres that thread i was talking about enjoy
https://www.rollitup.org/grow-room-design-setup/208004-diy-do-yourself-water-chiller.html

Nowitall, Realcloset, thanks for the info. I get what you're talking about, and appreciate the help! Thanks!

FYI, I found them on eBay for $18 shipped and Fry's has them for $24 + tax, what a steal if it works!!!

FYI, my res is only 3 gallons, maybe 2 - 2.5 gallons of water when full to the right height for my net cups... So it's not like I have a lot of water to cool...