DIY Chiller

[supersecretshinto]

This is my idea for an ubercheap nano chiller. Total production cost I am estimating at under $40. Life expectancy of the unit is practically infinite. The unit doesn't run on electricity so it will be uneffected by power outages. Even if you already have a chiller it may be beneficial to rig one of these up and never connect it. Could come in handy when the power goes out and the temp in the house climbs into the 90's, sometimes for days, before power is restored. However, this method of cooling does have one drawback and that is the need to drill two .25 inch holes in the floor or baseboard near the tank. If you own your home, no problem. If you rent and are handy with wood putty and matching stain, again, no problem. If there is carpet down that will cover these tiny holes until long after you leave......

 

Anyway, here's the plan. This is a "wastewater" chiller. The diagram I have drawn is of an in-line unit. Water comes out of the cold side of a tap at about 55F regardless of season. My idea is to splice into a cold water pipe near the tank with an icemaker waterline kit. These kits run about $15 with the line-tap, valve and plenty of plastic tubing. This waterline will lead to a reefsafe coil of metal tubing that acts like a radiator. This would be the main assembly and a second hose would then route the water to a drain (preferably in the basement to where the A/C condensation is routed) or to a container to be utilized in some other way (watering plants, etc... or for recirculation from the container to the coil making the container your cold water source as well). The temperature can be controlled with a needle valve mounted where you can get at it. If you run out of tubing, just buy some by the foot from the hardware store. Once you get it adjusted pretty close the heater can counteract any slight overcooling. The water should barely creep thru this thing for it to work and it's impact on your water bill should be nearly inpercievable (unless the wastewater isn't being utilized). Like I said in the begining, the hardest part is the plumbing. $40 is also a very liberal estimate. The projected price under my cicumstances is more like $30. I will post some pics as it is built but I am going to the Bahamas on vacation soon so it may be a while.

 

I would appreciate any and all feedback on this idea before I start.

[supersecretshinto]

I know some of you may be thinking that if the power is out, so are the pumping stations. True. But the pumping stations will be at the top of the list of places the electric company will want to restore power. Your house, not so much.

 

Also note that the in-line model is the most useful design. In an emergency, coupled with a battery powered air pump and bubblestone, this little jammy could save your tank by providing cooling and at least some water movement when placed in the display.

[kgbenson]

This is my idea for an ubercheap nano chiller. T

 

INteresting design. Consider makeing it even more of a countercurrent heat exchanger by feeding a tube within a tube and then coiling it up to save space.

 

For schematics look up counter flow wort chillers - though you would not use the copper tubing . . . but you knew that.

 

http://webtrolley.org/mivastore/merchant.m...egory_Code=1076

http://www.wineandhop.com/CatalogBeer/wortChiller.shtml

http://hbd.org/jdbrown/chiller.htm

 

Keith

[supersecretshinto]

Did you say wort chiller? You must be a fellow zymurgyst! Great suggestion! I was aware of the device but somehow unable to make the connection for myself. Thanks!

[TheNorthernLight]

what type of "reef safe" tubing are you intending to use?

 

cause that's the hard part to find.

 

Titanium, not unless you have a 20K Lbs press machine,

 

Stainless steel... needs to be manufactured.

 

I can't find anything else that's viable....

 

Oh, and btw, I've tried this with polyvinyl , polyethelene, and several other types of plastic tubing and none of them make ANY difference, unless you run refrigerated water through it.

 

I REALLY like this idea, however it seems a little on the , missing materials side.

 

Hope you found something else to try.

 

Spyrule.

[Tony]

This may be a dumb question but what about aluminum tubing?

[Raskal311]

The only “metal” heat exchanger I can think of is titanium, which is very expensive. Stainless steel will work but can rust over a period of time especially in salt water. You can also use plastic tubing but would not be as efficient but will work. The design also seems to produce a lot of waist water to me. I mean even at a slow pace it would produce 50-100gal a day easy. Have you seen how much waist water an ro/di unit produce? It’s just about the cost of the water but a waist of a natural resource. What I do with my waist water from my ro unit is save it in a 150gal container to water my grass. Another thing is that I would reverse the two, cold water on the outer shell of the mettle heat exchanger and tank water on the inside. Another thing is if you don’t have electricity then your ice maker wouldn’t be making cold water would it?

 

What I may try is to have a coil of tubing plumbed to my min fried that is already next to my nano. A single stage rancho controller and a small water pump to run it.

 

 

BTW I have been play with this idea for awhile and a good way to get a titanium heat exchanger is salvaging it from a broken chiller or maybe a frig.

 

This may be a dumb question but what about aluminum tubing?

 

It’s to soft and brittle, also it would be very hard to find aluminum tubing/coil. Other wise it should make a great heat exchanger.

[Tony]

Dont ice probes use an aluminum heat sink with some kind of rubber coating? Thats what it looked like on mine. I ask because I thought about trying to use parts from a mini fridge and just coating the heat sink?

[Raskal311]

Iceprobe is a diff type of design, heat sink vs. heat exchanger. This design calls for a heat exchanger.

[supersecretshinto]

what type of "reef safe" tubing are you intending to use?

cause that's the hard part to find. I REALLY like this idea, however it seems a little on the missing materials side. Spyrule.

 

If a suitable tube cannot be found, could I not use a less suitable one and paint it with the marine epoxy paint you all use to waterproof wooden hoods? Should adhere well, is reefsafe and waterproof. Can't imagine that it would hamper the heat exchange too much, either.

 

The design also seems to produce a lot of waist water to me. I mean even at a slow pace it would produce 50-100gal a day easy. Have you seen how much waist water an ro/di unit produce? It’s just about the cost of the water but a waist of a natural resource. What I do with my waist water from my ro unit is save it in a 150gal container to water my grass. Another thing is that I would reverse the two, cold water on the outer shell of the mettle heat exchanger and tank water on the inside. Another thing is if you don’t have electricity then your ice maker wouldn’t be making cold water would it?

 

Collecting the water for some other use I had already mentioned. If it is still too much than I would suggest putting a large reservior in the basement where it is very cool and use a pump to circulate the water from the reservior to the coil. You already have that 150gal reservior just sitting around anyway. You could always still tap a pipe in an emergency. I'm not sure how much heat an ro/di puts into the wastewater but if it isn't much and the ro/di is already wasting a ton of water....seems like this system would be ideal in your case. In my case, I always can use more water as I have 18 freshwater setups holding nearly 400 gallons in my diningroom alone (if i use the wastewater method and collect it). Also, I plan to build a 250 gallon koi pond in my basement at some point (big cold reservior) and circulate it's water thru the chiller instead (recirculating method). The straight-up "water down the drain" method is best for the emergency use aspect.

 

Also, I hate to gnit-pick but, water is not a natural resource that can be wasted. Do you think that once it goes down the drain that it just disappears, never to be seen again?

 

What does my icemaker have to do with anything? The water is cold enough right out of the pipe. No need to connect it to the fridge.

 

Reversing the two water paths, however, is a good idea. But coating the inside of it may be a challenge if a reefsafe coil cannot be found. Thanks!

 

Dont ice probes use an aluminum heat sink with some kind of rubber coating? Thats what it looked like on mine. I ask because I thought about trying to use parts from a mini fridge and just coating the heat sink?

 

Now here is a guy with a "can do" attitude! Rubber might insulate too well, but coating the coil is a dandy of an idea regardless of the metal's composition. Good point!

[supersecretshinto]

I would also like to make clear that if the source of cold water is a reservior it would not have to be anwhere near 250 gallons to get the desired shift in temp. I don't think it would take any more than 20. I haven't done the math or conducted any tests yet. Of course, it all depends on how much water you need to cool and how many times the reservior water is circulated in a day and how efficient the coil ends up being. Crafty individuals can score 55 gallon plastic drums for next to nothing on a regular basis. Plastic tote, old tank, whatever.....

 

I still don't believe that there is any good reason why this won't work (other than actually trying to find excuses for it not to). Get creative! Skepticism IS appreciated but I need believers here. Help me perfect and stream-line this thing and bring it in on time, way under budget, working well and looking good! Anyway, this is my "Parsimony Division" challenge to you.

[supersecretshinto]

Ok, I believe I have solved the "finding a reefsafe coil that's inexpensive" problem presented by spyrule and raskal311.

 

5mm OD flintglass tubing (used in conjunction with rubber stoppers and scientific beakers in labratory settings). These glass tubes can be heated with an alcohol burner until glowing and quickly bent into the desired shape. They only come in 1 ft lengths here, but are packaged 6 for $3.00 .... http://unitednuclear.com/other.htm I am sure they can be found localy (and possibly in longer lengths and cheaper) but this site was to much fun to browse for me to resist linking it to this thread.

 

So there you go. 6 feet of 5mm OD shapeable glass tubing for $3.00. Should be easy to connect together and make one hell of a good coil. Anyone see any problem with this?

 

Also, this discovery will make it possible for me to consider the improvements suggested by kgbenson and raskal311.

[supersecretshinto]

I've just done a little figuring and if I doubled wound the coil, I can make roughly sixty loops in a six inch assembly. Bit more labor intensive than I had planned and I will probably have to get extra tubing. (probably gonna break a few getting the feel for it). I want to limit the length of tubing used to 12 ft.

 

Can anyone tell me how round the pvc casing would have to be to accomodate such a coil?

 

(Based on the need to buy extra materials I'm going to have to ammend the cost of the coil to more like $9.00.)

[supersecretshinto]

Apparently, the thing I have been trying to build here is called a Graham condenser (pictured below). I discovered this about the same time I came up with the flint glass tubing idea, but after an exhaustive search for one with the right dimensions for the right price I have decided to go ahead with the glass tubing idea with one change. I will be using PYREX tubing because it is way stronger and the walls are much thinner so I can maximize the efficiency of the coil. One other change is that I will be going with 6mm tubing because it is closest to being .25in. in diameter and is the largest size I can use before the wall thickness jumps. the wall thickness is about 4/100 of an inch wich should make for some good temp exchange! (I did end up finding longer lengths cheaper....and Pyrex!)

 

Since my project is no longer missing any parts I am going to have to start dealing with the challenges of working with glass. IT IS FRAGILE. I'm glad I cant use a pre made Graham condenser because the coil is attatched to the jacket, wich is also glass and very fragile. This way I should be able to engineer some kind of shock absorbtion qualities into this thing (Having a PVC jacket is a start). I want to keep the glass entirely inside the casing and mabe attatch it to a bulkhead on the inner wall of the casing with a flexible tubing of some sort so it kinda floats.

 

Any other ideas on shock absorbsion?

How to go about bulkheading on such a small scale with tight space restraints?

What would be the easiest and most versitile casing?

Should this go into part of the system or be a stand-alone unit? both?

Trying to limit jacket size to 6"long x 2"diam. max. Any possible jacket besides PVC?

 

Projected coil cost still around $10.

[supernip]

We use these in my chemistry class for distillations. It's all glass and it works really well but I think the hardest part is gonna be getting that thing water tight. The fittings aren't that reliable imo, plus it's sealed with grease. I guess if you hook up a pump to run the water from the sump, and one for the waterline, it'd work well. Kinda like running it through a refridgerator I suppose? I know in my area though, the water temperature during summer isn't that cold. Plus I don't know about the conductivity of pyrex... They do get really hot when heated in a sand bath though =/

 

The water is going to have to run pretty quickly through the water condenser too... or well, thats how I run it when I'm distilling. Anyway, I can take a pic of it for you if you want. I thought these things were supposed to be expensive... my lab charges like 50 bucks for a broken water condenser. It's an interesting idea, I might have to steal some lab equipment now.

 

Please keep us updated

[supersecretshinto]

We use these in my chemistry class for distillations. It's all glass and it works really well but I think the hardest part is gonna be getting that thing water tight. The fittings aren't that reliable imo, plus it's sealed with grease. I guess if you hook up a pump to run the water from the sump, and one for the waterline, it'd work well. Kinda like running it through a refridgerator I suppose? I know in my area though, the water temperature during summer isn't that cold. Plus I don't know about the conductivity of pyrex... They do get really hot when heated in a sand bath though =/

 

The water is going to have to run pretty quickly through the water condenser too... or well, thats how I run it when I'm distilling. Anyway, I can take a pic of it for you if you want. I thought these things were supposed to be expensive... my lab charges like 50 bucks for a broken water condenser. It's an interesting idea, I might have to steal some lab equipment now.

 

Please keep us updated

 

Thanks for your input. I don't have much experience with chemistry equipment (obviously). Any visual aides would be appreciated.

 

I have seen high efficience condensers of this type selling for up to $150. The cheapest I could find was $20, but it was shoit. At least since I'm making my own I can avoid the questionable fittings problem (thanks for the heads up on that).

 

As for the speed of the water, I probably just won't know till I try it. I suspect you may be right, though. I have abandoned the pipe tapping method in favor of circulating the water to a container in the basement where it is much cooler and am hoping the temperature difference will be enough. I plan to conduct my tests with a 20 gallon reservior and see what happens. If it warms up and stops working I'll try a bigger one. I sure hope I can pull this thing off without the system being to big and clumsy.

 

Thanks again!

[Raskal311]

Don't know about coating with plastic but I like the glass idea. Coating with plastic resin is not full proof and plastic is a very good isolator so it would take away too much of the heat exchanging property of the metal. Ohh and another reason why aluminum wouldn't work very well is because it can oxidize.

[supersecretshinto]

Good to see you back raskal311. Didn't know if you would be since I got a little defensive on you in reply to your last post. My bad. Thanks for weighing in on the glass idea. I wasn't really able to find an answer anywhere on how good it conducts temperature. Manufacturers of glass say it conducts very well (probably because they are wanting to sell more evpensive thermal glass) but sciency types say it doesn't (probably because they mean in comparison with every other material in existance). I wouldn't have dreamt that it would be so hard to get a straight answer on such a simple question. I think it will work like a champ. Thanks for the vote of confidence.

 

And, yeah, aluminum oxidizes. I understand that having it annodized helps, but I ruled it out because of the cost factor. Thankfully the glass has no need for coating and will be safe on both sides of the coil so I can use a reservior that is an inhabited coldwater tank.

[Raskal311]

I've read that glass is a poor heat/cold conductor but I imagine you would be using thin glass which should work ok.

[EL CHUPACABRA]

I blow glass and am creating my first nano tank currently. I have a 5.5g that will be divided with a refuge/sump. I haven't got lights yet so I am not sure how much Heat reduction I will need. I am planning on putting a pyrex coil inside the refuge with a thermocouple inside the tank. The thermocouple will be hooked to a tempature control module I had for my Keggarator, it just turns on a ac outlet (ie where the pump pugs in) when the tempature excedes its setting. Inside the empty mini fridge in my room (garage sales), will be a bucket of cold water with a pump in it. The pump pushes cold water through the coil in the tank. Pyrex is completly inhert, and you can throw way more caustic cemicals at it than salt water. The coil will get as cold as the water inside it (from bucket of cold water in fridge) and it will begin to cool the tank. When the the tank is at the proper tempature set on the controller box (detrimed by thermocoupliung in tank), it will shut off the pump and the light will begin to heat up the tank again. Repeat... The tempature control unit I have is acurate within 1 degree farenheight so it should be pretty damn acurate. But i dont even have water in my tank yet, or lights so who knows if I will need cooling, but I do live in the desert.

 

With that said, don't be under the foolish impression that you are going to just hop on a glassblowing torch and make one of these. Even if you did some how manage to make one of these it would need to be annealed at 1050 degrees F in a digital computer controled kiln otherwise, invissible stress in the glass caused from a uncontrolled cooling would cause the glass to crack eventually. In other words once you heat the pyrex glass above its strain point of 925F you can add permant stresses to the glass that will eventually cause cracking. The working tempature of the glass is around 1700F. I think my glass blowing torch runs around 2400F its hard to tell, i dont have a thermometer that goes that high. The torch runs on propane and pure oxegyn to get a wicked hot flame, way hotter than anything i have ever seen other than the sun. Borosilicate (pyrex) glass has a very low COE (coefficent of expansion), COE 33, this means that it does not expand much when it is heated. (glass cannot handle expansion with the exception of pyrex, that is why you can put pyrex dishes in your hot oven, and why glass pipes are made out of it.) The lead glass you spoke of is workable at a much lower tempature, but it would not be able to handle rapid tempature fluxes and would simply crack if you tried to change its tempature to quickly, just like when a hot heater cracks in cold water. I am not trying to be mean, I am just warning you that it is very difficult, and glassblowing equipment is very expensive, Nano reefs seem cheap to me after my glassblowing hobby. I burn up a $40 220 cubic foot tank of oxygen in 4-6 hours. Plus the cost of glass, kiln electricity, etc. It is out of controll, that is why a german condensor is so expensive. Scientist especially chemist spare no expense when thay need something, pyrex was chossen for scientific glassware beacuse of it low COE and the fact that you can throw some of the most caustic chemicals in the world at it and it doesnt even get phased. Also it can be easily cleanded. You have definatly found the right material for your coil, I Worked at beer brewing store so I got this idea from wort chillers and from scientific glassblowing knowlege i have.

 

If you want I can give you exact instructions on how to make the coil. But first see if you can even melt some boro (pyrex). It takes a hot torch.

 

I've read that glass is a poor heat/cold conductor but I imagine you would be using thin glass which should work ok.

The glass is not so much the heat conducter as the water around it, It will work, pyrex is used in almost all chemistry labware, it will be a tempature between the warm water outside it and the cool water inside it. Trust me, I am a borosilicate

(pyrex) glassblower.

[dga]

enviromentally bad idea. water in not finite.