Water chillers?

Cubes15128 said:

Hey guys I've got a 5gal dwc bucket and I've been struggling to keep my water temps consistently below 70f. I've got my bucket sitting in a tub that I fill with ice/frozen water bottles when I wake up and also when I get home from work. By those times the ice is melted and temps back up so I feel like what I'm doing is a waste xD I've heard people talking about water chillers n such but never seen what exactly I need to get to make one! I see chillers on amazon but they just look like a plastic box that I need to add parts to chill water how I want to. ?? Lol any help like parts lists would be awesome! Or even a good all in one kit! Thanks in advance guys!

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Try wrapping your bucket with insulation, then putting it inside an igloo type cooler and sidefill with blue ice paks

I've done three things that keep my temps at 68f/20c:

1. Blow air across the surface of the water with a fan. This is "evaporative cooling". You have to leave the lid off to do this, so the heat in the reservoir can dissipate. I have taken this one step further and ran a length of flexible duct from my floor vent to the reservoir, which really helps keep temps in check.
2. Insulate the reservoir so that the ambient room temperature doesn't warm up the reservoir walls. I wrapped mine with a blanket.
3. Use a small fan to cool the water pump. This really helps! You can use a DC PC fan, or an ac bread fan, which is what I'm using. It's a little hard to see in the pics.

If all else fails, freeze water jugs and use them throughout the day, like ice cubes. This is a pain, and you give up freezer space, but it does work well. Use a little salt with the water in the jugs, to freeze the jugs even colder.

Larry3215 said:

Atomizer suggested using an old, small chest freezer as a chiller. You can get them cheap used. Just hook it up to a cheap temp controller to turn on/off and put your buckets/rez inside. You can close off the top with a foam insulation lid. Wont work in every case, but possibly a cheap option for some.

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This won't work. You'll burn out the compressor motor because it'll run all the time trying to cool water that's constantly being warmed up. It's basically the same thing as leaving your freezer door open. At that point, you're just trying to chill the outside air.

How high do your temps get?

JSB99 said:

This won't work. You'll burn out the compressor motor because it'll run all the time trying to cool water that's constantly being warmed up. It's basically the same thing as leaving your freezer door open. At that point, you're just trying to chill the outside air.

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67f to 68f. It never wavers! Works awesome!

JSB99 said:

This won't work. You'll burn out the compressor motor because it'll run all the time trying to cool water that's constantly being warmed up. It's basically the same thing as leaving your freezer door open. At that point, you're just trying to chill the outside air.

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If it works for cooling a root chamber, I dont see why it wouldnt work for this application. You wouldnt leave the top open, and you wouldnt fill the freezer with water, and the compressor would not run continously.

Put your rez inside the freezer, but put a spacer under it so the top of the rez is even with the top of the freezer. Then cover the top with insulation, and cut holes for the plants. Or just cut a hole in the freezer lid to recess the rez into.

Then do exactly as Atomizer suggested, and use a temp controller to cycle the freezer on/off to control the rez temps. If you put some containers, or jugs of water in the bottom of the freezer, and around the rez, to fill up extra space, that would also act as a thermal sink and should reduce cycling of the compressor.

On the other hand, I dont see why having the freezer full of water - using it as the rez - would be any different from having it full of frozen yogurt pops. In this case, you are not relying on the freezers internal thermostat to control things. You're using the temp controller. Plus, if the top is insulated, there would be no extra heat loss over normal use.

Oh, wait. You guys are talking about having the rez inside the grow tent or grow room where the temps are constantly hi. That would be more problematic, I agree. I was picturing my situation where the grow tent is raised up on a table, and the rez would be at normal room temps, and not subject to constant heat input.

Larry3215 said:

On the other hand, I dont see why having the freezer full of water - using it as the rez - would be any different from having it full of frozen yogurt pops. In this case, you are not relying on the freezers internal thermostat to control things. You're using the temp controller. Plus, if the top is insulated, there would be no extra heat loss over normal use.

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If a freezer full of water took 374 btu to lower the temperature by 1 deg F, the same freezer full of dry air would only take 0.11 btu

Atomizer said:

If a freezer full of water took 374 btu to lower the temperature by 1 deg F, the same freezer full of dry air would only take 0.11 btu

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True, but you need that same 374 BTU to cool your rez water by 1 deg - assuming its the same volume of water. Its true that a rez will have constant heating going on from pumps, etc, but any other chiller you use will also have to handle the same amount of heat. I dont see any difference there - other than you can often pick up a used chest freezer for next to nothing.

As far as it cycling faster than normal, and wearing out or something, I dont buy that. When I was a kid, we lived in Phoenix, Arizona. We had an old used chest freezer sitting outside on our carport year round. It was often well over 100 F during the summer. The compressor on that thing ran 24/7 for large portions of the year. Chest freezers are used all over the world in similar situations. Im sure many of you have seen freezers or coolers sitting outside, in the sun, at gas stations or stores. There are freezers full of ice sitting outside, in the sun, at some of my local grocery stores. Maybe they will only last 15 years instead of 25, but its not going to burn out with a few days of hi usage in a hot environment.

The ice and frozen produce is only stored in the freezer so its already frozen when it goes in. Keeping something frozen takes a lot less energy especially if the container is well insulated

Atomizer said:

The ice and frozen produce is only stored in the freezer so its already frozen when it goes in. Keeping something frozen takes a lot less energy especially if the container is well insulated

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Again, I agree completely. But a chest freezer sitting in the sun on a 110 deg day is going to be working as hard as it possibly could. As Im sure you know, insulation is not perfect. Heat always transfers through it. Its just a question of how fast. That freezer sitting in the sun is going to be working a lot harder than it would trying to keep a few gallons of water a few degrees below ambient on an intermittent schedule. Like I said, ours ran pretty much 24/7 during the summer for at least the 15 years we lived in that house - and we bought it used.

Plus, to me the key point here is that the same logic, and the same math, applies equally to keeping a rez cool as it does to keeping frozen yogurt cool. No matter which "chiller" type you choose, and no matter how you do it, you are going to have to remove the same amount of heat over the same time period. Why not use the least expensive option - assuming you have room for it?

I doubt very much that one of those expensive chillers is significantly more efficient than a typical home chest freezer as far as BTU/$ of electricity used. It would have to be a LOT more efficient to pay back $500 plus at my electric rate - $.09/kwh. I know for sure that the Peltier type chillers, especially the cheaper ones, are grossly inefficient.

The only downside I can see to using a chest freezer - aside from the bulk - would be if it was inside your tent. Any heat removed from the rez would just add to the tent heat load - but once again - that same thing applies to any chiller you use inside your tent.

Its kind of odd trying to convince you that YOUR idea was a good one!

A chest freezer would probably not work well given the temps your trying to maintain. It would chill the water quite well once the water reaches temp but they are designed to run and evaporate the refrigerant at a lower temps, below 32. By trying to maintain res temp water, I run my res at 66, you are running way higher than design so the likelyhood of a compressor burnout is high. It would be interesting to try though.

1) Its a closed system. The starting temperature of the water wont make any difference, other than it will take somewhat longer to cool down the hotter it is to start with.
2) Also, your going to be turning the compressor on and off with an external thermostat. It wont be any different from starting it up the first time you plug one in, before it cools down.
3) This is no different from how any chiller or any refer works. Its also just like your home refrigerator, which keeps food above freezing on the warm side. My fridge can be turned up to around 50 F with its internal thermostat.

The fact your not trying to cool the water down to freezing will actually make it work less hard because of the smaller temp differential.

Ok, even though Im right, and you guys are all WRONG, I'll stop arguing. Im obviously in the minority.

Sorry to let you down Atomizer. I gave it my best shot

Larry3215 said:

1) Its a closed system. The starting temperature of the water wont make any difference, other than it will take somewhat longer to cool down the hotter it is to start with.
2) Also, your going to be turning the compressor on and off with an external thermostat. It wont be any different from starting it up the first time you plug one in, before it cools down.
3) This is no different from how any chiller or any refer works. Its also just like your home refrigerator, which keeps food above freezing on the warm side. My fridge can be turned up to around 50 F with its internal thermostat.

The fact your not trying to cool the water down to freezing will actually make it work less hard because of the smaller temp differential.

Ok, even though Im right, and you guys are e all WRONG, I'll stop arguing. Im obviously in the minority.

Sorry to let you down Atomizer. I gave it my best shot

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Everything you said is pretty much correct, Also setting temp differential would stop cycling. I’m a refrigeration mechanic and the only draw back I see is excessive superheat at compressor if trying to maintain higher temps than the design. Like I said it would be a cool experiment and a relatively cheap one.

Outdoors you can make a traditional underground cooler....You need a hole, probably 6x4, and about 3 feet deep.
inside the hole you build a chest out of bricks... by just stacking them in a rectangle... wet them down, put what you need top stay cold in the middle and cover the top with wet boxes, plastic,tarp whatever...(you gotta build it in the shade though)

There are youtube vids showing how.

There's a really good first time grower thread on 420 using an ice probe.. Google - dwc scrog ice probe chiller..
For $200 you can get a ice probe, controller/power supply and an aquarium temp probe from amazon..

https://www.amazon.com/IceProbe-ThermoelectricAquariumChiller/dp/B001JSVLBO/ref=asc_df_B001JSVLBO/?tag=hyprod-20&linkCode=df0&hvadid=198088359792&hvpos=1o5&hvnetw=g&hvrand=14185177460467501576&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1022651&hvtargid=pla-319865085565&psc=1..

good set

Ok so im going to hook you up on sum game bro. Dont buy an expensive watwr chiller. Spend 120 to 150 and get a small fridge with the freezer on top. Now take a 400 gal/hr pump and put it in your res. Buy a roll of plumbing copper with 3/8 in od. Also grab some pvc tubing 1/2 in od and 3/8th in id. The 1/2 in pvc tubing hooks one end to your pump the other end to the 3/8th in copper. Now drill two. Holes in the fridge on the side. One is an inlet one is an outlet. Take your curled up copper and put it in the fridge push one end out each hole. You will need to het an interval timer from amazon. About 20 bucks. Now here is the tricky part. Set the fridge on the coldest it will go. Wait a day for it to get to temp . Should be about 38 degrees. Set your timer to 1 min on and 5 mins off. It will come on 10 times per hour and run your water thru the curled copper in the fridge and reduce your water down to about 60 degrees to 65 degrees. Test run it for a day and then measure your water temp. If it is under 60 turn your off time up. If temp is over 70 turn your off time down. The whole setup should cost about 200 bucks at most mine was 160 and keeps res twmos in a 15 gal reservoir at 63 degrees.

I wonder what the comparison to efficiency is on these products DIY vs Factory Made. What is the BTU Transfer rate when converted to cool water instead of air?

This ones 300$ and rates up to 50 gallons plus it comes with a warranty:
https://www.amazon.com/gp/aw/d/B07BHHQLKR/ref=dp_ob_neva_mobile

Chiller Reviews:
https://fishtankadvisor.com/best-aquarium-water-chiller-reviews/

Definetley taking the advise of the titanium system as well.

I got lucky I stopped in at the local hydroponic store for hydrogaurd and they had 5 or 6 used chillers ranging from 1/10 hp to 1/2 hp got the smaller one for $65 or $70 so might want to check around local supply stores.y they only wanted 120 for a bigger one