PDA

View Full Version : Chiller recommendations



Jonathan Bowen
05-27-2014, 10:34 PM
So I can't seem to fix the environmental issue so I have to turn to something else. I moved the laser into an old cooler at the new retail location. However, It's having adverse effects because the laser water temp is rising faster then I'd like. It's also taking forever to cool off. I usually start about 24C and end up at 28C rather quickly. Not sure if I want to go over that too much. I have a CW-3000 right now. The CW-5000 is nice but I can't swallow $700 at this point. Any other suggestions for getting the water temp down? I have considered a suggestion from a friend. He said to take a 5 gallon bucket and mount copper tubing in it. Then drop a frozen jug of water in it in the morning. It would require a but of plumbing and some maybe $100. Not sure I like the idea or not. I guess it wouldn't drop the temp too far. I'm assuming that lower is better until it reaches the freezing point and that would be impossible as my coolant is frozen water.

any thoughts or ideas other people have tried?

Rich Harman
05-27-2014, 11:27 PM
If the water is too cold you can get condensation, you don't want that in your machine.

If I were in your situation I would look into using a garden hose set to a trickle to continuously replace the warm water in your bucket.

Adrian Page
05-27-2014, 11:44 PM
Buy a cheep 5000 BTU air conditioner at Walmart and aim it at the intake of the CW3000?

Adrian

Jonathan Bowen
05-28-2014, 1:19 AM
I tried getting a fan and putting it at the entrance to the cooler and opening the glass door near the laser. It chilled the room better but still having heat problems with the water. I also don't want city water flowing through my laser tubes.

BTW the cooler is defunct or I'd just turn it on :)

Dan Hintz
05-28-2014, 8:22 AM
Someone recently posted their DIY water chiller... a water cooler from Wal-Mart (or similar) with no water bottle, just the input/output lines going into the main tank. Couple hundred bucks, if I remember correctly.

Adrian Page
05-28-2014, 9:44 AM
A 5000 btu window air conditioner is more powerful than a CW5000 chiller with about twice the cooling capacity. Someone should try it. I will when my laser gets here. I ordered the CW3000 and intend to strap a cheap window A/C unit to it. I think the cold air from the AC unit blowing through the radiator of the CW3000 will work just fine. Seems like simple physics... blow cold air through a radiator.

Adrian

Jerome Stanek
05-28-2014, 10:22 AM
You can get a CW 5000 from Automation Technologies for $498 plus shipping.

Jonathan Bowen
05-28-2014, 11:04 AM
I'm really kicking myself now. I had an old water cooler laying around. I gave it to someone and I can't remember who...

Clark Pace
05-28-2014, 2:35 PM
Hello,

Yeah that was me. I use a water cooler. I also thought of buying a small fridge. Drilling a few holes in it, just have a small bucket of water in the fridge.

matthew knott
05-28-2014, 2:59 PM
Adrian Page's idea is spot on, blow cold air DIRECTLY over the heat ex-changer on the CW3000 will work perfectly, a fan cant actually lower temperatures lower than the air its sucking in (room temp) but a cheap air conditioner should be able to blow air at less than 10 deg C. Also if you look at the spec of the water coolers its clear that these will achieve next to nothing in additional active cooling, they are ok at cooling a fixed body of water over a long time, like a few gallons down to 15 deg C over a few hours. But they are all Thermo-electric coolers with less than 50 watts of cooling, and in the grand scheme of things its going to do nothing. It would allow you to cool your water overnight (in the tank) and then if you ran for only a short time you would be in a much better position as you are starting with cold water but you might as well chuck a few ice cubes in the calling water, in fact a few ice cubes would have more effect.
You could use the 'coil of copper' method but instead of ice cold water in the bucket have a slow flow of city water in and out as the water out of the ground is pretty cold and stable, or if you can get a copper coil in the tank of your CW3000 just run city water through this, just a trickle would be a big help. We used to cool 18kW of flash lamps down to 20 deg C using one city water outlet, imagine a tap running flat out all day, not very environmental friendly as the water was just dumped onto waste ground behind us (we had no water meter) but you should have seen the size of the plants that grew, it was like a jungle!!


You need to be looking for about .7kw or 2500 BTU of cooling, that should allow you to run all day with no worries at all, aquarium chillers work fine but they cost the same as the CW5000, which to be fair is great value at under $500

walter hofmann
05-28-2014, 3:21 PM
hi all
here are my solution to cool the laser water and at the same time the room. I am in florida and our temperature mostly exceeds 85F and with this the workroom temperature goes up to 85 to90 F too.
I use a window A/C unit did put inside the outlet canal a 120x120mm radiator and use a 1.5gallon tank with a submersible pump.
this setup holds the cooling temperature between 68 and 71F but also the room ( Garage 600SF) by 79F.
( see picture)290282290283

greetings
waltfl

Kev Williams
05-28-2014, 7:12 PM
Living in the 2nd driest state in the country has its benefits-

Yesterday I was cutting plastic in my near 90 garage, water temp got to 35c (all I have is a 3000 chiller)

Today there's a small swamp cooler in the window, and the garage is now around 74, and the laser is running at around 25c.

Nice thing about swamp coolers, is the electricity they DON'T use vs refrigerated.

For those of you entertaining the idea of a small 5000 btu refrigerated AC unit, Home Depot has the small LG for $119. I bought one identical to it 8 years ago and it still works like new. They won't cool a huge room, but I'm betting if it's sitting next to a 3000 chiller, you'll never have hot water issues!

Keith Colson
05-28-2014, 9:39 PM
I don't know if this has been mentioned but a dehumidifier would offer a nice compact solution. You would need to couple a copper pipe on to its cooling side but not too hard. You would also need to bypass the humidity sensor or get tricky and replace it for a temperature sensor. Just an idea.

Adrian Page
05-28-2014, 11:21 PM
What attracts me about using a $100 5000btu air conditioner and a CW3000 chiller is that it has twice the BTU cooling ability of the CW5000 chiller for half the cost. You still get the CW3000's pump,tank, alarm and thermostat. The original poster already has the CW3000. Dehumidifiers cost about twice what a small a/c unit costs. As far as I can tell, the modifications required to use a window a/c unit would be to plunk it down next to the CW3000 and plug it in.

Adrian

Adrian Page
05-28-2014, 11:27 PM
hi all
here are my solution to cool the laser water and at the same time the room. I am in florida and our temperature mostly exceeds 85F and with this the workroom temperature goes up to 85 to90 F too.
I use a window A/C unit did put inside the outlet canal a 120x120mm radiator and use a 1.5gallon tank with a submersible pump.
this setup holds the cooling temperature between 68 and 71F but also the room ( Garage 600SF) by 79F.
( see picture)290282290283

greetings
waltfl

Way to go Walt! Simple, cheap, effective and you get your workshop air conditioned to boot.

Adrian

Glen Monaghan
05-29-2014, 1:11 AM
A dehumidifier is basically a window AC sort of unit with different packaging, reconfigured airflow, and condensate management (bucket and/or hose), for a higher price than similar cooling capacity AC unit.

David Somers
05-29-2014, 11:10 AM
Adrian,

One thing to keep in mind with a window based AC unit, any AC unit for that matter, is that it is generating heat in the process of removing heat from the air it is blowing out. It is not a zero sum. You need to have some sort of outside venting for it or your room will gradually get warmer. That doesn't mean don't do it, just that you shouldn't just set it on the floor and aim it at your CW3000 other than to test the idea. For that matter, the CW3000 is generating heat as it chills the water. And so is a dehumidifier. I have an old boat and I used to run a couple of 100 watt heaters in it to keep condensation/mildew down during the winter. I switched to a dehumidier when I lived in it since I was adding so much moisture to the air by living there. With the dehumidifier running I didnt need the heaters going. It heated the air far more than those 3 heaters did.

Dave

Eduardo Rivera
05-29-2014, 11:41 AM
So I can't seem to fix the environmental issue so I have to turn to something else. I moved the laser into an old cooler at the new retail location. However, It's having adverse effects because the laser water temp is rising faster then I'd like. It's also taking forever to cool off. I usually start about 24C and end up at 28C rather quickly. Not sure if I want to go over that too much. I have a CW-3000 right now. The CW-5000 is nice but I can't swallow $700 at this point. Any other suggestions for getting the water temp down? I have considered a suggestion from a friend. He said to take a 5 gallon bucket and mount copper tubing in it. Then drop a frozen jug of water in it in the morning. It would require a but of plumbing and some maybe $100. Not sure I like the idea or not. I guess it wouldn't drop the temp too far. I'm assuming that lower is better until it reaches the freezing point and that would be impossible as my coolant is frozen water.

any thoughts or ideas other people have tried?

Check this out. this is what I use is an electronic controlled chiller CAMFIVE SL1 chiller.

Robert Walters
05-29-2014, 2:27 PM
In a previous post, someone suggested using a $100 water cooler from walmart:
walmart DOT com/ip/Primo-Hot-Cold-Water-Dispenser-White/23848191



Instead of a coil of copper tubing ($$$), just use a coil of plastic tubing.
You'll need more plastic tubing than copper tubing, but will be much cheaper too.
This is what many refrigerators do for "water in the door" as a reservoir.

Instead of a block of ice, fill 2L soda bottles with (distilled?) water, freeze them, and place one in your bucket.
When it's no longer frozen, toss it back in the freezer and grab another one to put in the bucket.
Then no city water will mix with your distilled water, and a nice little backup in case your chiller dies on ya.

Use one of those $20 digital cooking thermometers (walmart, amazon) that have
Hi/Lo temp alarms so you know when the water temp is too high.

If you want to save your laser at all costs in case of overheating, you could use a temperature controller;
northernbrewer DOT com/shop/johnson-controls-a419-digital-temp-controller.html

If you want an OVERTEMP idiot light, you could use a thermal switch:

If you get/use a fixed temp thermal switch, we would silicone (RTV) them to what we were protecting.
If you had to take it off, just use a razor blade. You could just silicone it to your laser tube directly, then as you replace the tube, you replace the switch as well.

This is more of a fancy one, but clips right on to a 1" pipe:
senasys DOT com/shop/products-page/thermostatssnapdisc/2570-34-sealed/1-inch-diameter-pipe-mount/2570f211/

If you use two of them (at different temps), you could have a WARNING light and a SHUTDOWN circuit.

If I had a water cooled laser, how do I know there's enough water in the bucket? the pump isn't defective? a line hasn't come off?

Liquid flow sensor
adafruit DOT com/products/828

That particular one isn't perfect, but cheap enough at $10 to play around with.
I'd wire it to an idiot light AND prevent the laser from firing if water isn't flowing or not flowing fast enough.

You could even get an Ardunio Nano off ebay for $6 shipped if you want the digital control.

Adrian Page
05-29-2014, 9:43 PM
Years ago I built a wood drying kiln. I used a dehumidifier as a heat source and to remove the water. The kiln itself was a box made of 2" styrofoam built over the stickered pile of wood. I just pressed big nails though the foam sheets to hold them together. The dehumidifier supplied plenty of heat to dry a pile of pine about 12 x 3 x 3 feet. Not really related to chilling a laser except to say, "Yeah... they throw off a pile of heat."

A window ac unit can sit in a window and blow all its heat outside in the summer without much effort.;) In the winter... maybe just vent it inside the shop. Walt has a great setup with his. I have yet to see any other device give more btu "bang for your buck" than a window ac unit.

Adrian

Adrian Page
05-30-2014, 8:38 AM
A dehumidifier is basically a window AC sort of unit with different packaging, reconfigured airflow, and condensate management (bucket and/or hose), for a higher price than similar cooling capacity AC unit.

Yup. And you can't just aim it at the CW3000 and have anything useful happen.

Adrian

Clark Pace
05-30-2014, 10:49 AM
Requres less electricity, but only works well in dry climates.
A dehumidifier is basically a window AC sort of unit with different packaging, reconfigured airflow, and condensate management (bucket and/or hose), for a higher price than similar cooling capacity AC unit.

Kev Williams
05-30-2014, 12:25 PM
AC's, heat pumps and dehumidifiers all work exactly the same way:

Refrigerant is pressurized, heating it. The heat is transferred to the cooling fins of the condenser, which must be cooled by fan.
This is the heat pump side--

It passes thru an expansion valve then to the evaporator, where the refrigerant and evaporator fins become extremely cold.
Water in the air condenses onto the cold evaporator, which goes into a drip pan, this is the dehumidifier side--
Air blown past the evaporator fins is cooled, this is the AC side...

SO- point the hot air inside and cold air outside and you have a heat pump.
Change direction and it's an AC unit.
Blow both the hot and cold air outside and it's strictly a dehumidifier.

So what happens if you just set a small AC unit in a room? The net effect is near zero, since the heat and cold generated cancel each other out, and the condensation collected just evaporates into the room.

Now, put the AC unit and a 3000 chiller in an enclosed but vented box with the hot air blowing outside the box, and that 3000 will keep the water all kinds of cool. Find the sweet spot on the AC thermostat, and you should be able to set it and forget it...

David Somers
05-30-2014, 12:53 PM
Kev,

You were saying that if you just set a window unit in a room, presumably with no ventillation, there is no net change in the room temp? Essentially the amount of heat removed from the air is the same as the heat exhausted and there is very little net heat gain? I have to respectfully disagree if that is what you meant. Even a decently efficient AC unit produces a lot of extra heat in the process of running. The energy used to run the compressor and fan is producing significant heat which is added to the room if you are not venting to the outside. Venting is important for any AC unit of this style. You are using energy to do work and that produces heat in the process. Our motors and related systems are still very inefficient in that regard.

This is not part of what you are referring to, but another overlooked aspect of AC units is that when they are vented to the outside you are creating a mild vacuum inside the room. If you blow air out then the air pressure in the room is going down in relationship to the outside air and adjacent rooms. So that outside air, which is warmer, will flow into the room and the AC unit must then transfer that heat out of the room as well.

Dave

Glen Monaghan
05-30-2014, 1:58 PM
Blow both the hot and cold air outside and it's strictly a dehumidifier.

You said that wrong... Blow both the hot and cold air INSIDE and it's strictly a dehumidifier. (Both the evaporator and condenser are inside, nothing is outside the conditioned space. A bit simplified, since a dehumidifier is configured differently than an AC unit... The AC unit has 2 separate air flows, one flow indoors over the evaporator and one flow outdoors over the condenser, while a dehumidifier has a single airflow passing from evaporator [to cool the air and condense moisture] to the condenser [to rewarm the air and further lower relative humidity].)



So what happens if you just set a small AC unit in a room? The net effect is near zero, since the heat and cold generated cancel each other out, and the condensation collected just evaporates into the room.

In a perfect world, yes. In the real world, not so. There is no generation of cold. Heat (energy) is just moved from one place to another. To that extent, the loss of heat in one place offsets the gain of heat in another. However, it takes additional energy (provided by the power grid) to move that heat around, and that additional energy is dissipated in the motor, pump, plumbing (friction of fluid flow), etc., adding heat to the system/space. So the room will get warmer. That's why running a dehumidifier actually makes a room warmer (fortunately, though, the lowered humidity makes the increased temperature more comfortable).

And, as for the condensation, whether it evaporates back into the room depends on what is done with it. With a dehumidifier installation, the condensate is collected in a bucket or sent by a hose down a drain. In a normal AC installation, the condensate has a path to drain out. If you just operate it completely inside a room, the condensate would just drain onto the floor (and eventually evaporate) unless you add your own collection bucket or drain hose (essentially converting the AC unit into a less effective dehumidifier).

David Somers
05-30-2014, 2:12 PM
Kev,

To add to Glen and my comments a bit.

If you have central AC where the AC unit is located outside the house completely and what you have inside is a simple fan for blowing cold air you can figure on about 5% of your BTU capacity for the unit being extra heat generated by the unit itself inside the house by the fan.

If you have a window mounted AC unit, the newer types are pretty good about keeping the condenser and fan outside of the room space and they will be roughly 5 to 10% of the BTU capacity being put into the room as heat, mostly by the fan.

If you have a "portable" AC unit where the entire unit is located inside the room with a simple hose carrying the waste heat and condensated water out a window then the heat gain in the room from the condenser and fan is upwards of 30% of your BTU capacity.

And in your example, presumably if you just plopped what is supposed to be a window mounted AC unit onto the floor and aimed it at your chiller, the heat gain from the condenser and fan being entirely in the room with no outside venting would be at least 30%. Pretty significant.

By the way, I dug those numbers up from Home Depot stats comparing AC units, their installation methods and differences in efficiency, and also from a general web site on AC use. They both agreed on the general numbers.

Hope that helps.

The idea is great. The key is to vent any unit to the outside, including the condensate.

Dave

Ray Beaty
05-31-2014, 1:33 PM
I built a room inside my workshop for my laser and am going to put an AC unit in it. My question is, can i put the ac with the exhaust facing inside the shop or does it need to face outside the shop? Hope this makes since.

Robert Walters
05-31-2014, 4:02 PM
I built a room inside my workshop for my laser and am going to put an AC unit in it. My question is, can i put the ac with the exhaust facing inside the shop or does it need to face outside the shop? Hope this makes since.

The part of a window air conditioner that would normally be on the outside of a window, will exhaust hot air.

If you built a room inside a room, and that "exterior" AC exhaust is mounted on an interior wall, then hot air will heat up the outer room.

I guess what you are asking is if you can get away with not cutting a hole in an exterior wall, and I'd say no.

But...

If you happen to have an attic or crawls space in the ceiling, you could "ceiling mount" it facing down, then basically "exhaust" it into the crawl space.

Ray Beaty
05-31-2014, 4:38 PM
The air conditioner exhaust will vent into the shop area so I don't care if it gets hot in the shop, just don't know if it has to exhaust to the outside?

Robert Walters
05-31-2014, 4:43 PM
The air conditioner exhaust will vent into the shop area so I don't care if it gets hot in the shop, just don't know if it has to exhaust to the outside?

It's just hot air (and maybe some water drainage due to condensation), nothing toxic about it if that's what you're asking.

Adrian Page
06-11-2014, 11:48 PM
In the winter, vent it inside. In the summer, vent it outside. (In Canada at least)

Adrian