AC unit made from ice cooler and portable fan.

[highdesertranger]

so let me take a shot at this. a radiator can not cool water below ambient air temp because there is no evaporation going on it's sealed. once the water reaches ambient temp the is no more cooling going on the air blowing across the radiator is the same as ambient. in fact running water though a radiator would raise the temp of the water faster than if not run tough a radiator. this is all basic physics and a simple experiment with a thermometer will prove it. off grid whoever told you that running water though a radiator would cool the water below the ambient temp is just plain wrong. a radiator will cool water down to ambient and no more. a radiator works in a car because you are taking water that's 200+ and bringing the temp down to closer to ambient temp. this is not evaporation but convection the water can never go below the ambient air temp because nothing is added or taken away to bring the temp down. with all due respect you are starting to sound like the global warming people. highdesertranger

 

[SoulRaven]

HDR, where are you located? If you're somewhere near my travels, I would be more than happy to come and prove your interpretation of physics wrong.

I guess all those thousands, maybe millions of swamp coolers they sold with the identical configuration, that cooled the houses of so many must have been an illusion if your physics says it's impossible.

According to your interpretation, that standing warm water in city reservoirs should be warm water when it reaches your house too, maybe even warmer. I guess the city must refrigerate it along the way...

Guess all those youtube videos by many different people, proving the system works must somehow be faked too. Major conspiracy I guess, if physics says it's impossible.

I'm sure glad that none of the great people who have improved the lives of mankind over the years believed in physics, because if they did, we'd still be living in caves in the stone age.

 

[IGBT]

LMAO

Water running from the reservoir to your house runs through a big radiator called Earth which usually is a lot cooler underground than the ambient air (or warmer if you are in a very cold climate).

The water in the reservoir could be 80 degrees and come into your house at 55 degrees because the buried pipes are running through dirt that is around 50 degrees.

 

[amwbox]

HDR, where are you located? If you're somewhere near my travels, I would be more than happy to come and prove your interpretation of physics wrong.

I guess all those thousands, maybe millions of swamp coolers they sold with the identical configuration, that cooled the houses of so many must have been an illusion if your physics says it's impossible.

According to your interpretation, that standing warm water in city reservoirs should be warm water when it reaches your house too, maybe even warmer. I guess the city must refrigerate it along the way...

Guess all those youtube videos by many different people, proving the system works must somehow be faked too. Major conspiracy I guess, if physics says it's impossible.

I'm sure glad that none of the great people who have improved the lives of mankind over the years believed in physics, because if they did, we'd still be living in caves in the stone age.

I don't think I've ever seen anyone claim that swamp coolers don't work. Far as I know they can lower temps by as much as 20 degrees if the conditions are right. To test that principle, all one needs do is hang up some wet towels on racks and blow air over them with a box fan. Will cool the room down no question...because of the evaporative effect. At least until the air becomes saturated and evaporation won't work so well anymore.

Maybe I'm misunderstanding...but what it sounds like you're describing is very different from that. It sounds like your saying blowing warm air through a radiator full of warm water will result in cool air coming out the other side.

Unless you keep adding ice...there is no physical way to make a constant amount of water stay cold when its in direct contact with something warmer than it is.

And for the record...the most basic laws of nature aren't really theoretical at all. They are mathematically verified, and have been for centuries. You can count on the laws of thermodynamics in exactly the same way you can count on water running downhill or warm air rising. Its just how the universe works, and its never failed. If it was so easy to prove scientific laws wrong that some guy with a tabletop cooler could do it...it would have been done long ago. Any cooling effect your getting from a cooler of any type, is happening squarely within the limits of these laws. You can also find dozens of youtube videos showing miraculous "free energy generators"...and down the very last example they are either hoaxes or simple errors.

"There ain't no such thing as a free lunch."

 

[coolmom42]

In an evaporative cooler, like a swamp cooler, the air blows over ambient temperature water.  The heat from the air is transferred to the water, by contact with the water.  The heat is used in the phase change process, when water changes from a liquid to a vapor.  That phase change requires energy of 2260 joules per gram of water evaporated.  I'm too lazy to do the math but it's enough to drop the air temp a lot.  The downside is that the change to water vapor increases the humidity of whatever enclosed space the cooler is in.

A similar cooler with ice works by the same heat transfer mechanism.  But in that case there are 2 phase changes-- solid to liquid and liquid to vapor.  Thus the block of ice can remove a more heat energy from the air than the same volume of water.

All that energy goes into the phase changes of the water, not into increasing the temperature of the water.

 

[amwbox]

In an evaporative cooler, like a swamp cooler, the air blows over ambient temperature water.  The heat from the air is transferred to the water, by contact with the water.  The heat is used in the phase change process, when water changes from a liquid to a vapor.  That phase change requires energy of 2260 joules per gram of water evaporated.  I'm too lazy to do the math but it's enough to drop the air temp a lot.  The downside is that the change to water vapor increases the humidity of whatever enclosed space the cooler is in.

A similar cooler with ice works by the same heat transfer mechanism.  But in that case there are 2 phase changes-- solid to liquid and liquid to vapor.  Thus the block of ice can remove a more heat energy from the air than the same volume of water.

All that energy goes into the phase changes of the water, not into increasing the temperature of the water.

That's correct. But we're talking about a set amount of water being circulated through a radiator. In that case its not actually evaporative cooling, but the difference in temperature between the ambient air and the water inside the radiator. The problem is that there's no explanation of how the water inside a loop stays cool with warmer air being continuously blown over it.

 

[ZoNiE]

The box unit that needed water to be drained from it was a cheap dehumidifier.

In a built in application, The radiator type is called a "chiller". Large buildings and apartment complexes used to be built with these. I lived in a few when I was young. In the summer, a very large compressor chills water in a chiller barrel, and pumps circulate it to the radiators in the units. A fan blows across this and the water extracts heat from the air much like an air conditioner. The water is basically a secondary refrigerant. In the winter, the water is heated in a boiler. One of the units failed one summer, and it took a month to get it replaced. The whole complex ran on the secondary smaller unit. Now they bring a portable one in on a trailer.

These were popular in the 70's but are falling out of favor. They don't dehumidify well. They actually sweat a lot with condnsation, and the pan always overflowed in monsoon season (high humidity) and sometimes water blew out. My apartment in central Phoenix was about 66* in the summer but humid. It always smelled musty. The closer you were to the cooling plant the cooler you could keep the place. Utilities were included in the rent, and this was a perfect setup for a 19 year old kid with a roommate. Only one bill to split. The whole shebang had a large cooling tower to expel the heat.

You can do this without a compressor, you need a large tank of water to act as a thermal mass, and you can use a cooling tower to radiate the heat out of the system. The cooling tower works sort of like an evap cooler for the water. I designed and built an industrial chiller for testing / repairing water cooled radio equipment with a 300 gallon water tank and it worked very well for about half the day, then the compressor kicked in to cool it down. I didn't use a cooling tower, the condensing unit was basically a swimming pool heat pump running in cooling mode.

 

[highdesertranger]

the chillers I have seen don't work like that. I am curious, how does the compressor chill the water. highdesertranger

 

[ZoNiE]

The chiller barrel is just a big tank of water that has freon lines running through it. It essentially acts as a heat exchanger. The Freon lines absorb heat from the water coming from the evaporators (radiators), then a normal refrigeration cycle expels the heat in a condensing unit which is sometimes in a cooling tower, sometimes not.

The water is cooled with a cooling tower. Water is pumped to the top of a big fan box and sprayed down. The fan draws air up through it and blows the heat out.

A considerable amount of water is lost to evaporation in the tower, so they consume a bit of water. They were very efficient, but waste water, and when the thing breaks, the whole place loses cooling.

They don't use 'em much anymore for residential as it basically is an industrial thing and individual packaged heat pumps are easier to maintain.

 

[SoulRaven]

Let me sum this up real simple and easy...

I might not know exactly why or how, my A/C works, nor do I really care.

To me life is much simpler than that. It either works or it doesn't. Simple as that.

Now when I have something that has worked for a number of years, and somebody want's to to tell me that physics or some other non-existent force says it doesn't or can't work. They are obviously the ones that are mistaken.

Before retirement, I was a truck driver for 20 years, and units similar to my home made unit were available at truck stops, in both the evaporative, and the radiator type models, depending on where you were. The workings are the same, they have been around for years, and have worked just fine for people for many years.

You can buy factory ones of these starting at about $500, or you can build one that is actually much more efficient for about $40. The choice is yours. Whether you choose to go with an evaporative swamp cooler type one, or the radiator style one, they are good choices for van dwellers, and THEY DO WORK, regardless of what the naysayers say. They also require very little power, hardly more than just a fan alone.

 

[Vantastic]

WOW...some of us can really overthink this.  What about dry ice
chunks laid wrapped in newspaper topped with cardboard?  Much
more expensive than a block of ice, but we can splurge now and then.

Bottom line...person is in van or whatnot w/no air and it is hot inside.
Cool air might not be doing what refrigerated air does ala a proper
A/C unit, but it does blow cold on you and that is good right for 5-6
hours?  No, that is VERY good!

Nothing worse than trying to sleep in the hot...I would love to have cool
air blowing at night to fall asleep in a hot van.  if a block of ice is available
and you are not so remote, and most van dwellers cannot have A/C, this
is a great alternative and a serious thread imo!

Measure twice, cut once!

 

[Vantastic]

(sorry, couldn't edit my post but thought of this)

If there was a single coil output hose to draw warn air out this would
solve a lot of the science concerned similar to a portable A/C unit
using conditioned air from the room to cool and exhaust the hot air out
an exhaust hose. This creates negative pressure causing unconditioned
warm air from surrounding rooms or outdoors to be drawn into the room
you’re trying keep cool. 

Yet, even those portable single coil hose units might drop the room temp
by 10 degrees...the dual coil fairing somewhat better.  My sister lives in a
town home with strict regulations--no wall A/C units so she bought an LG
portable.  Useless on the second story which feels like a van in the summertime!
At 90, after two hours on high dropped by 8-10 degrees (which is better than 90)
but not good enough for her weekend bed and breakfast occupants.

Back to a Bomb Pop on a hot summer day!

 

[SoulRaven]

Please don't use dry ice in a van, it off gasses some pretty nasty stuff, possibly even deadly.

Can't look it up right now, but I remember the warnings.