in 2011 I built a Tear drop trailer (TD) similar to this http://www.instructables.com/id/Teardrop-Travel-Trailer/ , most TD campers carry some sort of air conditioner to deal with the hot weather. In dry areas of the country a swamp cooler works fine as blowing a fan over a block of ice will cool the air and any moisture picked up from the ice will feel nice.
In humid areas of the country a swamp cooler just adds to the misery, I remember spending a few weeks in Mena, AR at a paint shop. At 97 F and 90% humidity the sanding crew was dying from the heat in the shade, so the boss went out and borrowed or rented a swamp cooler. As I was just observing our aircraft being painted I could sit right in front of the swamp cooler all day, from walking around I discovered that the cooler feeling air only lasted about 4-6 feet from the cooler, after that the breeze felt ok and more than 10 feet away all you got was the noise of the huge fan.
The swamp cooler was about 6 feet square, it had a 5 foot tall fan blowing through some sort of paper strips that were being saturated with water being pumped over them from a large tank in the base. the base tank needed to be hooked to a garden hose to keep it from going dry. For all the water being evaporated I think the swamp cooler just made it worse inside the paint shop, and it made the paint jobs have problems.
the main reason air conditioning feels so nice in humid areas is that the air conditioner removes quite a bit of water vapor, dry air allows you to sweat, which is the way your skin gets rid of extra heat. Just look underneath your car or air conditioner and you will see a puddle on a hot humid day. In fact modern cars run the air conditioner on low when you select "defrost" to remove the excess moisture.
For those of us who don't want to lug an air conditioner in our trailers (or tents), and where a swamp cooler won't work, or where you would need a 50 mile extension cord or deal with a generator, I took a few different ideas from Instructables.com and put them together in my car.
Being from Maine, I bought a new car without air conditioning, since we only need AC for a week or two up here almost 25% of cars are sold without AC, saving about $800. Since then I got a job in central NH where the weather is much hotter than coastal Maine. I decided I needed some AC.
I bought a used heater core off of fleabay for $25, a cooler that would fit between my kids booster seats in the back seat $35, two computer cooling fans for $15 fleabay, and a 12 volt live bait well pump $30 wallyworld boating isle. When assembled as shown the heater core blew cold air on the back of my head, but was not enough to cool off my car with it's untinted windows and blazing sun shinning in. I also thought my heater core was garbage as water streamed from it while it was running, after pressure checking it I found it was still good, I had been condensing tons of water out of the humid air.
While this was a failure, I learned a few things, that if applied to a well insulated area (inside my TD which if you made it a cube would only be 160 cubic feet (5' W X 8' L X 4' H)) will work as long as enough ice is used.
I modified my "air conditioner" into a "body cooler" and now it works great, and the ice lasts forever.
In humid areas of the country a swamp cooler just adds to the misery, I remember spending a few weeks in Mena, AR at a paint shop. At 97 F and 90% humidity the sanding crew was dying from the heat in the shade, so the boss went out and borrowed or rented a swamp cooler. As I was just observing our aircraft being painted I could sit right in front of the swamp cooler all day, from walking around I discovered that the cooler feeling air only lasted about 4-6 feet from the cooler, after that the breeze felt ok and more than 10 feet away all you got was the noise of the huge fan.
The swamp cooler was about 6 feet square, it had a 5 foot tall fan blowing through some sort of paper strips that were being saturated with water being pumped over them from a large tank in the base. the base tank needed to be hooked to a garden hose to keep it from going dry. For all the water being evaporated I think the swamp cooler just made it worse inside the paint shop, and it made the paint jobs have problems.
the main reason air conditioning feels so nice in humid areas is that the air conditioner removes quite a bit of water vapor, dry air allows you to sweat, which is the way your skin gets rid of extra heat. Just look underneath your car or air conditioner and you will see a puddle on a hot humid day. In fact modern cars run the air conditioner on low when you select "defrost" to remove the excess moisture.
For those of us who don't want to lug an air conditioner in our trailers (or tents), and where a swamp cooler won't work, or where you would need a 50 mile extension cord or deal with a generator, I took a few different ideas from Instructables.com and put them together in my car.
Being from Maine, I bought a new car without air conditioning, since we only need AC for a week or two up here almost 25% of cars are sold without AC, saving about $800. Since then I got a job in central NH where the weather is much hotter than coastal Maine. I decided I needed some AC.
I bought a used heater core off of fleabay for $25, a cooler that would fit between my kids booster seats in the back seat $35, two computer cooling fans for $15 fleabay, and a 12 volt live bait well pump $30 wallyworld boating isle. When assembled as shown the heater core blew cold air on the back of my head, but was not enough to cool off my car with it's untinted windows and blazing sun shinning in. I also thought my heater core was garbage as water streamed from it while it was running, after pressure checking it I found it was still good, I had been condensing tons of water out of the humid air.
While this was a failure, I learned a few things, that if applied to a well insulated area (inside my TD which if you made it a cube would only be 160 cubic feet (5' W X 8' L X 4' H)) will work as long as enough ice is used.
I modified my "air conditioner" into a "body cooler" and now it works great, and the ice lasts forever.
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to build a 12 volt air conditioner or body cooler you will need mostly the same items..
-flexible hose and clamps
-12 volt bait well pump (I bought the 500 gph model, way over kill on the flow rate but cheap)
-wiring
-cigar lighter plug
-largest cooler you can fit in the area it will sit. (air conditioners are rated in BTU's, the smallest ones for sale cheap are the 5,000 BTU ones, house and larger ones are rated in tons, this air conditioner will depend on how much ice you can put in it) I found the "marine" coolers the best for what I needed as they tend to be all white (less solar heat gain) and much more rectangular with less bulk (takes up space) mine also has large easy to hold handles (easy to strap into the seat belt in the car, and easy to carry full of ice and water) it also has an external hinge, most hinged lid designs have a air leak around the hinge, the external hinge type have a lid that will lock in place even if you remove the hinges.
-zip ties
for a 12 volt air conditioner you will also need:
-a car heater core (mine was from a jeep Cherokee, I figured one from an SUV or van would have a larger heat exchanging area than one for a small car)
-as many 12 volt fans as it will take to cover the grid section of the heater core.
-12 volt switches or a house thermostat (if you want the fan to go on and off at a certain temp)
-a drip pan that is larger than the heater core and some sort of drain line to carry condensation back to the cooler
for a body cooler:
-small diameter PEX plumbing and fittings (I used 3/8" but now I see 1/4" in some hardware stores)
Tools:
drill and hole drills
screw drivers
wire crimpers
pex ring crimpers (if you use pex) (my crimper is a two part C shaped set of jaws that you squeeze using vice grips, it has spots in it to crimp 3/8", 1/2", 3/4", and 1" pex copper crimp rings.
-flexible hose and clamps
-12 volt bait well pump (I bought the 500 gph model, way over kill on the flow rate but cheap)
-wiring
-cigar lighter plug
-largest cooler you can fit in the area it will sit. (air conditioners are rated in BTU's, the smallest ones for sale cheap are the 5,000 BTU ones, house and larger ones are rated in tons, this air conditioner will depend on how much ice you can put in it) I found the "marine" coolers the best for what I needed as they tend to be all white (less solar heat gain) and much more rectangular with less bulk (takes up space) mine also has large easy to hold handles (easy to strap into the seat belt in the car, and easy to carry full of ice and water) it also has an external hinge, most hinged lid designs have a air leak around the hinge, the external hinge type have a lid that will lock in place even if you remove the hinges.
-zip ties
for a 12 volt air conditioner you will also need:
-a car heater core (mine was from a jeep Cherokee, I figured one from an SUV or van would have a larger heat exchanging area than one for a small car)
-as many 12 volt fans as it will take to cover the grid section of the heater core.
-12 volt switches or a house thermostat (if you want the fan to go on and off at a certain temp)
-a drip pan that is larger than the heater core and some sort of drain line to carry condensation back to the cooler
for a body cooler:
-small diameter PEX plumbing and fittings (I used 3/8" but now I see 1/4" in some hardware stores)
Tools:
drill and hole drills
screw drivers
wire crimpers
pex ring crimpers (if you use pex) (my crimper is a two part C shaped set of jaws that you squeeze using vice grips, it has spots in it to crimp 3/8", 1/2", 3/4", and 1" pex copper crimp rings.
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More ice, more surface area, and one strong fan will deliver ICE COLD air..but it won't last very long at all. How do I know this? I am glad you asked, please allow me to explain,
Having access to all kinds of motorcycle/ATV/Jet Ski stuff as well numerous race and project car parts allowed me to build one kick-a** swamp cooler.. I used a Ron Davis aluminum racing radiator (designed for a small block chevy.dropped in a 1st gen RX-7), a 12 V electric bilge pump, and an older KX60 radiator and dropped all this in a HUGE styrofoam cooler courtesy of one very large Omaha Steaks order. I took a knife and cut out two holes in the lid, used a cut up water hose to pipe the water into and out of the cooler. A trip to Lowes provided an adapter that allowed me to step up (and down) from water hose size to car radiator hose size. I froze several half gallon (organic as they tend to be thicker in construction) milk cartons full of water. Then I stopped by the ice trailer and dumped in 20lbs of crushed ice...
I happened to have a couple of Suzuki GSXR motorcycle (12V ) fans, so I used the existing shroud brackets to mount the behind the big radiator. pushing air through it.. hopefully COLD air..
sooooooo with all this ice, one big aluminum radiator, a very high flow pump, and a small radiator resting below iceberg, and two sportbike fans, I only needed 12 volts. I used a battery charger for juice and hooked that sucker up.. WOW!! I had COLD AIR!! It was great!! It was awesome..it felt so good. Then in approximately thirty two minutes the air was no longer ice cold.. then in a few minutes it wasn't cold at all.. a few moments more it was warm...
Sooooo all that being said - you are onto something but it isn't very efficient.. but sometimes, WHO CARES!?!? When it's a hundred degrees who cares about that - all that matters is there is some cold air - albeit briefly.
http://simegen.com/writers/lois/pykrete.htm
Swamp coolers, though cheap, are highly energy intensive, and roughly 1/4 as efficient at cooling air as a car pump or home heat pump.
This design uses the very cold heater core to chill the air, as you know a cold glass of water with ice cubes in it will get condensation on the out side of the glass, the excess water vapor condenses on the heater core. From my own testing I found the water vapor condensing was enough to make me think my heater core was leaking.
the whole point of the is I'ble was to make a portable "air conditioner" or a body cooler, the air conditioner will only really work in a small area with good insulation. The body cooler will work anywhere you can carry a cooler of ice since it doesn't take that much surface area to extract a good deal of heat from your blood.
There are much better ways that don't rely on outside energy sources to cool a stationary area, the best being an underground tunnel, the ground is
a rather constant 45 F. I have read of homes in the middle east using an underground tunnel to chill incoming air. With a wind catching funnel on the roof to pull the air up a big enough tunnel would work.
Underground homes built into the side of a hill are about the most energy efficient as they only have to heat or cool from 45 degrees or so, make the side open to the air face south in the norther hemisphere or north in the southern hemisphere and you can rely on solar for much of the heating.
The next best design being to build a house within a house, you have an outer shell that is insulated, then an air gap and an inner house that is insulated, the windows and doors are connected through "tunnels". The basement air is allowed to circulate through the air gap freely and up into the attic, that way the air envelope around the house will be mostly at ground temp and you only have to heat or cool the inner house from the ground temp.
This I'ble won't work for a house, it may work for a small room like a dorm room.
To create blocks of ice, you have to use some kind of exchanger, either a heat pump, a gas absorption set up or a standard compressor-condessor-evaporator. Those objects still create heat. Imagine if you will a refrigerator cooling water to make blocks of ice for the "personal air conditioner". That refrigerator is using the compression and expansion of gases to create a cold environment. But it pumps the heat right back into the room that's being cooled.
The device in this instructable exchanges air with chilled water. The biproduct is warm water, which is of course pumped BACK into the cooler full of ice. This speeds up the melting process and eventually you're left with a cooler full of warm water. The fan motors create heat. The friction of the fan blades creates heat, the coolant pump creates, you guessed it, heat. The system is only capable of producing momentary personal comfort on an energy scale that is not feasible. All told, the heat from the fridge, fan, pump and motors all have a greater thermal output than the ice's ability to cool. In a closed environment, eventually the thermal output would be so great the refrigerator wouldn't make ice anymore.
This I'ble could be used to cool a well insulated tent. The best design to keep a house cool in summer is to build underground.
I'm simply saying, you've created a highly energy intensive and thermally inefficient means of cooling a small space, one that could be mitigated by proper hydration and airflow. It's a comfort thing I suppose, not everybody needs ice cold air blowing at them.
I am only looking for 6-8 hours of colder, less humid air as that is all I would need to sleep in my TD.
The tntt.com member who tried this plans on a coil of copper tubing running through the ice rather than a bath of ice water, I don't know it there would be any increase in the time the ice would last or not.
this was never meant to cool a house, even the possibility of cooling a dorm room with it depends on the ice machine being outside the dorm room.
The "air conditioner" is only meant to be used a few nights a year for camping in my TD, on those rare nights (up here in new england) when it is just to hot to sleep comfortably, the body cooler got used almost every day last july, august and part of september. I keep the "ice bottles" in my deep freeze at home and the nearly empty freezer in the fridge at work.
Being from Maine I consider anything over 90 F way to hot, and thanks to radiant cooling we get only one or two nights a year that it doesn't drop to a comfortable temp at night. When I visit my inlaws in PA I can't sleep without some ac. Maybe you can get used to it and sleep with just a fan...
Myself I probably find ammonia interesting once I had my first camping trailer and learned how the Frig worked off a small flame or heat source.
Rowerwet do you have any mold/mildew problem on your heater core? I may have missed this in my browsing of this?
I have seen people do the math on multiple peltier set ups, the part that doesn't work on 12v portable power is the amperage draw. unless I had a large bank of batteries it just won't last that long. you end up needing a 12v generator, windmill or large solar panel, since I will be sleeping while using this I don't want a generator, high wind, and the sun won't be shining.
If multiple Peltier set ups ever break this power barrier I can see them going into cars to replace the Freon cycle ac, until then ...
IIRC there is one current hybrid car that uses these to help cool it using solar, but I may be wrong.
But you misunderstood me to mean that it be used alone; I meant for it to be used in a situation similar to the project these comments are attached to. Peltier modules gain in efficiency for cooling when their hot side is connected to a heat sink, such as the water reservoir in this project. It would lessen the heft of the evaporator section, simply forming another way to achieve the same end. I merely suggested it as an alternative way of doing the heat exchange. For a Peltier to be used effectively, it would need the heat sink and need a fan to help distribute the cooled air.
josh
I have read more than one story about the depression that mentioned an ammonia refrigerator, so I know they were around then.
Heat transport with compressing has been around more than hundred years then.
There have also been "phase change" systems around before Linde, which used other "low temp boiling" liquids.
The use of ammonia wasn't invented by Linde either, but he perfected the cooling machine to a commercial success.
This was then very important for the breweries.
Until then, they couldn't brew bottom fermented beers during the warmer months. (Although they dug caves and stored natural ice in there)
So during depression, they certainly could have had ammonia fridges, if they could afford it.
It brings out the crispness of lager beers.
For top fermented beers like ales, this cold phase isn't needed.
But for drinking, you might want to cool it anyway...
This seems like a neat idea, with good problem solving, but it seems misleading to call it an air conditioner. http://en.wikipedia.org/wiki/Air_conditioner
Finally, although Wikipedia is a fine source for looking up the basics of a term, it can also be wrong as well... try looking up the actual references.
I also can't understand how you could possibly miss the first sentence on your Wikipedia link which states "mechanism designed to dehumidify and extract heat from an area."... that is precisely what this unit is doing...
I hate to burst *your* bubble but, your complaint is null and void.
just like you call a tissue a kleenex, clear plastic tape scotch tape, or inline skates rollerblades.
the cooling could be done using ammonia/water or just about any gas, freon just works the best.
Dry ice or liquid nitrogen could be used to condition air also, they just add a ton of design issues.