Swamp cooler/ ice chest air conditioning

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XERTYX

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Well the sun has returned finally. All the little critters will soon start doing their thing and the world will be reborn.

That means hot weather isnt far behind. I did ok last year. Took a lot of showers to cut through the funky smell though. I sweat profusely in the summertime. Hows about something to take the edge off the heat?

Seeing as injecting ice water into my veins isnt an option I'll need some form of air conditioning. Traditional AC uses too much power. Also I get too reliant on it and never go outside. Opting rather to hang sides of beef next to me in my walk in freezer/bedroom.

Alternatives:

Box fans are my usual go to.

Misting sprayers would be nice for outdoors but use too much water.
 
Traveling to a cooler climate isnt a choice.

That leaves 2 options the way I see it.
A swamp cooler. That is a piece of damp breathable  sponge with a fan running to pull cooler air thru. 

Or an ice chest AC. A cooler filled with ice having 3 holes cut in the top. 1 for a fan to force air in and 2 pipes for the cooled air to come out.

I've never tried building one of these before but I've seen examples of both on YouTube before.

Swamp coolers I'm told work best in very dry climates like deserts. They evaporate the water in the sponge into the air cooling it in the process. Humid air is already saturated with water so is less efficient. 


The ice chest ACs tend to use a lot of ice I've heard. I'm planning to buy a portable ice maker this week so that might be doable. Also less tricky than rigging a small water fountain pump to the swamp cooler to automate rewetting the sponge.

So. Anyone tried these methods?
 
if you are worried about water, using a swamp cooler ain't going to help. a mister nozzle uses about 1/2 gallon an hour. a swamp cooler uses much more. highdesertranger
 
Neither of those will work very well. Swamp coolers use a LOT of water, and ice fans use a LOT of ice. They will be logistical nightmares.

Some math ... One pint of water will, as it evaporates, extract roughly 1000 BTU of heat energy from the surrounding air. So in order to get the same cooling effect from an evaporative cooler as from a small 2500 BTU portable air conditioner, you would need to evaporate around 2.5 pints per hour. This comes to 20 pints for each 8-hour period--roughly 2.5 gallons of water. For cooling equivalent to a typical small window AC unit of 5000 BTUs, double those figures--you would need to evaporate about 5 pints per hour, or roughly 5 gallons of water a day.

Some more math.... As a pound of ice melts, it absorbs roughly 150 BTUs of heat energy from the surrounding air. A common size of small portable air conditioner that can be run in a van from a generator or shore power is around 2500 BTUs. That means if you want to get the same cooling energy from an ice fan, you need to be able to melt 16.7 pounds of ice per hour, which would require roughly 128 pounds of ice for each eight-hour period. For cooling equivalent to a typical small window AC unit of 5000 BTU, double those figures--you'd need almost 34 pounds of ice per hour, or roughly 250 pounds per day.
 
Hmm. Good math. I did mention I just wanna take the edge off. Not achieve the same effect as a real air conditioner. Is that feasible?

I didnt know a swamp cooler would use quite that much water. Water isnt a huge huge concern for this purpose as it's a stationary off grid application atm.

I might try and use a mister for testing purposes with my pressurized water experiment in the hygiene thread. My main "chill zone" (yes a double entendre) is near where I have my garden every spring. I'm sure the veg wouldnt mind a little moisture in the air outside. I'll just continue the box fan indoors.
 
I don't know where you are but I find if put the mister in front of a fan it works really well, just point it at you . of course this is for an outdoor set up, in a low humidity environment. as it is no good indoors because it raises the humidity to much and evaporative coolers don't work in high humidity. highdesertranger
 
Or there's the method used by our ancestors: toughing it out.

:D
 
highdesertranger said:
 I find if put the mister in front of a fan it works really well,  just point it at you 

My version is to soak a t-shirt, put it on, then aim a fan right at me. It's a more efficient version of a swamp cooler. 

My preferred option to beat the heat, though, is to go north where it's cooler.  :)
 
lenny flank said:
My version is to soak a t-shirt, put it on, then aim a fan right at me.

A wet head rag is good too.
 
I been using swampcoolers for 6 years, they will take the edge off the heat. Water comsumption depends on how hot/humid its outside. Last weekend I used 2 liters of water over 2 days running it during the hottest part of the day. On a very hot weekend, I can go through 6 liters of water over both days. At night time water comsumption is almost zero, It has to be a very humid night for me to run all night long. These are real consumption usage rates from years of use, I never use more than 4 liters in one day even on some of the giant swampcoolers I built. 

To me the water comsumption isn't a big deal for the comfort I get. I like to spend all day in my van on the weekends parked in the sun to feed the solar panel. Without the swampcooler, I couldn't do it, if I turn the swampcooler off it gets uncomfortable real quick. I always carry extra fans and water pumps in case I have to make an emergency repair. I also have roof vent fans and a endless breeze fantastic fan, both are useless on a hot day. Even on a humid day the swampcooler will take the edge off the heat, they do work in humid conditions, just not as well as in drier climates.

For best results you need a well insulated vehicule, insulation will keep the heat out and make the swampcooler job easier. You need to vent the swampcooler to the outside, those who have bad experience with a swampcooler probably didnt vent properly. Do it right and its almost as good as AC, even with 2 powerful fans you might use less than 3 amps during use, even one lead acid and a small solar panel will run it.  

They are easy to build, you won't know if they work for you unless you try one. I run mine almost year round, just a few days in the winter where it was too cold to use. If you build one, keep the water tank area separated with a bulkhead from the fan area, that way you can drive without draining the water from the swampcooler. If you don't keep them separated water will slosh around and get all over your floor. It becomes a hassle having to drain the swampcooler everytime you need to drive. I wouldnt build one of the popular bucket designs, they just to hard to vent to the outside. 

small swampcooler
celdek small.jpg

outside vents for swampcooler
side vents.jpg
 

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I suppose there are build plans available if I flex my Google-Fu? I figured I would kinda design my own but as you've built many yourself is there a plan you followed? It looks like you put the fans inside container pointed outward. Is the water then on the opposite side? The one I saw briefly in an off grid tiny home tour video seemed to be a sponge with a water pump keeping it damp and air was forced thru it from the outside. It wasnt the focus of the video just sort of shown in passing.
 
Use a cooler woth block ice & the inlet & outlet holes in the lid so you can plug them & use as a cooler a small fan 12v, 120v or solar with a small panel run outside would be best.
 
lenny flank
“Neither of those will work very well. Swamp coolers use a LOT of water... 

Some math ... One pint of water will, as it evaporates, extract roughly 1000 BTU of heat energy from the surrounding air. So in order to get the same cooling effect from an evaporative cooler as from a small 2500 BTU portable air conditioner, you would need to evaporate around 2.5 pints per hour. This comes to 20 pints for each 8-hour period--roughly 2.5 gallons of water. For cooling equivalent to a typical small window AC unit of 5000 BTUs, double those figures--you would need to evaporate about 5 pints per hour, or roughly 5 gallons of water a day.

If 2.5 gallons for 8 hours of cooling is A LOT of water, you need to change your perception. 

For Burning Man 2018, I drove a small sedan, and decided if I’m going to have to tent it, Im going to be as comfortable as I can be inside it. So I brought a 5 gallon bucket cooler and ended up running it 12 hours a day, and ducted through 4” flexible vinyl duct so It spot cooled me under the sheets in a dark blue colored tent. The fan in the twin bucket stack cooler (pad in top, water in bottom) was a 4” marine bilge blower powered by about 120 pounds of batteries which were fully charged prior to leaving. 

Even if someone planted a device that changed the laws of physics inside the swamp cooler and it suddenly needed 60 gallons for the same cooling as 20 gallons used to do, and I had to pay $1 a gallon for the water I still consider it a worthwhile trade to not be miserable, getting a few hours of poor sleep while salty and clammy, and being able to actually enjoy my time in Black Rock City because I had a bubble of cool air to retreat to. 

Using the bigger number you calculated, 5 gallons a day X 14 days is 70 gallons, which is 10 reliance 7 gallon water containers of water, which take up a footprint of 10 square feet on a van floor. Even if you had to pay 25 cents a gallon for all 70 gallons of water, that is $17.50 to keep cool in the desert for 2 weeks. If you can’t carry Seven gallons at a time, you will need 14 Five gallon plastic jerry cans which will have a footprint of about 2.5x4.5 feet. If you rig is anything less than a minivan you will need to prioritize, you will need to decide if being this cool is worth the overhead in space and strain on a small car. If your rig is a regular cab van this amount of space is doable depending on your layout. When you arrive at your spot you put the containers outside. On the return trip these containers should be empty, and you’ll be able to tie them to the exterior of the van, if you’re concerned about the few percent increase in wind resistance of having them strung on the  roof - string them to the back. 

You will need to haul this water to your spot, and it will weigh in at about 560 pounds. Don’t feel like you’re overloading your CARGO van, even if it’s an extended cab van built to be a micro-roadtrek - the van is designed to haul this load all day everyday! 

Evaporative cooling works really well if you allow yourself the water! Less than $20 to stay cool for 2 weeks of Vandweller boondocking in the desert, and that’s if you pay for the water. 

The water containers are the most expensive part of this equation. 
 
I got a swamp cooler. In live in PA where it's moderately humid. I love this thing. Don't regret the hefty price tag
 
debit.servus said:
lenny flank
“Neither of those will work very well. Swamp coolers use a LOT of water... 

Some math ... One pint of water will, as it evaporates, extract roughly 1000 BTU of heat energy from the surrounding air. So in order to get the same cooling effect from an evaporative cooler as from a small 2500 BTU portable air conditioner, you would need to evaporate around 2.5 pints per hour. This comes to 20 pints for each 8-hour period--roughly 2.5 gallons of water. For cooling equivalent to a typical small window AC unit of 5000 BTUs, double those figures--you would need to evaporate about 5 pints per hour, or roughly 5 gallons of water a day.

If 2.5 gallons for 8 hours of cooling is A LOT of water, you need to change your perception. 

For Burning Man 2018, I drove a small sedan, and decided if I’m going to have to tent it, Im going to be as comfortable as I can be inside it. So I brought a 5 gallon bucket cooler and ended up running it 12 hours a day, and ducted through 4” flexible vinyl duct so It spot cooled me under the sheets in a dark blue colored tent. The fan in the twin bucket stack cooler (pad in top, water in bottom) was a 4” marine bilge blower powered by about 120 pounds of batteries which were fully charged prior to leaving. 

Even if someone planted a device that changed the laws of physics inside the swamp cooler and it suddenly needed 60 gallons for the same cooling as 20 gallons used to do, and I had to pay $1 a gallon for the water I still consider it a worthwhile trade to not be miserable, getting a few hours of poor sleep while salty and clammy, and being able to actually enjoy my time in Black Rock City because I had a bubble of cool air to retreat to. 

Using the bigger number you calculated, 5 gallons a day X 14 days is 70 gallons, which is 10 reliance 7 gallon water containers of water, which take up a footprint of 10 square feet on a van floor. Even if you had to pay 25 cents a gallon for all 70 gallons of water, that is $17.50 to keep cool in the desert for 2 weeks. If you can’t carry Seven gallons at a time, you will need 14 Five gallon plastic jerry cans which will have a footprint of about 2.5x4.5 feet. If you rig is anything less than a minivan you will need to prioritize, you will need to decide if being this cool is worth the overhead in space and strain on a small car. If your rig is a regular cab van this amount of space is doable depending on your layout. When you arrive at your spot you put the containers outside. On the return trip these containers should be empty, and you’ll be able to tie them to the exterior of the van, if you’re concerned about the few percent increase in wind resistance of having them strung on the  roof - string them to the back. 

You will need to haul this water to your spot, and it will weigh in at about 560 pounds. Don’t feel like you’re overloading your CARGO van, even if it’s an extended cab van built to be a micro-roadtrek - the van is designed to haul this load all day everyday! 

Evaporative cooling works really well if you allow yourself the water! Less than $20 to stay cool for 2 weeks of Vandweller boondocking in the desert, and that’s if you pay for the water. 

The water containers are the most expensive part of this equation. 

i dont use 5 gallons of water a week, total! i carry 2each 7 gallon jugs and a couple 1 gallon jugs for about 16 gallons. no way i am giving up all the extra space and weight need to carry 70 gallons of extra water just to try and keep cool. i move around exploring too much to mes with all that. my 1000 watt honda will run a 5000 btu window air conditioner all day on less than a gallon of gas. 70 gallons of gas would weigh in about 150 pounds less than all that water and keep me truly cool for a couple months and it will work independent of how humid it is. of course the truth be told, if i was really going to be somewhere i need the cooling i would just load up the roof with a few solar panels and run a window unit during the day. if that didnt keep me happy i would move to a cooler location.
 
I use a spray bottle on mist as I sit in front of a fan. I'm usually as nude as the situation allows, so that helps with the water mist evaporating\cooling. It's cheap and doesn't kill my water supply.
 
if it's that hot at night why are you there? I would move. if it's that hot during the day, what are you doing inside? I don't understand the being inside all day thing. if for some reason I had to be inside all day, I would move to where it's not so hot.

during the hot part of the year I usually take a break during the hot part of the day. I set my lounge chair up in the shade eat a light lunch and read a book which means I usually end up taking a siesta.

no water, no batteries, no generator, no gas, and no ice.

highdesertranger
 
^^^^ Yep. Make like the birdies---north (or uphill) in summer, south (or downhill) in winter.

I have no insulation, no heater, no AC, no ice, no cooling water, and no need.
 
I built one of those ice coolers using a 12 volt blower and a ice chest. Probably have $50 in it but you can have it for free. Currently in Parker AZ till May 8 and then north to Flagstaff area

It's more expensive to check into a RV park but I can run my air conditioner and it's less work.
 

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