This instructable will show you how I converted a 240 volt rooftop Evaporative air conditioner to a Mobile unit run on my DIY 12 volt solar setup.
My setup supports the 2 most important things in the house.
The 12 volt Beer fridge and the Air Conditioner.
Without either of these the summers here would be unbearable.
There is also something quite satisfying about sitting in a cool house sipping icy cold beer on a stinking hot day knowing the sun has done all the cooling.
My setup supports the 2 most important things in the house.
The 12 volt Beer fridge and the Air Conditioner.
Without either of these the summers here would be unbearable.
There is also something quite satisfying about sitting in a cool house sipping icy cold beer on a stinking hot day knowing the sun has done all the cooling.
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Signing UpStep 1: The beginning.
First you need to obtain an old evap air cooler.
I bought mine on ebay for around $200. Winter is the cheapest time to buy one.
A trip to the local rubbish tip netted me an old BBQ on a stand with wheels at one end. I left the rusted out BBQ there and took the stand home.
A wooden pallet went with me.
The Air Cooler then had all the electrics, the huge 240 volt motor (unfortunately not permanent magnet) and the 240 volt pump unceremoniously ripped out (taking up space in my shed now if you want them).
It was then attached to the aforementioned pallet which was screwed to the top of the BBQ stand.
Now it's ready for step 2.
I bought mine on ebay for around $200. Winter is the cheapest time to buy one.
A trip to the local rubbish tip netted me an old BBQ on a stand with wheels at one end. I left the rusted out BBQ there and took the stand home.
A wooden pallet went with me.
The Air Cooler then had all the electrics, the huge 240 volt motor (unfortunately not permanent magnet) and the 240 volt pump unceremoniously ripped out (taking up space in my shed now if you want them).
It was then attached to the aforementioned pallet which was screwed to the top of the BBQ stand.
Now it's ready for step 2.
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There is a version of this which uses one more step that doesn't send moist air through your house. It sprays the water over the inward facing slats and then pumps it from the catch pan at the bottom through a heat exchanger through which air that is already in your house is circulated and blown back inside so that you don't have to cool hot outside air. moisture is in fact removed from the air in the house condensing on the cooler surface of the heat exchanger. This moisture (if any) is then routed to the catch pan reducing slightly the demand on municipal water. From the heat exchanger the water then flows to the spray nozzles over the inward facing slats of the enclosure and the process starts over again. everything else is the same as your setup, although using solar to run it is ingenious. Great Job!
I am not chemist so I cannot explain the ammonia. chlorine relationship but here:
http://en.wikipedia.org/wiki/Chloramine
Chlorine and ammonia? There's a warning on all ammonia containers to AVOID mixing with chlorine. That potentially produces deadly free chlorine gas, and several other deadly toxic poisons, depending on the ratio of bleach to ammonia. This article ought to scare the **** out of you.
http://h2g2.com/dna/h2g2/classic/A795611
Do a search for "ammonia chlorine" and see all the disasters listed. It's scary!
Other than your mention here, there is no other reference to "clormanated". Could you please check with your water supplier and let me/us know? Thanks in advance.
-o-
Evaporative coolers REQUIRE a free flow of air FROM OUTSIDE through the wet pads into the house and out open doors, windows, etc.
Some think this works like a refrigeration type air conditioner (it doesn't) and try to "keep the cool air inside" by closing doors and windows. All this does is make the house HOT and HUMID. To remove heat, you must evaporate water with free flowing air.
When you sweat, a fan blowing lots of air across your wet skin and wet clothing cools you. If you wrap up in a plastic rain coat, you will be VERY hot.
I rebuilt an old evap cooler (a large window mount with a 1/2 HP blower motor) and set it up in the back yard for testing. It was well over 110 degrees that day, with very low humidity. It literally cooled the entire back yard.
The less restricted the air flow, the more water it evaporates, and the cooler it gets.
It is a brilliant idea!
However, here in East Texas, we have pretty high humidity and the house would get 'wet' from using an evaporative cooler. In west Texas they are everywhere.
So, as an alternative, could this be used to cool the attic area of the house? Would this save enough on the main A/C unit to be worthwhile? Would it cause too much moisture in the attic?
Do you know where I might find the answer to these questions?
Thanks.
Thanks for your nice comment and question.
This type of cooler can be used effectively in areas that experience moderate to high humidity but you MUST allow the cooled air to flow THROUGH your house. At least one window or door needs to be left open to allow the cooled air to escape.
In effect what you are aiming to achieve is a cool breeze through your house.
Simply pumping the cooled air into a room would soon cause problems.
Your Attic.
Does your house have ceiling insulation?
If it does then cooling your attic area might not make a lot of difference.
If it does not then cooling that area and using ceiling fans inside your house would make a difference I'm sure.
Does the air in your attic area get "baked" ( and dried ) by the heat of the Sun?
If it does then it might be much lower in humidity and therefore more suitable as the air source for the Cooler. You might even be able to have your cooler mounted in the attic area and ducted directly through the ceiling.
Just a thought.
Cheers.
Rob.
Yes, our house has insulation between the ceiling and attic. However, all the central A/C ducting runs through the attic space. My feeling is that if the attic space had cool air coming in at the eaves and the hot air drafting out at the roof peaks, then this may lower the attic temperature, and then reduce the heating of the cool air ducts.
When I first began thinking of making solar panels to generate electricity, I was kind of at a loss for how to use this energy in a way that would help reduce our energy costs rather than just give me more ways to use free energy.
After reading your instructables I think that I might be able to use your idea to reduce our energy costs without the issues of tapping into the house electrical system.
Thanks. You have given me some good inspiration here.
Evaporative cooling has severe limits in humid areas. For example large buildings use chillers with water towers. The water towers use high horsepower fans and pumps to drop the water down through the towers. The idea being that evaporation will cool the water that makes it to the floor of the tower. That turns 95 degree air into 85 degree water. That water chills the hot side of a huge compressor so that large amounts of freon are not pumped through the building. The reason being that people could drown in freon in those quantities. The cold side of the freon loop is used to chill water down to about 52F and that cold water is pumped to coils in various rooms where fans behind the coils push air through them to cool the rooms.
That is the only use of evaporative cooling in humid areas that bears fruit at all. It is expensive beyond imagination and the water bills alone would break you.
The best bet is to get a central AC unit and replace it more often than you usually do. The rotary compressors are a good bet these days and a great energy rating is vital. The days of keeping an AC for 15 years are not with us anymore and decent AC units are expensive.
I'm not sure what your message is.
My instructable is not intended as a forum for discussing the virtues of one type of air cooling over another.
The message my instructable is intending to give is this:
We have the necessary skills to make a difference to both our lives and the environment if we try. And we can do it on a small budget.
A simple conversion from an energy guzzling ( ergo carbon producing ) commercial air cooler to a recycled, self converted 12 volt unit running from solar panels, preferably home built, makes a difference.
We get to feel good about what we're doing and we produce less carbon.
I am not the only person who believes this.
The number of people who buy sets of solar cells from me (bigpat004) on Ebay (Aus) to build their own panels with is a testament to the truth of it.
If evaporative cooling is not suitable in your area simply get your thinking cap on and use my experience to help you convert a refrigerated unit to 12 volts, or......seeing how quickly my 12 volt car aircon defogs my windscreen (pulls the humidity out of the car) has me thinking that it could be used as an air "dryer" in conjunction with an evaporative unit in the house.....Maybe....
I think us common people have to be the leaders in changing the way our environment is being destroyed.
On our own our voice is merely a whisper easily ignored...together it becomes a roar that can only be quieted with positive action.
All the very best.
Rob Patterson.
A small point on the Air cooler.... We had power blackouts on 3 days over 40 degC last summer. My solar setup and air cooler made ours the only house in town with air conditioning and a working 'Fridge. It felt good :-) .
You could, perhaps, install yours to cool the attic space during normal times but be directed into the existing ducting in case of a power outage.
Cheers Tom.
Rob.
Nothing like a good idea put into action paying off bigtime!
Glad to hear that bit of news!
Tom
Thanks for your question.
The system works very well.
On a day of 100F outside it would be low to mid 70's inside.
Our Summer gets much hotter than 38C (100F).
January and February days are usually between 35 and 45C.
On a 45C day the inside temp would peak at around 27C late in the afternoon.
If I start to feel uncomfortably warm inside I simply go outside for 5 or 10 minutes.
Remarkable how cool it feels inside after that.
The evaporative system works very well if you use it to create a flow of cooled air through your dwelling ie: in one end/side and out the other.
Simply pumping the cooled air into a closed space will not be effective.
Cheers.
Rob.
I have an idea but don't know if it works well (or if really works).
Remove the hot section of your evap. Make a larger, without radiator, with only copper pipe (it needs a long and thin pipe). Take the thin pipe on the roof for the sun to warm it, connecting the pipe coming from the roof to the other side of evap system again. Fill the system with gas normally.
The pipe takes the sunlight and will be warmer. This heat will increase the pressure inside roof pipe and your evaporator will do the rest like using electricity to compress the gas in the pipeline. You just change the place and size of the radiator.
The system remains the same, except that it is not necessary to turn on the compressor, only the fan (there is a refrigerator that runs on kerosene or gas flame - this would be the mode of operation of your system, however, bigger).
Well, you may need to call a professional to do the calculations on the amount of gas, change valves or something more, but it can work. You also need to paint the roof pipe black to absorb more sunlight. I think that more pipe on the roof, more sunlight taken and more heat absorbed in evaporator side.
If it works, will be for a lifetime without power consuption, except the fan electric motor.
You can see something here (in portuguese)
http://www.depijama.com/verdes/uma-geladeira-movida-a-fogo/
and translate here: www.tradukka.com
Watch here:
http://www.youtube.com/watch?v=HSdXqmnNCp0
Search by Adam Grosser - Stanford - fire refrigerator - new gas. It may be your solution.
I thought it pertinent to add some thoughts here.....
I noticed that nearly every Evaporative cooler is sitting out in the open on the roof of it's house in full Sun and figured that didn't make much sense.
The units cop the heat from the Sun and the reflected heat from the roof, which I though must be counter productive.
I checked the temp in my unit while it was shaded and then again when it was in full Sun and the difference inside the unit was +15 deg C higher and there was much more humidity.
To overcome this I insulated the top of my unit with Styrofome panels. This keeps the interior cooler and reduces humidity inside the unit ( ergo, in the house) .
A 90% ( or more ) shadecloth "hat" would work pretty well too.
I also noticed with my unit that when we have a strong breeze blowing it's possible for the unit to work very well without the fan turned on.
The wind does the work.
It'd be nice if someone out there would design a simple set of shutters that would take full advantage of this free wind energy.
That's about it.
Cheers.
Rob.
Thanks for your comment.
You're spot on. No problems with mould or whatever as long as basic hygene principals are applied ie a good hose out at the start of the season and a rinse with household disinfectant as needed.
The wood shavings in the pads are Cypress Pine or similar and have their own disinfectant properties ( another good timber for the shavings would be Western Red Cedar ).
Because we have been using these things for so long here in Aus we understand how they work and use them to create a cool breeze through the room/house rather than just pumping the (cooled and slightly humid) air into a closed room.
Our domestic water is pre-treated with some "ines" and "ides" but I haven't noticed any of the associated chemical smells coming into the house.
If that was an issue then a filter would be in order.
I'm glad you found the "ible" interesting Pedros2.
Cheers.
Rob.
You will see over 90% of houses with swamp coolers.
Most if not all commercial bldgs. use this type of system on a much larger scale to cool the bldg. They would cool down a chill water loop to around 50 degrees and pump it in insalated pipes to evaporator where air would be blowing through them into the bldgs. rooms.
Using a filter could eliminate chlorine and other nasty stuff from entering your house. Insulating the feed water pipes will keep the water cool.
Intercoolers: Basically they are a heater exchanger for air to air or in some applications water to air (when the turbo or blower produces boost it also heats the air, the intercooler allows a chance for that heat to be removed by either air over the fins or water absorbing the heat.) They are also designed to not restrict airflow much unlike trying to force air through a car radiator where the liquid normally would be.
Just a thought. I like the idea though.