Either that or grandpa tried to use the microwave again.
10-4. Myās a pretty short typical dryer vent hose they sell. Have thought of making a more elaborate metal pipe so I can vent it inside the house and Iām not throwing away all that nice heat and moisture. Kit actually comes with a small cyclone like device youāre supposed to fill with water to satch the lint that doesnāt get caught by the screen filter.
This is what I want to try also but concerned about my well water being slightly acidic and also maybe leaving deposits, although these are sold with calcium filters.
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If UPS had Good Guys with acetylene tanks, they could put a stop to this.
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Iād never trust it to catch all the lint. There are heat exchangers you can buy to capture some of the heat, but I donāt know how effective they are.
Might be worth a try if your AC unit is getting old and you are willing and able to keep a close watch for any impact on the unit and do maintenance to remove any mineral buildup.
I would be very leery of doing this myself. My greatest concern would be mineral buildup ( a small in-line filter will have only modest effect if your water is hard) and corrosion. Iād also worry about the mist system leaking. Iād use a pressure regulator like those used to limit the water pressure going to yard-irrigation systems.
The theoretical benefits of using water for pre-cooling the air and improving its thermal-transfer properties are so clear that the lack of residential AC units with a factory-built water-misting option tells me that there are too many gremlins in practice for it to work out for manufacturers. They control the design and fabrication, but installation, maintenance, and the operating environment (kids playing soccer around a unit, climbing on top of it, etc.) are out of their hands. There could be room, then, for a homeowner in control of the local variables to make a go of it, but youād be working with a unit that was not designed to work with mist cooling.
If your AC unit only has a few years of life left in it, the cost of trying out the mist cooling might be reasonable even in a worst-case early death of the unit.
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Acetylene gas is more flammable and explosive than hydrogen or natural gas. Acetylene is what is mixed with oxygen to make a blowtorch work.
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Misting works in the short run but fouls and corrodes the condenser coils doom the device to a short life.
Yeah my unit is 21 years old and so in some ways now is the time to try and in other ways I donāt want to push it off the edge any sooner than possible! Probably a better idea might be building a shade to keep the afternoon sun off it.
And then I saw on youtube a guy that had been putting his evaporator drain water down the sides of his outdoor unit and he saw fairly good reduction in KW draw just from that. But I read elsewhere someone tested their evap run off and it was slightly acidic. That seemed odd to me since itās condensing from air so like rain which is typically neutral.
Maybe after I build the shade Iāll look into putting something like a foam around the unit several inches out from it that I drip the condensate through and maybe air passes through it will get cooled before it crosses the condenser coils.
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Search for evaporative cooling pads, because their reason for being is to soak up water and cool the air that passes through. The water evaporates from the pads and leaves the minerals behind (you can get cheap pads that are replaced after mineral buildup or more expensive ones that supposedly allow you to rinse out the minerals).
When I grew up in Southern Arizona, we didnāt have AC. We, and all the houses around us, had an evaporative cooler (also known as a swamp cooler). For those who arenāt familiar with them, and who donāt want to search for info, the coolers were basically a big box on the roof with a large blower inside and a water line to drip water through fibrous pads on all 4 sides of the box. The blower pulled air through the damp pads and blew it into the house. It worked, mostly, as long as the outdoor humidity was low.
Your AC fan might need some help to pull enough air through the pads and then through the coils, but Iām just guessing.
It sounds like you donāt mind tinkering. Most people shouldnāt bother with any modifications and should just make sure they are doing the easy things like replacing filters and blowing dirt/dust off the coils.
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Well Iām a mechanical engineer by trade although not HVAC I like to look into mechanical things to improve efficiencies. My wife and I laid out our house to be passive solar and I had hot water solar panels for 20 years that I only recently took of due to needing a new roof. Also the system was in the attic and a pipe solder joint let loose due to freezing during a really cold snap this winter and caused some flood issue. The controler seemed like it was dying and Iād already replaced it once before. So Iām thinking that if I put on some more panels Iāll try photovoltaic instead to reduce water issues!
Yeah a swamp cooler for the outdoor unit is what Iām thinking might be fun to try. Hereās one a guy made for his outdoor unit. Interesting that his died at 21 as thatās how old mine will be this Augustā¦gulp
https://www.builditsolar.com/Projects/Cooling/ACEvapCool/ACEvapCool.htm
This is interesting and low budget, wrapping the condenser with a soaker hose!
Low budget swamp cooler. This is kind of what I was thinking a few inches away from the condenser coils. My wile will love the blue!
This kind of looks like a combined unit of misting onto a pad in front of the colis
http://www.mistecology.com/
And this company tries to give you the best of both worlds by alternating wet and dry sides.
http://www.climatewizard.com/wp-content/uploads/tech/cw-technical-explanation.pdf
This seems like it might work but I have a hard time it works this well and the fact the video is 10 years old and Iāve never seen one make me wonder too.
But along these line it might be interesting to try and pull air through a dry side through the cond. coils and out the top. And pull air and water up through a wet sides using vacuum created by putting the outlet in the stream of the fan. Hummm.
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https://www.lowes.com/pd/Dial-Foamed-Polyester-Evaporative-Cooler-Replacement-Pad/3092793
I have a BSME, but would consider it deceptive to describe myself as a mechanical engineer (Iām no Ryan Zinke).
My parents in Tucson have had a breadbox solar DHW system for decades. I donāt know what work theyāve had to do on it over the years, but they remain happy with it. Water up on the roof is obviously a potential problem where the climate is cold enough to require something more complex than an insulated box to prevent freezing.
- He says deep south and over 90F ā how is he not sweating? Just the thought makes me sweat.
- Thatās a lot of water
- His 150F temperature measurement is in full sun, there is a cloud blocking the sun later on ā not sure how much difference that would make, but more than zero.
- Give the guy credit for banging away at a problem with what he has at hand
Since I am not an ME, my brain started to object when I considered trying to follow the M-cycle in the Coolorado unit. However, I did find a nice DoD analysis of the Coolorado technology performance and economics. The two pdfs linked at the bottom of the page are perfect recreational reading for an ME. It appears that the energy savings is very real, though climate sensitive (as you would guess with evaporation involved), but the initial cost is pretty high. Other articles indicated that Coolorado is not currently pursuing residential markets, and that the company was purchased by an Australian firm ( https://www.seeleyinternational.com/us/ ).
Good luck with your tinkering! Let me know if you make any interesting discoveries.
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Meant to add ā eventually, you will settle on a geothermal heat pump, so just dig the trenches now and get it started. 
I thought about geothermal, but supposedly a lot of the current AC units these days are such high efficiency the extra initial and maintenance cost of a GSHP are not worth it. My parents had one that had a seperate well from their drinking well and just used that water to pull heat and cooling from rather than outside air but then just dumped the water on the ground. I didnāt think their power bills showed much savings that I remember. Seem like a loop would require less pump energy and plus not waste water. Dad would water his lawn and garden in the summer with it.
Googling a bit it seems like my shade idea isnāt really worth it.
But if I added the swamp cooler to the shade, it seems like it might make a difference.
I need to get a clamp on amp meter before I try all this to see what is anything these changes make.
Got to find the break in my hidden dog fence first!
The dog is way ahead of you.
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So are a lot of other folks and animals!
And on the AC, one interesting comment I read was that someoneās window unit actually did have a way to splash some of the condensated water on the condenser coils.
Our window unit has cost us about $1.50 in electricity in the 22 months since we bought it. It spent 10 months in the box, and the next 12 months in a San Diego window close enough to the ocean that we have been able to get by without using the AC function and just occasionally using the fan setting.
There is a high initial cost for the San Diego window, but you canāt beat the operating cost after that.
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Itās also whatās formed and burned in an old minerās carbide lamp (or some of the original automobile headlights)!