Cool-N-Save to lower airconditioning cost

No, I have not seen it, but obviously a simple good idea.

This comes from the Cool-N-Save website:

Installed in less than five minutes with no tools required, the Cool-n-Save™ system affixes to the top of most home air conditioning units. The system is activated only when the AC unit turns on; hot air from the condenser unit’s fan raises the flap on the patented Cool-n-Save™ control valve allowing water to flow to the misters that surround the AC unit. When the ultra-fine mist is released into the air, it evaporates almost instantly creating what is known as a “Flash Evaporation,” which literally sucks heat out of the air as water absorbs the energy it needs to evaporate. The result of the immediate evaporation constitutes a substantial drop in ambient temperature without wetness—up to 30 degrees Fahrenheit.

I'm definitely no expert on heating and cooling systems...but I've read that, in winter for example, if your thermostat is set to 68 degrees F with a relative humidity of 35%, it will feel as warm as a room set at 72 degrees with relative humidity of 19%.

But...it seems like the Cool-N-Save principle goes against the notion that moister air feels warmer.

There is no conflict between Cool-N-Save and the notion you mentioned.

You feel warmer in the moister air, because you lose less heat from your body. When there is more water in the air around you, evaporation of perspiration (which takes heat away) is less.

Cool-N-Save uses the same theory; the mist sprayed on to cooling fin takes heat away from cooling unit. So, the heat dispertion efficiency is improved.

When the humidity is 100%, howeveer, COOL-N-SAVE won't work, because there will be no evaporation of mist in 100% humidity air.

High humidity blocks evaporation of perspiration, which is human's natural body temperature controlling system. 77 degreeF with 95% humidiry (like summer day in Tokyo) is 100 times more uncomfortable than 104 degreeF with 15% humidity (like in Phoenix, AZ).

It's a good idea

I have asked many distributors about this concept and never got an answer. The only thing I have found on the net is by a company selling it as in the next paragraph.

According to Microcool at www.microcool.com this only comes into effect at +37 deg C (100 deg F). You can check their site for confirnmation

Hi Brian, There are 'misters' which operate at low pressure (2.5 to 5.5 barg - 40 to 80 psig) and 'dry fog' systems which operate at approximately 69 barg - 1000 psig. 

The 'dry fog' high pressure systems such as Microcool (and any other same type system) seem to serve your purpose but what Microcool seems to point out is that under 37 degrees C (100F) they will have no benificial effect. Then it also depends on the relative humidity.

Low pressure sprays would leave the air saturated plus free water in the air stream. Any free water could leave solids on the condensor coil.

'dry fog' (high pressure spray) would not have that problem.  

I have used dry fog for dust suppression on an industrial basis and was very impressed by it. It could control cement dust with no wet/dry interface problems simply because there was not wet to be concerned with. 

Now studying the U of Tulane document - much is well over my head!

Looking forward to you receiving the unit and your results.

Good luck,

Russ 

I bought one ast summer and the air comming out of my vents in the house actually feels cooler than it did prior to installing it. After a month or so of use my entire electric bill went down measurably - about 12 %.

Yes, as a matter of fact there is a bit of white residue on the screens sround the unit - we have SUPER hard water here in Houston. I plan to spritz it with some vinegar and use a brush to remove it & maybe kill the surrounding weeds while I'm at it, too, I hope.

Vinegar shouldn't hurt aluminum - both are used in cooking  but think of cleaning scale out of the coffee pot - unless you heat it not much of the scale comes out. Brushes on the fins (probably you can't get to most of the fins) could easily do damage - the scale adheres to the metal quite well. Frequent cleaning may be one solution.

I don't have much hope for the filter - it is not a suspended solid in the water you are trying to get rid of but a disolved solid. Filters are not sold as water softners which they would be if it worked.

This spray seems to be a 'wet' spray as compared to the dry fog type. The dry fog would not leave any contamination on the fins. The dry for operates at high pressures of 55 to 70 barg (800 to 1000 psig). The Microcool site refers to it working above 37 deg C (100 deg F) - maybe the free water in the spray is the reason the Cool-N-Save works. 

Private user is Brian Kanto, having issues with my account, really only leaving this message so I can return message to stins, which I can't do until I have 3 posts, all but 2 are now gone

Well, I have the cool-n-save after a month as I said. I also said it looked cheap, even cheaper than the picture. I hooked it up as instructed exactly. it was not hard, worked for an hour, clogged in the valve somewhere. These are micro-holes, I can't clean it out. So, it is junk, but I don't believe the concept is. i will contact them tomorrow, see if I get an appropriate response. I know they ran low, the valve does not resemble the one in the pic, so maybe the old one worked better. As I read it, sometimes pieces of the filter can break loose and clog it, as stated on their own website Someone not watching the bottom line so intensely could design a better one. How about you Russ? Will keep you posted.

Hi Brian, Sorry to hear about the quality!

I am trying to figure out the function of the 'micro holes' metering or water flow restriction?

What type of spray nozzle do they use. Information on the cool-n-save site is rather lacking. 

I like the part about the filter when they talk about 'industrial heavyweights' designing the filter then mention no name but their own.

Hi again Brian, Is this the 'flapper' valve you are talking about?

Hi Russ,

It is the flapper valve. The input hose enters the flapper valve into a small chamber, with the smallest of holes, like 16G wire that is open by the valve going up. All I can imagine, is that as their website states, a piece of the filter broke loose and clogged it. I call that a design issue. Anyway, I bypassed the valve with a Tconnector to to mister arms and turned it on manually in the afternoon for a couple of hours yesterday (it was 94). They use standard mister heads found on the shelf for backyard misters

The inventor called me and left a message. He said to much solution from the filter may have clogged the valve. So he told me to take some needle nose pliers and give the pin under the flap a tug or two, which I did. It now works as it was designed to. Now I just have to fix my spigot, that leaks a little. Will keep updated on  both if the air has is colder and if it runs for shorter periods of time.

Glad to hear it is back on line - at 94 degrees it has to be nice to have all the help you can get!

May be more trouble than it is worth but what I would prefer is to have a solenoid valve in the line which is energized when the compressor loads up. A needle valve would possibly be required to throttle the water flow.

 I found one already on the market Russ.
https://nerissa.secure.kgix.net/~ezmister/index.php?option=com_phpshop&page=shop.browse&category_id=11&Itemid=26

Spent 30 minutes on the phone with the inventor of Cool-n-save, if I understand him correctly, the company that does the filter is http://www.dobergroup.com/water-treatment.php. He guarantees no calcium buildup, but states you might have some white mineral build up that can be removed with a 50% vinegar spray. He is sending me a whole new unit, because of the trouble. I plan to ask him to post something here.

Hi Brian,

To add to what you supplied from a site I ran across about water treatment:

Polyphosphate:
Generally, polyphosphate feeders are effective in low volume, cold water applications. The polyphosphate dissolves into the water and coats the iron, calcium and magnesium in it, making it impossible for these agents to precipitate out of the water and create the problems associated with hard water.

Polyphosphate crystals are placed within a housing and as water flows through it, the crystals dissolve.

Polyphosphate is also available in a more traditional filter. These filters are effective for relatively small quantities of water, and are commonly used in low volume applications such as refrigerator ice makers, etc.

Unfortunately, polyphosphate-type systems are only effective in cold water, low volume applications. It should also be noted that phosphates are a preferred "food" for bacteria - so if bacterial contamination is a concern (in private, non-chlorinated water supplies, for example) you may want to reconsider using a polyphosphate system.

It answers a few of my questions about the filter and why I haven't heard of it. Everything I learned in industry is for large volumes and even for the homes we are building we are talking about whole house systems.

The one site you mentioned - 

ezmister does a lot better explaining and making clear the limits - I appreciate a site that is open about limitations and expectations. 

Thanks Russ, I believe he said his filter was better than those and that he would go into anytime I wanted. He gave me his personal cell phone, called me back at 9 pm last night.