Misting the home AC - PeachParts Mercedes-Benz Forum

Dubyagee · #1 08-05-2007, 05:12 PM

Has anyone ever tried using a misting setup on the outside AC unit to help it dissipate the heat more efficiently. I'm talking about the misting/fogging setups they use at pools and such. I'm thinking about trying it to help with cooling my house a little better. I'm thinking that if it is a ultrafine mist it shouldn't hurt it.

Matt L · #2 08-05-2007, 05:15 PM

We use window units, which do that from the factory. As long as you don't rust out the bottom of the unit, you should be fine. Too bad it's not easy to run the evaporator water out to the condenser, like the window units do.

Dubyagee · #3 08-05-2007, 05:26 PM

I'm thinking of a misting unit that surrounds the AC unit and turns on with the AC or at a specific temp. We use a common well for water (8 homes per well) and I pay a set price per month so my bill wouldn't be affected. I am starting a project to collect rain water for the yard (for higher pressure/GPM then the well) and could tie in this project

Matt L · #4 08-05-2007, 05:30 PM

Wouldn't it be just as good to drip water over the condenser?

Chas H · #5 08-05-2007, 05:30 PM

I think a mister makes great sense, but I have read that mineral deposits can cause problems. The condensate from the evaporator could be pumped out to the the condensor as a source of mineral free water.

Dubyagee · #6 08-05-2007, 05:39 PM

Quote:

Originally Posted by Matt L

Wouldn't it be just as good to drip water over the condenser?

Probably, but I was thinking that the evaporating water vapor would cool the surrounding air prior to the vapor making any contact with the coil. The benefit would be two fold in my mind.

Quote:

Originally Posted by Chas H

I think a mister makes great sense, but I have read that mineral deposits can cause problems. The condensate from the evaporator could be pumped out to the the condenser as a source of mineral free water.

That is a great idea. I am going to see how much comes out on an average day.

Matt L · #7 08-05-2007, 05:44 PM

It doesn't matter where the evaporation takes place, as long as it is before the water leaves the condenser. The evaporating water can absorb a lot of heat from the refrigerant.

Dubyagee · #8 08-05-2007, 05:46 PM

Well, I am going to try it today. I'll post output temp change if any.

Matt L · #9 08-05-2007, 05:59 PM

It's too bad that it's not convenient to measure the head pressure during the test. I would bet on a reduction.

Dubyagee · #10 08-05-2007, 06:31 PM

OK, Its 95 outside @ 100% humidity. It's 78 inside with the thermostat set @ 70.

The air coming out of the vents is 12 degrees colder with the mister on the unit. I am running hose water via a homemade misting tip for this test.

TheDon · #11 08-05-2007, 06:44 PM

dude.. its like 100 here in central FL... I am about to go outside and rig up my hose on that thing

kip Foss · #12 08-05-2007, 09:23 PM

In theory misting is good way to increase the capacity of your ac unit. The problem is that as the well water evaporates the minerals in it will collect on your condenser. Then once a month you will have to acid wash the cond. If you could run distilled water your idea would work.

Your best bet might be to get rid of your condenser all together and use a tube type heat exchanger. Circulate water from your well through the exchanger and back to a near by well. You can also use the ground as a heat sink by burying plastic tubing filled with water/glycol and circulating it through the exchanger. If you are near a lake you can do the same with much better results.

Matt SD300 · #13 08-05-2007, 09:29 PM

Quote:

Originally Posted by Chas H

I think a mister makes great sense, but I have read that mineral deposits can cause problems. The condensate from the evaporator could be pumped out to the the condenser as a source of mineral free water.

Yeah.........Water & electric motors go hand and hand...common sense and all....

Gurkha · #14 08-05-2007, 09:32 PM

Actually water is created as a by product of condensation on Window units, all my Panasonic units create plenty of water to give a splash effect on the cooling coils, they do have a drain unit which is supposed to be kept closed for this effect to commence.

Larry Delor · #15 08-05-2007, 09:34 PM

My cousin was having problems getting her place to cool. I was debating advising them to cool the condenser somehow. Turns out, that their evaporator coil was full of crap - and I mean full! Sticking your head inside the intake you could only see a small amount of what was on those coils. Her husband took off some panels, and cleaned theh hell out of the coils. Now, their A/c actually shuts off during the day. (maybe this will be the end of $300+ electric bills for them vs my $140 - my highest one ever)

So in short....might want to make sure your evaporator is nice and sparkling clean, before spending money.