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[dvst8r]

Swamp coolers are very popular in the deserts. They dont cool as fast as ac but are much cheaper to run.

A well setup swamp cooler should actually cool better, as water has a far higher heat load capacity then R-134 or R-404.

But there are a lot of factors that come into play.

[malichite]

I was looking for a cheap way to cool my place down a little too.  I was thinking of huge attic fans one intake at one end and an exhaust at the other.  I noticed my attic is usually really fucking hot.  Anyone ever do something like this and see any results?

[AbaZ]

run hot water through a radiator from a civic with the radiator fan turned on full blast, and attach the hoses to an ouside firew rig.


hydronic heating ftw.


in all seriousness, just get a heater and insulate the damne house jeff. sheesh.

huh?

i was gonna say swamp cooler as well but not sure how well a swamp cooler will actually do in our humidity up here though. it worked great in my house in new mexico but its dry as fuck down there. but yeah, you can pick one up and have it installed for under a grand easy

WHere in Washington do you live that it's humid? Washington is by far NOT humid. Go down south (towards fl) this time of year and you'll know humid

washington is a hell of a lot more humid than vegas, i'm sure vegas and new mexico are similar.
when humidity gets to 10% in vegas people start to complain about the humidity.

Agreed, my dad lives in Vegas. He came up for my wedding (which was the hottest day in WA last year) in Eastern WA. he about fucking died from the humidity.

[d112crzy]

lol, damn. I wonder how he'd feel in 80%+.

[y7turbo]

Uh, residential  HVAC work isn't difficult.

fixed for you.
 



now to the real topic.

it might work when the attic temp is 80 or around there. The blower on the window a/c isnt supposed to be blown through duct, the added static pressure in the duct may overload the little blower motor.. So the supply duct should be left as short as can be..

also, the temp drop across the evap is only ment to be around 20 degrees depending on the humidity and temperature of the space.. So if you have this unit in your attic unless you duct in the return and supply air, you will be pulling in 90+ degree attic air and only supplying 70 or higher degree air into your room.. not only that, if your pulling in 90+ degree return air on the evaporator coil, the suction pressure and superheat will be too high and overload the compressor due to no suction gas cooling the compressor. They are not made to be using high temp return air for long periods of time.


id pass on this one.

[jeffsciv23]

that homemade AC is pretty sweet, i bet it would work alot better if you added ice to the cooler. might have to try that this summer

[Doug]

Humidity here stays around 60-80% year around. Another month and you walk outside and feel the thick ass air hit you like a wall.

[dvst8r]

Uh, residential  HVAC work isn't difficult.

fixed for you.
 



now to the real topic.

it might work when the attic temp is 80 or around there. The blower on the window a/c isnt supposed to be blown through duct, the added static pressure in the duct may overload the little blower motor.. So the supply duct should be left as short as can be..

also, the temp drop across the evap is only ment to be around 20 degrees depending on the humidity and temperature of the space.. So if you have this unit in your attic unless you duct in the return and supply air, you will be pulling in 90+ degree attic air and only supplying 70 or higher degree air into your room.. not only that, if your pulling in 90+ degree return air on the evaporator coil, the suction pressure and superheat will be too high and overload the compressor due to no suction gas cooling the compressor. They are not made to be using high temp return air for long periods of time.


id pass on this one.

First he is putting it in the crawlspace not the attic. [SIDE NOTE ON AC] typically in AC they teach you to put it as high as possible as cool air falls, hot air rises. So he could run ducting to the ceiling and have it drop down, but that sounds like way too much effort.[/SIDE NOTE ON AC] I can't say I have ever been in a crawl space that was 90 degrees, even if it is over 100 degrees out. More then likely it will be more like 70 degrees, so 70 dropping to 50 is reasonable, not ideal but it will work. Especially if he can get it to draw in air from the room as it cools off, and exhaust the hot air out of the crawl space.

The only time temp drop across the evap is "supposed" to be ~20 degrees, is on cheap evap cores (all aluminum or aluminum / copper cores), BUT realistically that is all you need for 90% of the situations. Now keep in mind I stay as far away from residential and commercial AC as I possibly can, you have to work too much and not get paid enough, and there are 10,000 guys out there looking to undercut each other.

[HiProfile]

Tell your wife its a lot easier to smash a plate window than it is to pull an AC unit out of a window. Hell you can spend $7 for a glass cutter, quietly cut a section out, unlock, and you're in to rape & pillage.

If you can turbo your own car, you can secure a window unit sufficiently to deture theft. Otherwise if you have a basement, put it there, then use ducting to move cold into the room & heat from the unit outside.

[y7turbo]

First he is putting it in the crawlspace not the attic. [SIDE NOTE ON AC] typically in AC they teach you to put it as high as possible as cool air falls, hot air rises. So he could run ducting to the ceiling and have it drop down, but that sounds like way too much effort.[/SIDE NOTE ON AC] I can't say I have ever been in a crawl space that was 90 degrees, even if it is over 100 degrees out. More then likely it will be more like 70 degrees, so 70 dropping to 50 is reasonable, not ideal but it will work. Especially if he can get it to draw in air from the room as it cools off, and exhaust the hot air out of the crawl space.

Yeah I didnt see that he was putting it in the crawlspace. Either way, the little  fan wheel and small blower wont be able to handle the added resistance from the duct if its more than a couple feet. The system is not designed for it, If the duct is too small there will be low airflow he will have a unit that will freeze up.

The only time temp drop across the evap is "supposed" to be ~20 degrees, is on cheap evap cores (all aluminum or aluminum / copper cores), BUT realistically that is all you need for 90% of the situations. Now keep in mind I stay as far away from residential and commercial AC as I possibly can, you have to work too much and not get paid enough, and there are 10,000 guys out there looking to undercut each other.

Honestly i dont think you know what your talking about on the evap coils. Copper/aluminum cores have been used forever, and are the choice of all brands unless you need an all copper or coated coil for a space with particles in the air that will eat at the coils or some specialized equipment. I can be workin on a 20ton roof top unit one day and a 300ton unit the next day, they all use aluminum/copper coils.
 Also The temp drop across the evap coils should be around 20 degrees on an air/air evap coil during full load conditions on a normal system. Evap temp drop will change depending on outdoor ambient, indoor drybulb temperature, indoor wet bulb temperature and airflow in CFM through the evap coil.

Now if your talking specialized equipment, its a different story. the system can be designed to do whatever the person wants, but thats going to be different and is the not the same operation as a normal system.

as for the money thing, starting pay here is 20 plus all paid healthcare, dental, pension, and training. The top pay is over 42 an hour on the check plus all the other stuff, Seems pretty good to me. All I do is commercial/industrial work. we work on systems from 3 ton split systems to 500+ ton chillers.

[dvst8r]

We do off-road equipment, specializing in mining equip. and some highway trucks, and some military apps. No reefers as that is a whole other ball of wax.

In stock I carry: a full aluminum (special one off item for one customer only), copper / aluminum (90% of my stock) Copper / copper that has fluted tubes, and a proprietary wave to the fin as well as has a spiral collector with a choke similar to what you see in a good header.

I have pulled open some compact window units that are more expensive and have a higher btu output then avg, and found copper copper cores, and other tricks to give them the greater output in the same packaging. In fact I have used them as cheaper alternatives to custom coils, for prototype units. That is the thing with commercial AC you rarely have a real lack of space for a unit. Either it fits or it doesn't. We spend over a Million dollars each year on R&D most of which goes into trying to decrease the foot print of our mining and military units, while keeping the efficiency where it is.

I am not talking wages, I am talking profit margins. Wages very greatly just by the geographic area that you are in. The profit margins are not in commercial ac like they are in offroad ac.