Does a ceiling fan lower a room's temperature?

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rich000 said:
No. Put a thermometer in the room without the fan running and check the temperature. Turn on the fan and then check the temperature.

Tell us what you find out.

CFs cool by windchill. Inanimate objects do not feel windchill. You need water to experience wind chill.

Now, if you use a wet bulb thermometer, you might get a different temperature.

However, the home's air conditioner uses a thermostat that is probably not a wet bulb.

So, if you leave the room, turn off the fan.
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The correct way to test the air is with a device called a sling psychrometer. It has two thermometers one is dry the other you wet a cotton ball that is wrapped around the bulb. The thermometer is attached to a string and handle you then twrill this contraption around for about a minute then read the two temps. If the ambient temp. is say 90 the wet one will be around 4-6 deg. cooler. As many have stated its the evaporating effect on your skin that makes it seem cooler. They use the same principle in chicken houses they have misters spraying a fine mist of water with large fans pulling air through the building feels good on a 100 deg. day:grin:
 
zog said:
. . . BAF claims the wind chill effect lowers the temp 4-16 degrees, depending on speed.

When we crank this baby up to 7 . . . it sure cools the shop :)
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You do understand that this is perception only, right? It only feels cooler. Same as with the heat index, which takes huidity into account.
 
ceb58 said:
They use the same principle in chicken houses they have misters spraying a fine mist of water with large fans pulling air through the building feels good on a 100 deg. day:grin:
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A giant swamp cooler, aka an evaporative cooler.
 
ceb58 said:
The correct way to test the air is with a device called a sling psychrometer. It has two thermometers one is dry the other you wet a cotton ball that is wrapped around the bulb. The thermometer is attached to a string and handle you then twrill this contraption around for about a minute then read the two temps. If the ambient temp. is say 90 the wet one will be around 4-6 deg. cooler. As many have stated its the evaporating effect on your skin that makes it seem cooler. They use the same principle in chicken houses they have misters spraying a fine mist of water with large fans pulling air through the building feels good on a 100 deg. day:grin:
Click to expand...

I've never seen a sling thermometer. I used to use a wet bulb thermometer in industrial spaces (could you sling yours around in a small space?). The wet bulb also had the cotton ball with an internal fan to pull the air across the wet cotton. I think I remember it being called a psychrometer. It definitely was not a sling though.
 
ceb58 said:
They use the same principle in chicken houses they have misters spraying a fine mist of water with large fans pulling air through the building feels good on a 100 deg. day:grin:
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This process actually cools the air.
It requires about 970 btu's of heat to evaporate 1 pound of water.

As the water is sprayed into the air stream, it evaporates, and absorbs heat.
As long as the air doesn't reach saturation, the cooling effect will continue.
This requires "make-up" air, because if all the doors and windows are closed, the air would soon become saturated with water and the cooling (evaporation) would stop.

steve
 
hillbilly said:
This process actually cools the air.
It requires about 970 btu's of heat to evaporate 1 pound of water.

As the water is sprayed into the air stream, it evaporates, and absorbs heat.
As long as the air doesn't reach saturation, the cooling effect will continue.
This requires "make-up" air, because if all the doors and windows are closed, the air would soon become saturated with water and the cooling (evaporation) would stop.

steve
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I didn't know the the BTU numbers hillbilly quoted but I see the football teams using "swamp coolers/misting fans" on the sidelines. I've also run a fan outside and injected a mist into the air with a garden hose. Man does it work!:grin: :grin:
 
LarryFine said:
You do understand that this is perception only, right? It only feels cooler. Same as with the heat index, which takes huidity into account.
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Huidity??

Yeah, I know it is perception only, but that hurricane force breeze feels good on a hot summer NC day.
 
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