heater31 wrote:Swampys begin to lose their effectiveness at about 38 degrees from memory.....at 45 degrees totally useless!
Yes, and no.
Hot dry outside air is drawn in by a fan through a wet cooling pad, this process takes the heat out of the air before being pumped into the building.
In dry climates, like ours, this also adds moisture to the air giving more comfort to the building occupants. ( Relative humidity of about 45% is good for most people ).
The cooling potential for evaporative coolers is dependent upon the difference between dry-bulb and wet-bulb temperatures. ( Dry-bulb is dry thermometer shielded from radiation and humidity and wet-bulb is a thermometer covered in a wet towel with air passing over it ).
Your cooler at home should reduce the outside air temperature to within 3-4°c of the wet-bulb temperature. If the difference between dry-bulb and wet-bulb is too high then the coolers ability to take the heat out of the dry air is reduced.
In essence the air being drawn in from outside is still being cooled and saturated but not enough to get the temperature closer to wet-bulb than dry-bulb, thus you "feel" like it isn't working, it is but not as well.
PAFC. Forever.
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