Hi, Asher,
Oh, sorry. That's slang for
evaporative coolers, a system for cooling houses and other buildings that is workable in areas of low relative humidity.
We see what certainly are two of them in your image "
Wall of Comic Book Heroes ", on the roof.
They work by having a blower draw in outside air through porous pads soaked with water. (They typically are behind grilles on three, sometimes four sides of the unit housing. The classical construction is a mat of aspen wood shavings.) The water evaporates gladly (if the humidity of the arriving air is low enough) and in doing so cools the air. The cooled (and substantially humidified) air is then set via ducts to the area to be cooled.
The water is drawn from a little pan (filled from the domestic water supply through a float valve) by a small pump and discharged at the top of teh pads through perforated tubes.
These are much less costly to operate than "refrigerative" air conditioning systems of the same cooling capacity. They are not usually automatically controlled, but are rather operated by a set of (usually) three switches on the wall. One turns the blower on and off, one sets the blower speed to one of two values, and the third operates the water pump.
These were at one time almost universal in New Mexico, and in fact, a number of the houses on our block still have them. (Our house had such in its early life.)
The most common deployment is on the roof, as it facilitates the routing of the ducts. But some are on a pad at ground level. My house in Albuquerque (1968-1971) had a swamp cooler at ground level. The ducts ran in the almost-basement (which of course is not a common thing to have in New Mexico)
Decades ago, they were also common in Dallas, but the increasing ambient humidity over the years eventually made them almost useless.
In come cases, these were "add-ons", mounted adjacent to a window and discharging through same.
Best regards,
Doug
