Saturday, May 30, 2009


Something for readers unfamiliar with the desert Southwest.

The last few days have turned cool and cloudy and we've been getting some unusual (for the time of year) rain. Nonetheless, it has warmed up enough for me to engage in that uniquely Southwestern ritual- filling and servicing the swamp cooler. "Swamp coolers" or, more accurately, "evaporative coolers" are the most common way of cooling houses out here.

One friend jokes that you should get your cooler set up by the Fourth of July and drain it by Halloween, but more realistically we typically have a hot spell in early June and you don't want the cooler, or more accurately the tubing bringing water to the cooler, to freeze while full of water which is a definite risk by mid to late October.

These are really simple devices, basically a box with a pan of water, a pump to run that water through some screens of damp material, and a blower to pump air through the damp screens and into your house. With our low humidity, a swamp cooler will cool most houses pretty well. In addition, at night when it drops down into the 60s or 70s you can just run the fan to move air through your house. Maintenance is easy and operating costs fairly low.

Here it is:

Here's the inside:

A squirrel-cage fan:

Run by an electric motor:

A water pump:

That pumps water from the tray it rests in up through the blue tube and then through the black tubes at the top of previous photo. From the black tubes on top the water runs into these channels and flows through the pads and screens:

I prefer natural pads, which are made from aspen wood which is shaved into fine strips:

The smell of the fresh pads as they get wet always brings to mind coolness and gives a hint of the aspen groves they came from. Besides, they're biodegradable and easily renewable. You have to replace them every year, but they're inexpensive, which cannot really be said for the plastic alternatives.

So, hook up the water, sweep any old scale (left by our hard water evaporating) and dirt out of the cooler, replace the pads, fill the cooler, check for leaks, make sure the pump and fan are running ok (and grease the bearings on the squirrel cage) and you're ready for the heat.


Matt said...

While the traditional dates for swamp-coolering are July 4 and Thanksgiving, they are flexible. In the springtime, the actual date must be a day so unbearably hot that you burn your fingers on tools and your knees on the roofing tar. A 40 mph wind is also de-rigueur. A typical hook-up also involves at least 5 trips to the hardware store and ten trips up and down the ladder. In most homes, the heater or the cooler can be hooked up at any one time, but not both. Therefore, in the fall, gusty arctic canyon winds and snowfall can accelerate the process, to be done in the dark, after work, so the pipes don't freeze. The flimsy water supply line has already been unhooke, but not drained, during the last blizzard, in a usually fruitless effort to keep it from bursting (whether or not this was successful (not) will not be determined until next July 4.

mdmnm said...


I'm pretty familiar with the phenomenon of the unhooked, but not drained, water supply line and the attendant leaks.