Author here: I don't know very much about how swamp coolers are used in practice, so I could easily be missing something. I do know that they're basically never used up here in the Northeast (Boston) because they work by increasing humidity and in the summer we tend to have pretty high humidity already. We also tend to have daytime highs high enough that the air leaving a swamp cooler would be warmer than the temperature of a structure that's been cooled overnight with a whole-house fan, plus more humid, which means during the hotter parts of the day you don't want to bring in outside air. So, how could a swamp cooler be used without increasing the daytime humidity of the house?What I'm imagining is running a swamp cooler overnight to cool the structure of the house as close to the wet bulb temperature as possible, then in the early morning run it a bit in fan-only mode to bring in drier outside air (accepting that this will warm the house up a bit), and then shut the house up and turn the cooler off for the day.
What we currently do is run a whole-house fan overnight, and shut the house up during the day, with no swamp cooler. I'm trying to figure out whether adding some evaporation to the system could make sense.
mchannon|7 years ago
Evaporative cooling is not worth doing in Boston for the space in a residence. It can be used, however, to improve the efficiency of refrigerated air units. Take a look at air conditioner misters that spray hose water onto the radiators for refrigerated air units. Although I suspect a good percentage of that heat is carried away simply by conduction rather than evaporation, it could conceivably cut your air conditioner bills. Water-cooled whole-house air conditioners are high maintenance, otherwise they'd be commonplace.
The other approaches involve tag-teaming a refrigerated air unit with a swamp cooler. The air intake for a refrigerated air system would work a lot better at 80 degrees, 80% humidity than 90 degrees, 60% humidity. I am told this is commonplace in Phoenix.
One other often-overlooked characteristic of the "swamp cooler zone" is that it tends to be at high altitudes, which aside from keeping things dry and cool enough to have a shot at good-enough cooling, requires doubling the size of refrigerated air units to keep pace with design specs. The air is thinner enough up here that the radiator can't keep up as well. This shifts the balance slightly in the direction of swamp. This has been what feels like an unusually hot and humid summer in Albuquerque, and our household finally sprung for a room air conditioner, run in parallel with the swamp.
cgdcraig|7 years ago