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As the owner of a whole house fan + evaporative cooler, and someone who lives in a city where hundreds of thousands of people own and operate them, I invite Mr.

As the owner of a whole house fan + evaporative cooler, and someone who lives in a city where hundreds of thousands of people own and operate them, I invite Mr. Kaufman to visit Albuquerque, to watch them in everyday operation, where we've been swamping it up for over 50 years. It's a bit bizarre to read about it as if it's a brand new theory. Let me clear up a few misconceptions: You put the fan on the inlet next to the "pad" where the water soaks in (nowadays usually located at a central point on the roof). This works a lot better than a single outlet point for a number of reasons, not least of which the source of air can be made to have reduced dust. (Imagine a leaf blower or old diesel next to a window on a structure with negative pressure). There are never circumstances where a whole-house fan is made less effective with humidification. It may be no more effective, but for those 100% humid nights where it's cool enough to cool down the house, the swamp still runs. In humid environments, it may warm up the house at night (due to temperatures, not humidity), which is why swamps don't get used in most places.

athorax 8y ago
I'm originally from the 505, and now have an evap cooler + whole house fan in Denver. I agree that swamp coolers are very popular in Albuquerque, but I can't recall ever seeing a whole house fan down there. Are they fairly common?
- mchannon 8y ago
  If you define a whole house fan as a whole-house swamp cooler without any evaporative media or water line, then, no. If you define a whole house fan as the part of the whole-house swamp cooler that is a huge fan and covers the whole house, whether there's water going to it or not, then, well, yes. We'll occasionally run the thing dry when the water part is on the fritz or half-shut down for the winter.
  - djrogers 8y ago
    > If you define a whole house fan as the part of the whole-house swamp cooler No - that's not what this is. A whole-house fan is a high volume extraction fan, that removes warm air from your house and expels it, usually into your attic (thus displacing hot air which also helps). Cool air is drawn in to the house through open windows, so you can control what rooms get breezes or get cooled first. While it's interesting to know that people use swamp coolers where you live, you appear to have completely missed the point of the article.
    - jcrawfordor 8y ago
      Swamp coolers always work by displacing the indoor air with outdoor air, if they recirculated indoor air they would drive the humidity up until they were ineffective (one pass through my cooler already puts the indoor RH at 50-60%, vs. about 10% outdoors). The difference is that, in addition to replacing indoor air with outdoor air, a swamp cooler can also use evaporation to cool the outdoor air so that this is effective even when it's warmer outdoors than indoors. This does mean that you have to have windows open for a swamp cooler to function... visit a house in Albuquerque and the combination of swamp coolers and crime mean that you'll see window iron or wooden props everywhere so that air can go out without burglars coming in! The blowers in swamp coolers are powerful too, often producing a constant indoor breeze. Mine slams doors if I'm not mindful. A normal practice for cooling is to run the blower when outdoor temps are lower than indoor, and then both the blower and pump when outdoor temps are higher. Thermostats are available but not very common on swamp coolers, one reason is that independent control of the pump and blower makes them a bit more complicated than an "on/off" behavior, and another is that they take time to displace the indoor air so they work best if you anticipate the daily trends by cooling the house farther than target before temps really climb in the late morning. During weather like we have in Albuquerque right now, lows in the '70s and highs in the '90s, you will run the blower 24/7 but might stop the pump when the house gets cool enough. I've thought about it a bit and I can't really see how what's described in the article is different from the normal "best practice" for swamp coolers - bringing in outside air, with or without additional evaporative cooling depending on the outside temperature. He refers to the advantages of closing up the house to retain the cool air, but if that's sufficient (and it is for a while in spring and fall) you just turn off the swamp cooler and close the windows during the day, no extra hardware is needed.
      - cbr 8y ago
        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.
schiffern 8y ago
> There are never circumstances where a whole-house fan is made less effective with humidification. It may be no more effective, but for those 100% humid nights where it's cool enough to cool down the house, the swamp still runs. This. Put simply, the wet bulb temperature is always colder than the dry bulb temperature. https://en.wikipedia.org/wiki/Wet-bulb_temperature https://en.wikipedia.org/wiki/Wet-bulb_temperature
- deleted 8y ago
  [deleted]

athorax 8y ago

I'm originally from the 505, and now have an evap cooler + whole house fan in Denver. I agree that swamp coolers are very popular in Albuquerque, but I can't recall ever seeing a whole house fan down there. Are they fairly common?

mchannon 8y ago
If you define a whole house fan as a whole-house swamp cooler without any evaporative media or water line, then, no. If you define a whole house fan as the part of the whole-house swamp cooler that is a huge fan and covers the whole house, whether there's water going to it or not, then, well, yes. We'll occasionally run the thing dry when the water part is on the fritz or half-shut down for the winter.
- djrogers 8y ago
  > If you define a whole house fan as the part of the whole-house swamp cooler No - that's not what this is. A whole-house fan is a high volume extraction fan, that removes warm air from your house and expels it, usually into your attic (thus displacing hot air which also helps). Cool air is drawn in to the house through open windows, so you can control what rooms get breezes or get cooled first. While it's interesting to know that people use swamp coolers where you live, you appear to have completely missed the point of the article.
  - jcrawfordor 8y ago
    Swamp coolers always work by displacing the indoor air with outdoor air, if they recirculated indoor air they would drive the humidity up until they were ineffective (one pass through my cooler already puts the indoor RH at 50-60%, vs. about 10% outdoors). The difference is that, in addition to replacing indoor air with outdoor air, a swamp cooler can also use evaporation to cool the outdoor air so that this is effective even when it's warmer outdoors than indoors. This does mean that you have to have windows open for a swamp cooler to function... visit a house in Albuquerque and the combination of swamp coolers and crime mean that you'll see window iron or wooden props everywhere so that air can go out without burglars coming in! The blowers in swamp coolers are powerful too, often producing a constant indoor breeze. Mine slams doors if I'm not mindful. A normal practice for cooling is to run the blower when outdoor temps are lower than indoor, and then both the blower and pump when outdoor temps are higher. Thermostats are available but not very common on swamp coolers, one reason is that independent control of the pump and blower makes them a bit more complicated than an "on/off" behavior, and another is that they take time to displace the indoor air so they work best if you anticipate the daily trends by cooling the house farther than target before temps really climb in the late morning. During weather like we have in Albuquerque right now, lows in the '70s and highs in the '90s, you will run the blower 24/7 but might stop the pump when the house gets cool enough. I've thought about it a bit and I can't really see how what's described in the article is different from the normal "best practice" for swamp coolers - bringing in outside air, with or without additional evaporative cooling depending on the outside temperature. He refers to the advantages of closing up the house to retain the cool air, but if that's sufficient (and it is for a while in spring and fall) you just turn off the swamp cooler and close the windows during the day, no extra hardware is needed.
    - cbr 8y ago
      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.

schiffern 8y ago

> There are never circumstances where a whole-house fan is made less effective with humidification. It may be no more effective, but for those 100% humid nights where it's cool enough to cool down the house, the swamp still runs. This. Put simply, the wet bulb temperature is always colder than the dry bulb temperature. https://en.wikipedia.org/wiki/Wet-bulb_temperature https://en.wikipedia.org/wiki/Wet-bulb_temperature

deleted 8y ago
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