Prove me wrong, please?
edit: thanks for all the great comments, this is really helpful. My main take-away is that it does work, but requires dry air. In humid conditions it doesn’t really do anything.
Spouse bought this thing that claims to cool the air by blowing across some moist pads. It’s about as large as a toaster, and it has a small water tank on the side. The water drips onto the bottom of the device, where it is soaked up by a sort of filter. A fan blows air through the filter.
- Spouse insists that the AIR gets cooled by evaporation.
- I say the FILTER gets cooled by evaporation.
- Spouse says the cooled filter then cools the air, so it works.
- I say the evaporation pulls heat (and water) from the filter, so the output is actually air that is both warmer and wetter than the input air. That’s not A/C, that’s a sauna. (Let’s ignore the microscopic amount of heat generated by the cheap Chinese fan.)
By my reckoning, the only way to cool a ROOM is to transport the heat outside. This does not do that.
We can cool OURSELVES by letting a regular fan blow on us = WE are the moist filter, and the evaporation of our sweat cools us. One could argue that the slightly more humid air from this device has a better heat transfer capacity than drier air, but still, it is easier to sweat away heat in dry air than in humid air.
Am I crazy? I welcome your judgment!
OP, where do you live? What is the surrent relative humidity of your house? The lower it is the more likely this thing is to work. It is a legitimate technology but they only work well in dryer places. A dry heat is perfect for this.
These are often called swamp coolers.
You sound persnickety. You’ll probably like this persnickety video about swamp coolers
These work so long as the air around them is not humid already
Swamp cooler, they do work, but raise the humidity, which might cause increased mold growth
It’s been crazy hot and humid this past month where I live. This thing would kill me
Technology Connections has a video on exactly these devices that dives into how they work and what they can and can’t do. TLDW; you’re not wrong about the physics of cooling a room, though in some cases this little thing might make you feel a bit cooler.
I was about to share this! Always glad to see Alec get recognition!
I’ve had one before. They are def not a good enough replacement for AC when you really need it, but they’re not useless, either. They certainly don’t work like AC does, you are right. They can make you feel a little cooler if you’re sitting in front of it. lol
Pro tip: Dowse the pad insert in water and put it in the freezer. You can also put an ice cube or two in the water reserve. Both of these things maximize the “cooling” power, but again, you can’t really expect it to cool a whole room.
Thank you for this. I admit that I smiled at your tip to freeze the soaked filter, because freezing it requires the fridge/freezer combo to do so, and where does that unit vent its heat? Into our living space, of course.
So it’s a closed loop with losses, and I found that funny.
