We have long known that running forced-air furnaces in the winter lowers the humidity in the house. They promote health and they keep old furniture from cracking and falling apart.
In the past we have had pad/drum-type humidifiers attached to the furnace, and, quite frankly, they are a royal pain. The minerals in the water are deposited on the pad and the mechanism, requiring hours of cleaning now and then.
The last house we lived in we decided instead to use a cool-mist humidifier. We put it in the upstairs hallway, and the quiet noise (!) didn't bother us much. When we moved to our current home in a high-rise condo, we gave that humidifier away.
But now, two years later, we have realized the the air in our unit is pretty dry in the winter, and so, once again, we have been looking for a way to humidify the air.
We expected we would not want a warm mist humidifier because those humidifiers heat the water and leave deposits on the heating element. We've had them, and they work, but they don't seem very efficient.
So we were considering a cool mist humidifier and the newer, ultrasonic humidifiers.
The cool mist humidifiers have the drawback of being noisy, and the ultrasonic humidifiers apparently leave a fine dust all over the place. A difficult choice.
Our first attempt was a Honeywell cool-mist humidifier, advertised as being 30% quieter than othe cool-mist humidifiers. Ugh. We put it in the hallway, and it drove us crazy with the noise. One tankful of water, and it went back to the store.
Our second attempt was a Bionaire ultrasonic humidifier. We had anticipated the problem of its possibly leaving dust everywhere, so we filled it with filtered water (we have a Culligan filter on our kitchen tap, and it works very well). No problem with the dust, but the humidifier is too small to help much in our entire unit.
So I went to buy another one, but for some reason decided to buy a Honeywell instead. They have a larger-capacity ultrasonic humidifier, but it doesn't have a warning light to let you know when it is out of water, and we had already noticed that we liked that light on the Bionaire; it clearly isn't necessary, but it is handy.
Instead I bought a smaller Honeywell, with the red light that turns on when the unit is out of water. Unfortunately the window showing the water level is made of very dark plastic, so dark we could not see the water level!
So back it went to the store, and I just bought a second Bionaire. So far they seem to be working well, and it seems that our decision to use filtered water has licked the dust problem. Quite possibly using filtered water would also make the warm mist humidifiers more attractive as an option, too.
In the end, though, refilling these suckers once or twice a day, just to keep the humidity up between 35% and 40%, is probably going to become a royal pain. I expect that at some point we will have to look into seeing if we can get a small water line run to the furnace so we can install a drip-pad type humidifier.