WHOLE HOUSE HUMIDIFICATION

I was hoping for a big step forward – but it ended up being mostly a big step sideways.

Our house gets a little dry during the winter, so every heating season we plunk an evaporative humidifier near the middle of the house and let it do its magic. Of course it is in the way and requires constant refilling. The fan is not too obnoxious on low, and running continuously it can raise our humidity levels to about 35%.

About a month ago, I figured it was time to step things up a notch. So I shopped for a furnace humidifier and found one that supposedly needed little maintenance. I figured that once I finished its easy installation, I could enjoy higher humidity levels using a unit that was out of sight and out of mind.

But it didn’t quite turn out that way. The unit was tricky to install. This particular unit had to be perfectly level in both directions, and the water level set precisely. Otherwise water would either spill over the sides or it would not completely cover the evaporation surfaces. I ended up having to shim the mounting face because even a minor flexing of the furnace ductwork was enough to mess up the water level.

I also learned that I really can’t obtain humidity levels of 40% to 50%. When it is bitter cold outside and the humidity level gets to 40%, water condenses on our windows (which promotes mold). And when the temperature outdoors is more moderate, the furnace does not run long enough for the humidifier to raise the humidity level much. I tried running the humidifier continuously, but very little additional water evaporates when the air isn’t heated. In fact, I am sure the unit would work bettet if the furnace was less efficient (because hotter air absorbs more water).

I am still better off with my new humidifier. It does not need constant refilling and it does not require more than seasonal maintenance. Furthermore, it automatically compensates for changes in outdoor temperature. But I have not been able to realize much higher humidity levels than I had with the cheaper high maintenance unit.