Humidifiers

Why do we need to add humidity?

You may have heard that warm air furnaces "bake out the air" and a humidifier is required to add back the moisture that the furnace took out. Well......the furnace really didn't bake the moisture out of the air. (Even if it caused the moisture droplets to vaporize, the vapor is still in the discharge air from the furnace. It wasn't dispelled somewhere else.) The furnace simply heated the air & caused it to expand. The increase in the air volume & temperature is the reason the relative humidity dropped.

Understand that relative humidity is the amount of water vapor, given as a percent, that is actually in a given volume of air, compared to the maximum amount the air could hold at a given temperature. The furnace increased the temperature of the air (and it's ability to hold moisture) and the volume of air. But....it didn't increase the volume of moisture proportionately.

Now we have more air volume, at a higher temperature, but no increase in moisture. What happens? ZOOM.....RELATIVE HUMIDITY PERCENTAGE DROPPED, and the new volume of air became drier. Essentially, we have the same water vapor droplets occupying a larger space, resulting in a lower humidity percentage.