So what’s the takeaway? Use a humidifier but make sure it works correctly and is properly maintained (which of course is why you are here!)
A central humidifier is a special piece of HVAC equipment fixed to the furnace that adds water vapor to air discharged by your furnace. There are also stand-alone humidifiers for use in a single room. Humidifiers are used primarily in the winter heating season when humidity levels are low, as evidenced by frequent static electricity discharge, dry skin or nose bleeds. Newer tightly constructed homes have much less air infiltration than older homes. As a result, humidity levels are more easily maintained, reducing the need for a humidifier.
- There are three main types of central humidifiers you may find in the home. However, this tutorial will address maintenance of the reservoir and flow-through types, the two most common types of humidifiers and the two which also require the most maintenance for proper operation:
- Reservoir humidifiers use a rotating drum styled foam pad or similar media that picks up water from a float controlled reservoir for evaporation.
Drum Style Humidifier - Flow-through drip style humidifiers use a specially coated metal or plastic screen that has a small amount of water constantly dripping across it while the furnace is running.
Flow-Through Humidifier - Steam humidifiers contain self generating steam heaters and are the most expensive, lowest maintenance and most efficient. These humidifiers however require water to have a certain range of hardness and quality. Some homes may require filtration options to alleviate problems with water quality and hardness.
Honeywell Steam Humidifier
Let’s review maintenance tips on the next pages for the reservoir / drum style humidifier and the flow-through / drip style humidifiers.


