Humidifiers and Dehumidifiers

Steam & Drum Humidifiers

Flow-through, steam or drum for the whole home

While steam and drum whole-home humidifiers aren't used as often as whole home humidifiers, there are some very specific uses for them.

Steam humidifiers mount under a supply or return air duct. A heating element boils water in a reservoir, and steam blows through the ductwork when needed. Steam humidifiers can come with or without flushing systems to exchange water. They serve very specific needs and aren't for most consumers.

The good:

  • They can be used when the furnace is off.
  • They can provide a lot of humidity. In homes where humidity is in high demand, flow-through systems might not cut it.
  • Homeowners with certain medical conditions may need precise humidification, which steam humidifiers can provide.

The bad:

  • Steam humidifiers can contribute to mold and bacteria growth in the ductwork since water isn't completely evaporated.
  • Purchase and installation costs are high.
  • Operating costs are significant, with heating elements using around 1500 watts or more.
  • Without a flushing system, they require bi-monthly cleaning.

Drum humidifiers , like flow-through, rely on the normal pressure-differential created in a forced-air heating system to direct a portion of the air to the humidifier. The pad is mounted to a drum, which rotates through a reservoir of water. They can come with or without a flushing timer, so they are good for areas without access to a drain and can be a lot easier on water than steam humidifiers.

The good:

  • Because no flushing system is required, they are good for areas lacking drains.
  • Without a flushing system, they must use all water taken in, eliminating waste.
  • Adding a flushing system can make them almost as maintenance-free as a flow-through system.

The bad:

  • Without a flushing system, they need to be cleaned monthly.
  • Using a flushing system means wasting water.

Drum humidifiers can save a lot of water and a lot of money on operating costs, so they're good if that is important to the homeowner. Steam humidifiers cost a lot more but are good for large buildings and places where consistently regulated humidity is needed.