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  • Annoying shocks from static electricity
  • Itchy, dry skin
  • Always feeling “too cold” despite normal thermostat settings
  • Irritated sinuses and sore throats
  • Static cling problems with clothing and linens

A whole house humidifier automatically humidifies air in the home to keep you comfortable

A lack of humidity during the winter months can cause many of the problems listed above. For our fall/winter project we will discuss and demonstrate installing a whole house humidifier. We will also provide links to the products used in our project.

It is not uncommon for homeowners to purchase small, portable humidifiers to provide a more comfortable environment in a living room or bedroom. These portable units work well for a small spaces, but require frequent refilling, cleaning and maintenance.

If you have a forced air heating system in your home, you are probably a candidate for a whole-house humidifier. You can leverage your forced air system to distribute humidified air through your entire home. Unlike portable systems, a whole house humidifier requires no bottle or reservoir filling, and can provide the right level of humidity to every room in your home. This whole-home solution is silent, automatic, and is installed out-of-sight and away from living spaces. These units have no standing water and no buckets to clean or empty. Maintenance is limited to changing out water panels (sometimes called filters) on an annual or bi-annual basis.

Is installing a whole house humidifier really a do-it-yourself project? Well, that depends . . . The installation of a humidifier is a multi-disciplinary project that requires a level of comfort with electrical wiring, plumbing, and sheet metal working. If you are not comfortable with any of these items – consult a HVAC professional to do the job. If you are comfortable with these items IAQSOURCE.COM provides the necessary components to get the job done (see project kits below).

Whole house humidifiers are generally categorized as bypass or powered models (see illustration at right). Either type will require the following steps:

  • cut a hole in supply or return side of furnace plenum for unit mounting
  • wire and provide power and/or continuity through unit humidistat control
  • plumb water supply to solenoid valve on unit
  • provide for drainage of excess water into drain or pump

Bypass humidifiers will require the addition of a bypass duct running from one side of the unit to the opposite side of the forced air furnace.

Powered units have their own internal fan, and don’t require this extra ductwork. The type of unit you choose will depend on space available on ductwork for installation, size of space (in square feet) to be humidified, and cost. Generally, bypass models are less expensive than powered units – while powered models are more expensive but are easier to install.

End-Of-The Season Closeout Pricing
Aprilaire Model 700 Humidifier
Provides up to 4,200 square feet of humidification. Includes automatic humidistat that tracks outdoor temperature and adjusts humidity level to prevent condensation on windows.
MFG#: 700
Aprilaire #35 Water Panel Evaporator, 2-Pack
(case of 2 Water Panels)
MFG#: 35
Powered Humidifier Installation kit
Honeywell HE265DG115 (HE265D) Enviracaire Elite By-pass Humidifier
Provides up to 4,000 square feet of humidification. Small footprint, lightweight and reversible components allow for easy mounting on either warm air supply or cold air return of most forced air furnaces.
MFG#: HE265DG115
Honeywell HC26E 1004 Humidifier Pad, 2-Pack
(case of 2 Water Panels)
MFG#: HC26E1004
Bypass Humidifier Installation kit