Central Humidifiers: Is a Standard Model Good Enough?

January 17, 2017

The Colorado Front Range is considered a semi-arid region, and many of us appreciate the relatively low humidity that our climate provides, especially during the summer. But when winter rolls around, our Colorado air can feel downright uncomfortable after it gets heated up inside your home.

As air is warmed, it requires additional moisture to maintain the same comfort level. Central humidifiers are the best solution to supply additional moisture to homes that have forced air heat. There are several styles of central humidifiers, and this discussion will focus on the flow-through type of design, which is the most commonly installed due to its simple design and relatively low cost.

Advantages of Proper Indoor Humidity

There are many advantages to having an appropriately humidified home. Helping to relieve common respiratory and skin ailments; reducing airborne viruses and bacteria; helping protect wood furniture, wood flooring and musical instruments against cracking; reducing airborne dust; and, providing equivalent comfort at lower thermostat settings (= lower utility bills!) are prominent benefits of maintaining humidity within a desirable and consistent range.

Central Humidifier Options

There are two families of humidifiers most commonly available for homes with forced air heat. The first group is comprised of high performance models that boil water to create humidity, and are referred to as ‘steam’ humidifiers. A steam humidifier is the best option for those wanting to establish and maintain a specific and consistent humidity level, 24 hours a day. The second family of humidifiers, which we’ll referred to as ‘standard’ humidifiers, uses simple evaporation to create humidity. Standard humidifiers are more suited to families that can accept wider fluctuations in performance.

The most popular type of standard humidifiers have a flow-through type of design. Let’s take a closer look at flow-through humidifiers and discuss how they operate, their anticipated performance, and the pros and cons of owning this type of product.

How Does A Flow-Through Humidifier Work?

A furnace-mounted, flow-through central humidifier incorporates a special media water panel, oriented so that water flows down through the panel while warm air from the furnace is directed across it. Most of the water is evaporated and delivered to your home through the ducting system. The water that isn’t evaporated after passing through the pad is discarded into your home’s drain system. The humidifier can optionally be wired to operate whenever the furnace fan is blowing (with or without the heat operating), to provide continuous humidification. However, it will produce only marginal results when the heat is not running, while sending significant amounts of water down the drain. For water conservation purposes, having your standard humidifier set up to operate only in the heating mode, rather than fan mode, is typically recommended.

To conserve water, there is one model of flow-through humidifier that captures the wastewater so that it can be wicked back up into the media panel, rather than discarding it to a drain. While this ‘wicking design’ saves water, it also carries maintenance and performance complications that may result in regrets for the owner. When choosing a flow-through humidifier, a basic flow-through design is your best bet.

The amount of moisture generated by your central humidifier is regulated by a humidistat control, much like a thermostat, except that this control ‘talks’ to the humidifier instead of to your furnace. More elementary systems have the humidistat located at or near the furnace, while more elegant solutions allow you to control the humidity from your thermostat. Your HVAC professional can provide you with choices to fit your needs.

Performance Expectations

As we’ve learned, a flow-through humidifier requires that the furnace is operating in the heating mode to work at its peak performance. Flow-through humidifiers can generate a significant amount of moisture each day, typically in the 12 to 18 gallons-per-day range, but that assumes that the heat is running consistently. When you apply the fraction that your furnace actually runs on any given day, the production will often be significantly less. That’s one of the ‘disadvantages’ of our often pleasant, sunny wintertime weather in Colorado–the furnace just doesn’t run often enough, much of the time! Thus, during extreme cold periods, with the heat running steadily, flow-through humidifier performance is pretty darn good–while on more moderate days, or when the sun is warming your house, it can be difficult to meet your humidification goals.

Other factors that impact humidification performance are the size of your home (volume) and how well it is sealed. Small to moderate sized homes that are well sealed will have more success with a standard humidifier than large or leaky structures.

Advantages Of Flow-Through Humidifiers

Compared to other design units, flow-through humidifiers offer a number of advantages:

  • Most affordable style to have installed.
  • Low maintenance requirements.
  • No standing water to foster bacterial growth.

Routine maintenance is relatively simple and can often be performed by the homeowner; or, this work can be done by your HVAC professional for a relatively low cost along with your regular annual maintenance.

Limitations Of Flow-Through Humidifiers

Compared to high performance steam humidifiers, standard humidifiers have some limitations:

  • Humidity percentage attained is inconsistent and can be inadequate, at times.
  • Consumes more water since some of the water passes through to a drain.
  • Typically won’t satisfy the needs of large or leaky homes.

In summary, a conventional humidifier can do a satisfactory job when the weather cooperates and your furnace runs constantly. And, if you don’t have high expectations, these basic, reliable units will at least be putting out more moisture than you’d get without a humidifier. For those with more specific indoor humidity requirements, learning more about a central steam humidifier would be in order. More on those next month.

Denver & Boulder, Colo. Homeowners, Call Us Today!

For homeowners in the Boulder and Denver, Colorado area, contact Save Home Heat Company today to learn more about humidification for your home, and to get expert advice and recommendations for a central humidifier to help improve indoor comfort levels and health during the heating season. Count on Save Home Heat to help you improve the indoor environment for you and your family this year!