What Does a Humidifier Do?

What Does a Humidifier Do?

Cracked lips. Itchy eyes. Nose bleeds. If you regularly experience these, then one possible cause is dry air. Our bodies need water, not only to drink but also to moisturize us.


Drying yourself out too much can cause discomfort and make you more susceptible to getting sick.



What Does A Humidifier Do?

A humidifier adds water into your home’s air when there isn’t enough there naturally. Dry climates like the southwest simply lack moisture. In northern climates, homes get dried out during winter due to forced-air heating.


Humidifiers are controlled by a humidistat, which measures the amount of water vapor in the air. The recommended humidity level for homes is between 40%-60%. Anything below 40% humidity is considered dry and could damage floors, furniture, and your health. Studies have shown that viruses and bacteria can travel more easily in dry air and cause infection.*



How Does a Humidifier Help?


Humidifiers have the potential to help with everything from dry skin to snoring by adding moisture to the air. Check out some of the possible health benefits of humidifiers below.


What does a humidifier help with



How Do Humidifiers Work?

All humidifiers add water to the air, but there are various humidifier types that accomplish this differently.


Evaporative humidifiers work by moving air across a wet wick, drum, pad, or other media. As the air passes over the media, it causes the water to evaporate, which adds moisture to the air.


Steam humidifiers boil water into steam that is then injected into the air. They are much more efficient than evaporative models but use more power and are scalding hot.


Impeller humidifiers use rotating discs that splash water at a diffuser that breaks it into droplets and releases it into the air.


Ultrasonic humidifiers use a metal plate that vibrates ultrasonically. The ultrasonic vibrations break water into tiny vapor droplets that are then infused into the air.


Warm Mist vs Cool Mist Humidifiers

Each humidifier type also produces either a warm or cool vapor. Typically, evaporative, impeller and ultrasonic humidifiers are considered cool mist because they don’t heat the water. Steam humidifiers boil water, so they are always considered warm mist.


Cool mist humidifiers are safer for children because they don’t boil the water, and they also use less power. The downside is that bacteria and other contaminants can thrive in this cooler water and be released into your home. As a result, they need to be cleaned often.


Warm mist humidifiers are more expensive to run and can cause burns if used inappropriately, but the boiling water kills most germs. The warm mist is also believed to be more soothing for breathing passages, especially if you’re sick.


Portable vs Whole-house Humidifiers

Honeywell TrueEASE 17 Gal. Basic Bypass Evaporative HumidifierIn the broadest sense, humidifiers can also be broken down into portable or whole-house types. As their name implies, portable humidifiers can be moved around the home and must be manually refilled with fresh water regularly. Some are small enough to rest on a nightstand while others need to be wheeled. Even the largest portable humidifiers can only moisturize one room at a time, however.


Whole-house humidifiers are installed directly into your home’s ductwork and add humidity to your entire house. They can either bypass furnace air into a separate duct, where it picks up moisture from a pad before flowing throughout your home or directly infuse hot steam into the air stream.


Water is automatically fed to whole-house humidifiers through a dedicated line, so you never have to manually refill the basin. Typically, either evaporative or steam-type humidifiers are used in whole-house applications.


TIP: Evaporative whole-house humidifiers need your furnace running in order to work. Steam whole-house humidifiers will work if your blower is running, even if your furnace isn’t. During the summer, you close the damper leading to the humidifier so that you’re not adding moisture to an already humid home!


Humidifier Sizing


If you are going the portable humidifier route, you will need to have at least one unit in every room you spend significant time in, such as your bedroom, living room, and kitchen. At a minimum, you should have a small one near your bed at night to help you breathe better while sleeping, especially if you have a cold or flu.


If you have chronic dryness problems in your home or need extra humidity for health reasons, then a whole-house humidifier is recommended. Sizing a whole-house humidifier requires two basic pieces of information:


  1. How Much Space is in Your House? Calculate building volume in cubic feet by multiplying your home’s square footage by the ceiling height.

    For example, a 2,000 square foot home with 8-foot ceilings would have 16,000 cubic feet (2,000*8=16,000)

  1. How Drafty is Your House? The faster your house loses air through cracks and gaps, the more humidity you’ll have to pump into it. In other words, how well insulated is your home?

    Not sure how to judge how drafty your house is? Another name for this is building envelope, and the table below can help you decide whether you have a tight building envelope (very little air gets in or out) or a loose building envelope (very drafty). Using the table, decide if your building envelope is loose, tight, or somewhere in between (average).


Building Envelope Chart


When you figure out your cubic feet and building envelope, it’s time to determine what size humidifier you need, measured in gallons per day. Find the intersection cell of your home’s building volume and building envelope in the table below for an estimate of how many gallons per minute your humidifier should be.


Sizing a humidifier


  • For steam humidifiers, select the humidifier that has a capacity greater or equal to the load listed.
  • For evaporative humidifiers with a furnace, double the load listed.
  • For an evaporative humidifier with a heat pump, triple the load listed.

Installing a Humidifier

Portable humidifiers don’t require any special installation. Just take them out of the box and read the owner’s manual. Whole-house humidifier types are far more complicated and require a professional installer, especially if bypassing ductwork.


How to Clean a Humidifier


Over time, mineral deposits from water and other contaminants will accumulate on your humidifier’s parts, and you don't want them getting in the air you breathe. 


To clean portable humidifiers, follow these steps:


  1. Unplug the humidifier.
  2. Disassemble the humidifier, separating the tank from the basin.
  3. Pour water into the tank, adding one tablespoon of white vinegar for every 32 ounces of water.
  4. Let the water/vinegar mixture soak for 15-30 minutes.
  5. Repeat Step 3 for the humidifier basin
  6. If you still see mineral deposits after soaking, scrub them off by hand using a paper towel and vinegar.
  7. Rinse all humidifier parts with cold water to get rid of the vinegar smell and any remaining grime.
  8. Dry the parts with a paper towel and reassemble the unit.


The above instructions will vary depending on your specific unit, so consult your owner’s manual for exact cleaning procedures. Try and clean your portable humidifier on a weekly or biweekly basis. If you use filtered or distilled water in your humidifier, you’ll need to clean less often because there will be fewer deposits.


Cleaning whole-house humidifiers: Evaporative whole-house humidifiers contain a removable water panel that should be taken out and cleaned at least twice per year according to the owner’s manual instructions. Experts also recommend replacing the panel on an annual basis for optimal performance. Similarly, steam whole-house humidifiers have a water canister that should be replaced annually.



Humidify Your Home


As you can see, there are many different options for adding humidity to your home. Choosing the right humidifier comes down to your unique situation. Do you only need extra humidity in your child's room for when they catch a cold? Consider a cool-mist portable humidifier. Is your entire house always dry? A whole-house humidifier is for you.


If you're not sure what's best for you, please give us a call and explain your needs. Our knowledgeable representatives will steer you in the right direction. Just contact us for more information.


NEXT: Shop All Humidifiers


*For informational purposes. Not Medical Advice.


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