1. Home

Humidifier Fast Facts - What You Should Know About Humidifiers

Understanding Humidifiers & What to Expect When Using One


If you're finding humidifier information confusing, you're not alone. From capacity to warm or cool mist functions, I'll clear the air and give you straight basic humidifier facts that you need to know. It will help you to make good humidifier buying decisions and also give you a better understanding of the care you'll need to give this air quality appliance. If you're not sure what a humidifier is or what it does, review my humidifier definition to learn why this is an important household appliance.

1. Do You Need a Humidifier?

Mature man hydrates with home humidifier.
Patti McConville/The Image Bank/Getty Images

Your physician may recommend that you to buy a humidifier to help you breathe better, remedy dry skin or help a certain medical problem.  In this case, you should also inquire as to what type - warm or cool mist, he or she would recommend.

But consumers often make a humidifier buying decision simply based on how they feel or what they see happening in their home. A home that is too dry can cause some health problems, but it can also damage furniture and musical stringed instruments (wooden). 

A hygrometer is the best measure of humidity levels, but you can also learn the signs that your home may need more moisture.  Then find a humidifier that meets your preferences when it comes to convenience, maintenance and price.

Signs You May Need a Humidifier

What's a Hygrometer?

2. Quiet Operation - Myth or Fact?

You'll find many humidifiers sporting a 'quiet' or 'whisper quiet' product description.  One humidifier may be quieter than another by design, such as an ultrasonic model which is known to be quieter than some other types, but there are no totally silent humidifiers.  Having at least two speed levels allows you to pick the lowest (quietest), or a nighttime setting.  As you would adapt to an air conditioner or fan's operating noise in order to benefit from the improved comfort level in a bedroom, you have to do the same with a humidifier - get used to the noise level.  It can have its good points - a low operating hum can drown out irritating household noises and it can remind you to fill the unit or turn it off.

Also see: Ultrasonic vs Evaporative Humidifiers

3. How to Decide on Humidifier Size

Buy a humidifier sized for the area where you need to add moisture, not on a humidifier's capacity. Every humidifier is designed for a certain coverage area in square footage. Use that as a guide, measure your own area and match the humidifier to this area. Don't oversize the unit - you'll likely end up with excess moisture problems. It's better to err on the smaller size. When buying a whole house humidifier, keep in mind that though they are designed to cover a large area - your whole home, how well moisture is discharged to the full area depends on your home's layout.

4. Where's the Best Place for a Portable Humidifier?

While placing a humidifier in a family room because it's the largest area or where everyone can benefit from it may seem wise, you should place the humidifier where you need it the most, as long as you've sized it for that room. Most common places for portable units are bedrooms. However, it really depends on what your needs are and if you want to simply add moisture to a dry room, or benefit personally from extra humidity.

5. Capacity Does Not Relate to the Water Tank Size

Humidifiers are sold by capacity but this does not refer to the water tank size.  It relates to the amount of moisture output over a 24-hour period.  To achieve the stated output, the humidifier may have to be filled more than once (the water tank will be smaller) and the unit may also need to be operated on high. 

6. How Often Does a Humidifier Need to be Filled?

You'll most likely need to fill any humidifier every day. A one-liter unit running for 8 hours on low will need to be filled daily, as would a 3-gallon humidifier which may operate for 12-15 hours. Even a larger 10-gallon console model should be filled regularly, simply because it's easier doing it daily, rather than when it is empty. With a portable unit, you should empty the tank completely, then refill - not simply add more water to it. That's because bacteria breeds in stagnant water and you can reduce that risk by emptying the water tank completely, washing and drying if possible, and then refilling with water. This is not so easy with a console model, but it should be done at least on a regular basis for the same reason.

7. Evaporative or Ultrasonic Humidifier - Which is Better?

Evaporative is the most common (and basic) type of humidifying process and it's usually the cheapest. An ultrasonic model produces moisture differently, often in a very fine or invisible mist and usually costs more. Some find ultrasonic humidifiers quieter to operate. Learn more about what an ultrasonic humidifier is and how it works.

Ultrasonic vs Evaporative Humidifiers

8. Built-in Moisture Control - A Help But Not Enough

A built-in humidistat is certainly a nice feature but don't trust it fully. How it works:  You set the preferred moisture level and it controls operation to maintain that humidity level. However, some find that these features generally have some flaws - some do not reach the designated level. While they help to a point, for your own peace of mind to avoid over-humidifying your home and creating an improper moisture balance, buy an inexpensive hygrometer and monitor your humidity levels, then adjust the humidistat to ensure that the humidifier is working as it should.  Learn the difference between a hygrometer and humidistat.

9. Maintenance is a Must - for all Humidifiers

If you don't want to take the time to maintain a humidifier, you're better off not having one. That's because you'll negate any moisture relieving benefits by spreading bacteria around the room, from a humidifier that is not cleaned on a regular basis. Some recommend cleaning the humidifier with vinegar and disinfecting with bleach monthly, but most find they have to do this every week. How often depends on various factors including mineral content in your water, room air quality, how long water has been standing and how fast particles build up in the filter. And warm water breeds bacterial growth more quickly than cool. Even though you do not need to change a permanent filter, you'll need to clean it and disinfect the unit just the same.

10. Germ or Bacterial Control Features

Some humidifiers have built-in bacterial control features to prevent or reduce the risk of bacteria forming in the water tank or at the point of moisture output. These and other features such as nano or silver eon technology are excellent for helping to keep bacterial growth down. You'll pay more for these features but they are worth having. But keep in mind that these do not eliminate cleaning the humidifier. You still need to be diligent and do a good routine cleaning and disinfecting of your humidifier. There are some humidifiers that use silver sticks for bacterial protection and these have to be purchased and replaced occasionally.

Promotional Feature: View this video series to learn how to take good care of your house.

Related Video
How To Buy A Humidifier

©2014 About.com. All rights reserved.