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What is The Difference Between Cool Mist & Warm Mist Humidifiers?


Question: What is The Difference Between Cool Mist & Warm Mist Humidifiers?

What is the difference in cool and warm mist humidifiers and how do I know if I need one?

Answer: There are only a few differences between warm and cool mist humidifiers and the type that is better for you may depend on which type is recommended by your physician, or which unit helps you breathe better.

From my own experience I've found that the cool mist usually makes breathing easier for asthma and allergies. If you find it hard to breathe in a sauna, a cool mist would probably be better for you. On the other hand, if a sauna makes it easier for you to breathe, a warm mist is the better choice.

Warm Mist Humidifiers

These humidifiers actually boil the water which causes a distilled steam to be expelled into the room. This steam is like a gentle spray of warm water, as opposed to a vapor, and this is concentrated in the area closest to the humidifier. This warm mist is easier to breathe in a cool room. These units are often also used for steaming medications and are usually designed with a small med compartment.
Warm Mist Humidifier - Definition

They are a little quieter than cool mist humidifiers and are sold in small portable units. They do require more frequent cleaning due to the fact that warm water, which encourages bacterial growth, is in the unit. Also, you should be aware that some find warm mist humidifiers to have more risk of injury because of the hot water and heating element. See section below on safer humidifiers.

Cool Mist Humidifiers

Cool mist models are slightly noisier, though some models have a 'silent' feature for operating in bedrooms. There are basically two types of cool mist humidifiers - evaporative and ultrasonic They pass the water over a wick and expel a vapor, that cools down the room temperature and makes it easier to breathe. They vary in size and design, from units that are connected to the home's heating duct work to be circulated through the whole home as the heating system operates, or come in larger portable floor console units, or smaller room size models.
Cool Mist Humidifier - Definition

All humidifiers require regular cleaning to reduce the risk of bacteria, and some models have filters which require changing to maintain performance levels.

How Can I Tell If I Need One?

If you suffer from chapped lips, dry skin, sinus problems or a dry cough, you would probably benefit from the use of a humidifier. A house that is too dry will cause static electricity to form as well as cause wooden furniture and the wood in musical instruments to crack and mar their finish.

How Do I Know How Much Humidity Is Right?

You can often tell that your home is too dry simply by the presence of chapped lips or itchy, dry skin. But the best way to know is with a hygrometer, which measures the humidity levels in your home. A healthy humidity level is between 35 and 50 percent - a higher humidity can cause moisture problems. Musical instruments require around 40 percent humidity to be maintained in the room, to reduce the risk of crazing or cracking of the finish.

Over 50 percent humidity can cause bacteria, dust mites and mold spores to grow. If you don't have a hygrometer, a sign that there is too much humidity in your home, would be the evidence of mold, or condensation and steam dripping on the inside of your windows. Read more about maintaining a proper moisture control in your home.

Is One Type of Humidifier Safer than the Other?

Since a warm mist humidifier has hot water present in the tank as well as a hot heating element, this type of humidifier has an added safety risk. For this reason and for peace of mind, some consider a cool mist humidifier safer to use when small children are in the home. However, when additional care is taken to reduce this risk, either type of humidifier can be used safely. Learn what steps you should take for safe humidifier operation:
Which Humidifier is Safer - Cool or Warm Mist?
General Appliance Safety Tips

Read More About Humidifiers & Air Quality:

Whole House vs Portable Humidifiers
Humidifier Buying Tips
CADR - What This Rating Tells You About a Humidifier
Why Changing Filters is a Good Idea
Go to Main Humidifier/Dehumidifier Page
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