Should You Buy a Warm Mist or Cool Mist Humidifier?

March 23, 2016 • By

Difference-Between-Warm-Cool-Mist-HumidifierShould You Buy a Warm Mist or Cool Mist Humidifier?

When the winter months hit, we are all often left feeling chilly and turning up the temperature. Yes, this helps to keep us warm, but it also completely dries up the air in our homes – leaving us with dry skin, chapped lips, a sore throat or congested sinuses. To relieve this problem, just run a humidifier in your home to add much needed moisture back into the air.

When purchasing a humidifier, you’ll be presented with two different types of this appliance — warm mist and cool mist. The easiest way to choose which one is best for you is to decide on what type of air is easiest for you to breathe in.

Even though both are humidifiers, both types have their own way of operating, own set of benefits and who they are best for. To make a more informed choice when purchasing your humidifier, here is a breakdown of both cold and warm humidifiers; how they work and the pros and cons each of them have:

Warm Mist Humidifier

The best way to know whether a warm mist humidifier is for you is to be thinking about how you breathe in a sauna or steam room. If you feel claustrophobic and struggle to breathe, you should avoid this type of humidifier. But if you inhale well in these steamy conditions, then a warm mist is the best option for you.

How It Works?

As the name suggests, this appliance releases warm mists. The warm mist humidifier does this by heating up the water inside of it and releasing a warm mist or hot steam into the air. The water is heated up by an internal heating element that boils the water – turning it into steam. The humidifier then releases an invisible warm mist into the air.


  • If you live in a cold climate, using a warm mist humidifier will help make the room feel warmer than it actually is.
  • Because of a warm mist humidifier boils that water that is released into the air, it is considered healthier than a cold mist humidifier. The boiling process kills waterborne bacteria and mold and prevents them from being released into the air. Therefore, you’ll only be breathing in a pure, clean mineral free moisture output.
  • Another benefit of this type of humidifier is that it doesn’t have an internal fan – making it extremely quiet compared to cool mist humidifiers.
  • Unlike the cool mist humidifier, this humidifier has no wick filter so there is no need to replace it.
  • Some warm mist humidifiers even have a medicine cup in the appliance that disperses a soothing vapor through the room. This is especially helpful for newborn babies with asthma or congestion symptoms.


  • Adding warm, moist air into a room can encourage the growth of mold which is why people that suffer from allergies would be better off using a cool mist humidifier.
  • Warm mist humidifiers are a little more difficult to clean too since mineral deposits are often left behind during the boiling process.
  • Because there is a heating element in the humidifier, it has a higher power consumption than other humidifiers.
  • The heating element and warm water that it produces may also cause a risk with small children or pets who accidentally tip it over or get to close to the dispersing area.
  • Unfortunately, a warm mist humidifier can only be used for small rooms; otherwise, it becomes ineffective.

Best For

Warm mist humidifiers are not as well-suited for large areas. They are best used in smaller areas like bedrooms and offices. However, many people have found these humidifiers to be more comfortable for use during cold winter months.


Safety is a huge issue when it comes to using a warm mist humidifier as it uses heating elements to raise the temperature of the water in the tank. The water in the tank reaches boiling point and poses a potential danger to children and pets. Warm mist humidifiers aren’t advised for homes with children as they present very real and potential burn risks.

Cold Mist Humidifier

Allergy or asthma sufferers will have an easier time breathing with a cool mist humidifier. By extracting any impurities from the air, these humidifiers will allow you breathe in the cleanest air possible.

How It Works?

Untreated dry air enters the system around the side and back of the humidifier. The dry air passes through the saturated wick filter that sits in the base of the humidifier and absorbs water. A fan then blows dry room air through the saturated wick filter causing the water in the filter to evaporate into the room. This, in turn, adds moisture into the air.  The wick filter also traps any impurities that may be in the water – ensuring that the moisturized air is completely pure, clean and free of any minerals or impurities.


  • Because the water is not heated before it is dispersed, these humidifiers typically use less electricity and are more cost efficient.
  • Cool mist humidifiers are also the better option if you have young children and pets in your home as they do not use boiling water.
  • The wick filter also ensures a pure and clean mineral-free moisture output.
  • Cool mist humidifiers are the best option for adding moisture to large areas or even entire houses as the fans can be powerful enough to cover large areas with a single humidifier.
  • It also brings down the overall temperature of the room – making you feel cooler during the warm summer months.


  • Cool mist humidifiers tend to make more noise than warm mist units. Since these devices use fans to blanket your room with moisture, they can be slightly noisier than warm mist humidifiers.
  • Even though during the summer months a cool mist humidifier can be refreshing as it lowers the temperature of a room, in the winter months it can cause the air to be slightly chillier.
  • The wick filter inside the cool mist humidifier needs to constantly be replaced as bacteria and mold can grow on it. Most wick filters should be replaced approximately every 2 months although some models have cleanable, reusable filters.

Best For:

Many parents opt for cool mist humidifiers to avoid hot water accidents in children’s nurseries, bedrooms or other living spaces. If you have children or mischievous pets, this type of humidifier might be the best option as the vapor won’t burn the skin when touched. Cool mist humidifiers are also ideal to add moisture into larger spaces as the fans help the air to move.

Things to Remember When Running a Humidifier:

Keep Your Humidifier Clean

No matter which model of humidifier you are using, it is extremely important to keep your humidifier clean.

In cool mist humidifiers, this means replacing the wick filter and ensuring you clean the water tanks with vinegar. Warm mist humidifiers have a higher chance of mineral deposits left behind in the humidifier, but these can also be simply removed by using vinegar. Make sure to also read your user manual and follow its specific maintenance and cleaning instructions, especially if your humidifier is still under warranty.

Use a Hygrometer

When running a humidifier, you’ll also want to use a hygrometer. This simple device measures how much humidity is in the air. Make sure that your humidity level does not go above 50 percent since that will encourage the growth of mold spores, bacteria and dust mites. A humidity of 35 to 45 percent is optimal.