A few buying tips will make your humidifier shopping easier. If you are not sure that you really need a humidifier, you may want to measure the humidity level in your home with a hygrometer. They are inexpensive and can help you monitor the air you breathe so you can take action to maintain it at the optimum level.
Review the recommended moisture level in controlling moisture. Sorting through humidifier details can be daunting and consumers have lots of questions. Check out some Humidifier Fast Facts for the answers.
Determine the Type of Humidifier You Need - Cool vs Warm Mist
First, you need to decide what type of humidifier you are looking for - warm or cool mist, or whether a dual unit would be more convenient. If you're not sure, learn the difference between a warm and cool mist humidifier to help you determine what is best for you.
Read why some feel a cool mist is safer when young children are present. There are also models that humidify and purify (or wash) the air - these are usually a more expensive, but may be worth considering.
For more about maintaining a proper home humidity, read about Controlling Home Moisture and learn why too little or too much humidity can be problematic.
Type of Humidification Processes
There are basically two types of processes that a humidifier might use to generate moisture or steam - evaporative which is more common and generally the cheapest, and ultrasonic which produces a finer water mist.
Either type can be used for warm or cool mist models, but ultrasonic is considered safer since it does not produce a mist by boiling water. Therefore the humidifier does not contain hot water that could create a hazard if the unit was knocked over.
Humidifier Styles: Personal, Portable, Console or Flow-Through Bypass
A personal humidifier is a very compact, no more than 1-liter that can be taken on trips to provide moisture where you need it. Though efficient for personal use, the coverage area is limited. Also considered portable, a room humidifier can vary in capacity from compact to large room size and is most commonly used in bedrooms or living areas.
A console model is a large, free-standing unit on wheels. Because of the larger capacity and efficiency, console models are considered whole-house units. Another type of whole-house humidifier is a flow-through bypass unit that must be installed on the home's duct system.
Sizing the humidifier to the room size is most important. Humidifiers are rated for a coverage area in square footage. Take measurements to determine the correct room size you are looking for. Models for 700 square feet are adequate for a bedroom or small room.
If the humidifier is too large for the room, condensation will appear on the inside of the windows, and bacteria and mildew could grow in this environment. Capacity is usually denoted on the packaging, but it should not be confused with moisture output which will be more than the water tank capacity. Water tank size is often a convenience decision.
Controlling Moisture Output
While some humidifiers are basic in moisture control with two or three variable fan speeds, others may have a built-in hygrometer to indicate the moisture level in the room and a humidistat that you can set for the unit to cycle on/off to maintain the proper level. Unless you want to monitor the room's moisture level and adjust settings to maintain it, these measurement features are very handy and worth the extra cost.
Portable room units are sold in varying sizes of water reservoirs, from 1 liter to 5 gallons or larger. This is a convenience factor - how often do you want to refill it? A 2-gallon will usually run for 12 or more hours on low, but a 1 liter will require refilling every 8 hours or so.
Runtime will decrease substantially if the unit is operated on high and how dry the air is will also affect how fast moisture is added to the room. Packaging or product description will usually denote how long the unit will run on a filling.
Ease of Handling & Maintenance
Some water tanks are a little harder to remove and refill, some lift off easily. Could the weight of a full tank be a problem for you? Take time to inspect the unit to see how easy the water tank removes from the base. Also note if the model will require filter changes, check on availability, as well as how easy they are to change. Consider purchasing a couple of filters along with your new humidifier as maintenance is crucial to reduce the risk of bacteria and unhealthy air.
Operation Noise Level & Settings
Expect some operating noise from a humidifier, but if the unit is for a bedroom, you may want to look for one with a low, night or silent setting. This being said, my silent model is not really that quiet, but we adapted quickly to it. It actually helps to 'drown' out other household noises.
You should have at least two settings on the unit, high and low options. Ultrasonic humidifiers are considered the quietest to operate since there is no boiling of water (hissing) and moisture is expelled in a very fine mist.
Benefits of Changing Humidifier Filters
Most room humidifiers have filters. Evaporative models have wick filters that trap dust and particles. Some units have two-stage filtration which is important for removing allergens. Mineral deposits in the water form a white dust that accumulates on the furniture in the room, but some filters will trap these deposits and reduce the presence of dust in the moisture that is expelled to the room. Those with hard water may benefit from using distilled water in their humidifiers, reducing the build-up of scale and mineral deposits.
Safety Shut Off & Other Features
Digital controls offer more convenience. Many models have safety features where the unit will shut off automatically when the water reservoir is empty - a must-have feature. If you cannot tell from the packaging, this is certainly worth asking the retailer. Otherwise, you need to be diligent to shut it off when it runs dry. Another great feature is a built-in humidistat which regulates the operation to maintain the set humidity level in your home.
Regular Maintenance & Warranty
All humidifiers require regular cleaning to reduce bacterial growth. Check the product information as some models have dishwasher-safe water reservoirs, which make cleaning easier. The base of the unit also requires a manual cleaning regularly. Warranties are generally 1 year, but there are some models with longer periods. These units are affordable and replacement usually is more economical than trying to get it serviced after the warranty expires.
More About Buying Air Quality Appliances
Even if your humidifier has a built-in hygrometer, monitoring your home's moisture level all year with a separate hygrometer, is important. It's not unusual for a home to require a humidifier to add moisture during winter months when the heating system is operated, but during spring and fall, a dehumidifier is needed to remove excess moisture from certain areas of the home.