While you'll enjoy the benefits of adding humidity to a dry home, you can easily tip the scale and then have to deal with excess moisture. As mentioned above, a hygrometer will help you to monitor humidity levels. Signs that you are adding too much moisture to your home include water or moisture accumulating or dripping on the inside of your windows, furniture, paper or hard floors that feel clammy, steam or moisture on mirrors, or the evidence of mold/mildew in the corners of a wall. If you suspect too much humidity, take a reading and then operate a dehumidifier to remove that excess moisture.
Even if your manufacturer recommends changing the filter every three months, your humidifier's filter may not last that long. If your water has a lot of mineral content, scale can easily build up in the filter and hamper its operation. Other factors can also affect filter life including if water has been left standing in the unit. Even if you changed the filter last month, if you detect a foul odor from your humidifier, chances are that it needs a filter change and/or cleaning. Be pro-active when it comes to humidifier care and keep a spare filter on hand.
14. What's the White Dust Collecting Around the Humidifier
That white dust is mineral deposits from the water that are discharged with the moisture to the room and collects as dust near the output grate of the unit, as well as on items close to it. Some find that using demineralizing tablets will help, but the best way to reduce scale deposit if you have hard water, is to use distilled water in the humidifier. While this is not always possible nor economical, if your unit is small, it may be worth considering. Otherwise, you may need to clean your humidifier more often, as well as vacuum dust around it.
Also see: Ultrasonic vs Evaporative Humidfiers for more on humidifier dust.
While it would seem logical to use a warm-mist humidifier in winter and cool-mist during the hot summer, it's more often a matter of preference for many. Warm or cool depends on which benefits you the most when it comes to breathing or reducing coughing. If you have problems breathing in a sauna - you'll likely find it difficult with a warm-mist humidifier. On the other hand, if a sauna is comforting, then it might be the best choice. Either type will add moisture to a home, but your doctor may recommend one over the other. If you want a medicated vapor, a warm-mist humidifier is designed for this purpose, but cool-mist is the most common type of humidifier.
Some do think that a warm mist humidifier is safer to operate especially if there are small children in the home and for good reason. A warm mist humidifier contains hot water in the tank as well as a hot heating element, both of which could pose a risk of scalding or burns if a child came into contact with these. There are some standard safety steps when it comes to humidifier use and with proper care, any humidifier can be safe. You may also want to read these general Appliance Safety Tips and be pro-active to keep your family safe.
It's a great idea to compare humidifier prices and read consumer reviews before buying a humidifier. However, humidifier consumer reviews are rather mixed. The most influencing rating factor seems to be operating noise, followed by how much cleaning a unit needs. Keep in mind that the term 'quiet' is subject to interpretation - what one may find quiet, another might find loud. And given that several factors can cause a humidifier to need cleaning, consumers tend to have different experiences when it comes to scale build-up or general humidifier cleaning - and this should be expected.
Likewise, dehumidifier reviews can also be mixed mainly due to consumers choosing an inadequate capacity for their moisture problems. But you can learn a lot about the design features or constraints of certain dehumidifiers by reading consumer reviews.
Trying to decide whether you need a humidifier or not? If you're an allergy sufferer, chances are you need one:
If you're trying to decide on humidifier type or portable vs room models, read: Portable vs Whole House Humidifiers
Learn the difference between a Hygrometer and a humidistat.
Read more about air quality appliances.