Humidifier Buying Guide

Humidifier Buying Guide

Dry climates, winter air, and artificial heat can lead to dry skin and irritated nasal and sinus membranes. Room humidifiers help to restore moisture to dry sinus and nasal membranes by adding moisture to the air. By restoring humidity to healthy levels you not only can alleviate symptoms from dry air, like eczema irritation, dry skin and night time cough (often experienced by asthmatics), but also promote a healthier environment for the wood and other things in your home that can be damaged by air that is too dry. Additionally, proper humidity also helps to keep dust down, literally. When the air becomes very dry, particles, like dust more easily become suspended in the air you breathe. Humidity can help reduce their buoyancy and cause them to settle of the floor, out of the air.

Amongst all humidifiers there exists one basic division - cool mist or warm mist. You can choose between any number of warm mist humidifiers and cool mist humidifiers, and all do the same thing, relieve the symptoms associated with dry air. Some units like dual mist humidifiers are capable of producing both temperature mists. Note though, that often dual mist models do NOT emit a steam as hot as a standard warm mist humidifier.

If you are concerned with how the water is released into the air, there are again options. Ultrasonic, evaporative, boiler, impeller, and air washers are all types of technologies/styles of humidifiers. Beyond this, there are features, warranties, initial cost, and maintenance costs to consider before purchasing. With all of these options, how do you decide which humidifier is right for you? That's where we come in to help you sort through this jungle of home humidifier options.

  Cool Mist vs. Warm Mist Humidifiers

Air O Swiss 7144 HumidifierAs the most basic division of humidifiers, there are cool mist and warm mist models. Cool mist humidifiers are typified by the lack of any type of heating used in the pre-, post-, or during the humidifying process. Most humidifiers available today are standard cool mist humidifiers. Warm mist humidity is generally created in one of two ways. Either the water is boiled, like in a traditional boiler style humidifier, or the water is warmed. The latter is a common feature of dual mist ultrasonic humidifiers. Those that warm generally lose most of the heat by the time it exits the machine. So, is one better than the other?

This humidifier choice is largely a matter of personal preference. As Dr. Henry Bernstein, confirms, "I do not have a preference between a warm or cool mist humidifier since both accomplish the same thing - getting moisture into the air." Warm mist can be more soothing for stuffy noses and sinuses. If young children are around, the hot water and steam can be dangerous. A true warm mist humidifier can also make the air feel warmer and holds onto heat better, and warm mist humidifiers can actually help lower your utility bill during the winter by changing the heat index. Simply put, the body loses heat faster when the air is dry.

In reality, either style of humidifier can actually make you feel warmer. The human body is constantly shedding moisture, and as moisture evaporates, it cools. This is also why many people refer to a "dry heat" as a positive thing on a hot day. The same principles hold true for humidifiers. By putting moisture back into the air, it can help make you feel warmer by slowing the process by which the body naturally loses moisture and heat.

  How Humidifiers Work

How Home Humidifiers Work

As far as the method of getting moisture back into the air, there are four basic technologies. The most simple of these is found in evaporative humidifiers, which adds moisture to the air using a fan that draws air over a wet wick. The air collects the moisture and is then dispersed throughout the room. Newer evaporative-style humidifiers are much quieter and more compact than their loud, bulky predecessors. Evaporative humidifiers should be cleaned regularly to ensure the tank is hygienic, and this process also helps to remove any scaled or sediment from hard water. Though cleaning is required, this type of humidifier can be used with any type of water - softened, hard, or distilled. Evaporative humidifiers often have the advantage of being "top-fill" models, which means you can simply refill them with a pitcher of water, often while they continue to operate. This type of model is generally available as a cool mist humidifier. Effective and easy to operate, an evaporative humidifier doesn't produce a visible mist like other styles we'll discuss. Stadler Form currently offers a few solid models that fit into the evaporative category.

Air-O-Swiss S450 Is a Boiler Style, Warm Mist Humidifier But Won't BurnThe second type, a boiler style humidifier, does as the name implies - boils the water turning it into a very warm steam mist. Many people like this style of humidifier for a few reasons. First, it kills germs, bacteria and other microbes in the water. Second, many of these models have a medicine cup where you can use a vapor style medicine, like Vicks, with the humidifier. Like evaporative humidifiers, boiler style units can be used with any type of water. Lastly, because a boiler style humidifier emits warm mist, it won't cool the temperature of the room when used during the winter months and is more soothing to many people. The drawback to this model is that, the steam can burn, and with small children or pets, it can possibly be a burn or fire hazard.

In place of actually boiling the water, many manufacturers have opted for a safer approach by simply preheating the water before turning it into mist. While the moisture isn't as warm as with models that truly boil (water coming out is generally right around 100 degrees F.), it is safer for those with small children in the home. This type of humidifier, is what is considered a dual mist humidifier, since it can emit slightly warmed and cool mist but is not a true boiler humidifier.

Close Up - Air O Swiss Brass Ultrasonic DiaphragmCurrently, the most popular style of humidifier is ultrasonic. This type uses high-frequency vibrations, created by a small brass diaphragm to break water into micro-fine droplets that spray this cool fog of mist into the air. There are a couple advantages to this type of humidifier. First, there's no boiled water. Second, these humidifiers are nearly silent. The only exception to this is with some less expensive models that use a fan, which occasionally need to be lubricated. Next, ultrasonic humidifiers have the highest output of all the types available. Under severely dry conditions, you can literally put more than three gallons of moisture back into the air with certain ultrasonic humidifiers. Lastly, the ultrasonic vibrations kill many microbes by disrupting or destroying their cell walls.  Air-O-Swiss humidifiers are our leading brand in this category. With a variety of models, sizes, and options available, ultrasonic humidifiers dominate their product line. Pure Guardian Ultrasonic HumidifierPure Guardian and Crane also makes a variety of ultrasonic humidifiers. Stadler Form also has a few ultrasonic models available.

Ultrasonic humidifiers do have some unique features and require some maintenance. Some ultrasonic models come with silver ions embedded into the water tanks or use activated carbon or ionic silver accessories as natural antimicrobial agents. Scale from hard water can sometimes be a problem, but descaling agents or a simple mix of water and vinegar also removes this. Nearly all ultrasonic humidifiers can be equipped with a demineralization cartridge. This helps to remove hard water mineral content and prevent the build up of scale. In terms of maintenance, like other models, regular cleaning keeps them hygienic and free of mineral scale.

Air-O-Swiss 2055A Air WasherImpeller humidifiers use constantly rotating discs to break the water into fine drops that enter the air. Humidifiers that use sets or an array of discs like this are also referred to as air washers. This is because the rotating discs in the air washer also capture dust and other impurities in the air, essentially "washing the air," and by using an array or set of discs, it increases the surface area for both cleaning the air and humidifying. Do not confuse an air washer with an air purifier. The air cleaning aspect of an air washer is nowhere near as efficient as a HEPA air purifier, but this is a small added bonus of this type of humidifier. In terms of humidifying, the effectiveness is similar to that of an evaporative unit but not quite as robust as many ultrasonic models. This type of humidifier works well with any kind of water, but like the others does require some regular cleaning.

Other Factors to Consider

Germ Protection Germ Protection: Is the water boiled to kill germs? Does it have another antimicrobial measure like a UV light or silver ions? If not, your air will not only be humidified, but it may also be contaminated with bacteria and mold.
Ease of Use Ease of Use: We recommend that you clean all humidifiers regularly to prevent mold growth. Some are easier to clean than others. The Air-O-Swiss 2055A Air Washer gets first place in this category thanks to its dishwasher-safe discs. Other models can be easily cleaned with a mild soap and water and have scale removed with a descaler or mix of vinegar and water.

Operating Range and Water Capacity
Operating Range: It's important to make sure that the humidifier can cover the area of the room where it will be placed. Placement should be central and not near a heating vent. Most humidifiers typically cover anywhere from 250 up to 800 sq. ft.

Water Capacity: How often will you have to refill the tank? Refilling the tank can be a very simple task to something that is more chore-like. This mostly depends on the type of humidifier you choose, but in addition to this, there's a lot of variance in water tank capacity. Larger ones can hold up to over 2 gallons on water, while more standard sized models hold from one to one and a half gallons.

Operating Costs Operating Costs: How much will it cost to run the humidifier? Generally, impeller humidifiers and ultrasonic humidifiers use less energy. You should also consider costs of replacement parts, such as UV light bulbs, demineralization cartridges, and Hydro Sticks. If you're going to purchase a new humidifier, you can save money on shipping costs by purchasing several replacement parts with the initial order.

Noise Level Noise Level: How loud will the humidifier be? Traditional evaporative humidifiers were loud because of the fan, but most models now are fairly quiet. With some the noise level will be similar to a box fan on low speed, while other models, particularly ultrasonic home humidifiers, are so quiet, you might have a hard time determining if they are actually on. Perhaps that's an exaggeration since a stream of visible mist is hard to miss, but they are extremely quiet.

Humidistat & Other Humidifier Options Humidistat Options: Digital room humidifiers often have a built-in hygrometer (humidity gauge) to give you a fairly accurate assessment of the relative humidity in your home. Most models come with some type of integrated humidistat, which allows you to set a specific humidity set point or goal. If you need tight control over the humidity level in your home, it is always wise to purchase a separate humidity gauge as they can sometimes provide a truer reading than from a humidifiers integrated gauge (the integrated are often graduated in increments of 5%).

Manufacturer's Reputation Manufacturer's Reputation: A manufacturer's reputation and the experiences of past customers deserve consideration in your decision. Certain manufacturers and products are highly respected in the industry for a reason - and the same goes for products which have garnered less respect. Air-O-Swiss humidifiers are made by Plaston, Europe's leading supplier of plastic packaging systems and air treatment systems.

Humidifier Warranty Warranty: Humidifier warranties generally vary between one to three years. The more expensive models and brands often offer a three year warranty while less expensive models generally stick with a single year warranty. This can also vary by the type of humidifier you buy. Evaporative models often last a very long time, so it is not uncommon to see a longer warranty period attached to them.

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Why buy from Customer Testimonials
My son has always had a nagging cough when the weather gets colder, that persists all winter long. The Vornado Humidifier  seems to have helped him feel better, and I don't hear nearly as many late night coughing fits. Thanks!
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