|Tabletop Humidifiers – Also called portable humidifiers, tabletop units are ideal for humidifying a single room. The typical design plugs directly into a wall and pulls water from a refillable tank. Tabletop units are lightweight, making it very simple to move them between rooms. Small tabletop units are sometimes called compact humidifiers.|
|Tower Humidifiers – If you prefer to set a humidifier on the floor instead of a table, consider a tower design. These are perfect for humidifying a medium-size room. Some tower models need refilling less frequently than tabletop units.|
|Console Humidifiers – Like tabletop and tower humidifiers, console units are self-contained systems with refillable tanks, but they offer considerably more power. Console units are designed to humidify several rooms at a time, and they generally have larger tanks, which you don’t have to refill as often. Consoles are bigger and heavier than tabletop and tower models, but can still be moved between rooms.|
|Whole-House Humidifiers – Also known as in-duct or online humidifiers, whole-house units introduce moisture directly into a forced air heating system. In the typical design, air blows through a wet wick, into a duct leading from the furnace. When the forced air system is running, it carries the moist air to every room in the house. Most whole-house humidifiers connect directly to the household water supply, which means you never need to refill them. They also have the lowest energy demands of the three humidifier sizes. Whole-house units require professional installation and will only work with a forced air heating system.|
|Cool Mist Evaporative Humidifiers – In this system, a fan blows dry air through a wick, which absorbs water from a refillable tank—or, in the case of a whole-house unit, the household water supply. Cool water from the wick evaporates into the air, boosting the humidity level. The wick also acts as a filter, removing any impurities in the water. Most whole-house units are evaporative humidifiers, and the design is common in tabletop and console models. Maintenance for console and tabletop evaporative humidifiers includes refilling the water tank 1-2 times a day, depending on usage, and replacing the wick every two months or so. With a PermaFilter evaporative humidifier, you can clean the wick instead of replacing it regularly. Evaporative models have relatively low power demands.|
|Warm Mist Humidifiers – Also known as steam humidifiers, these models work like a tea kettle. A heating element boils water from a refillable tank or the household water supply, generating steam that humidifies the surrounding air. Like evaporative humidifiers, warm mist humidifiers remove impurities from the water, producing clean saturated air. One key benefit of this design, especially during the winter, is the steam helps keep rooms warm. Since they don’t include a fan, warm mist humidifiers are very quiet. Tabletop and console models require you to refill the water tank periodically, but there’s no wick to replace. However, it may be necessary to clean the unit regularly, as impurities from the water can build up in the tank.|
|Vaporizers – Small, low-output warm mist humidifiers are called vaporizers. These units have a built-in water reservoir, rather than a removable tank.|
|Ultrasonic Humidifiers – In this system used in many tabletop models, a metal diaphragm vibrates at ultrasonic frequencies to break water up into a cloud of tiny droplets. Ultrasonic humidifiers are the quietest of the available systems, and have relatively low power demands. They do not remove all water impurities, but some include “demineralization cartridges” that filter out much of this material. It’s necessary to refill the tank regularly, but there is no filter to replace. Ultrasonic humidifiers generally produce a cool mist, but some models include a heating option that helps keep the room from getting too cold.|
|Cool Mist Impeller – In this tabletop design, a spinning disc generates a fine mist of cool water. Like ultrasonic humidifiers, impeller models are quiet and don’t use much power. They do need to be refilled, but there aren’t any filters to replace. Since impeller models don’t remove water impurities, it’s best to fill them with distilled water and clean the tanks regularly.|
• Output per Day – The maximum amount of water the humidifier will add to the air per 24 hour period. Output
is the standard measure of a humidifier’s power, which determines how many rooms it can humidify. Some
models may include a square footage or room number recommendation on the label as well. Refer to the
chart below for general output ranges and corresponding applications.
• Tank Capacity – The amount of water the refillable tank can hold, listed in gallons. Typically, you need to
refill larger tanks less frequently than smaller tanks.
• Run Time – How long the humidifier can run on a full tank of water.
|Portable Dehumidifiers – These models work the same basic way as a window air conditioning unit. A fan blows moist air from the room across cold refrigerant-filled coils, which cool the air, causing the moisture to condense into water droplets. In a typical design, the water collects in a bucket, which you need to empty periodically. Many models also have a hose attachment, which lets you drain the water directly into a sink or basement drain. Unlike an air conditioner, a dehumidifier includes a separate heating coil that warms the air again before expelling it into the room.|
|Whole House Dehumidifiers – These units work the same basic way as portable models, but have the extra power necessary to dehumidify several rooms at once. Typically, a whole-house unit can service about 3,000 square feet of living space. Some models connect to the ductwork in a central air or heating system, while others are self-contained systems. Some models can operate in either mode. Whole-house units empty collected water into a drain leading outside the house, rather than a refillable bucket. Models that connect to central heating and air system usually require professional installation.|
• Capacity – The volume of water the unit can remove over a set period of time, generally represented as
pints per day. Capacity is the standard rating for dehumidifier power, which indicates the moisture level
and room size the unit can handle. Refer to the chart below to match dehumidifier category and capacity
to suggested applications.
• Bucket size – The size of the water collection bucket. A dehumidifier with a larger bucket can run for
a longer period of time before you need to empty it.