Update Bulletin No. 649
most home centers
and hardware
stores. If you
have small children that may have
access to rooms
with the humidifier Typical evaporator
in them, it would be wise to avoid the steam
mist (vaporizer) design. The steam outlet
may scald a child’s hand. I use a quiet
ultrasonic model in my bedroom at night and
an evaporative type near my corn/pellet stove
in my living room.
you for
your interest
in writing to me about
using a humidifier to keep
your house more comfortable, protect it from damage and lower your heating bills. A humidifier
Jim Dulley
lowers your heating bills
by allowing you to set your furnace thermostat lower without feeling chilly. When the
room air is overly dry, the moisture from
your skin evaporates quickly and this cools
you similar to sweating. The chart below
will give you a rough idea of the capacity of
humidifier you will need. Very cold climates often need slightly larger humidifiers
and very mild areas need slightly smaller
The evaporator designs (pictured above)
generally can have the greatest moisture output. Most larger console models use this
design. A large capacity console model
can easily humidify an entire house. Even
without the furnace blower circulating
the air throughout the house, the
moisture will naturally migrate
to all the rooms.
On the following pages, I have
listed manufacturers of the highest quality humidifiers for home
use. Page four shows an excellent
description of the advantages and disadvantages of the most common designs of humidifiers you will find at
Even though many humidifiers have antimicrobial treatments
on the wicks, filters and plastic hous-
Humidification Selection Guide
Construction of Residence
Size of Residence in Square Feet
Water Output Capacity, Gals./24 Hours
Tight — well insulated, vapor barrier, tight storm
doors/windows with weatherstripping, dampered
Average — insulated, vapor barrier, loose storm
doors/windows, dampered fireplace
Loose — little insulation, no storm doors/windows,
no vapor barrier, undampered fireplace
NOTE: If there is uncertainty as to the type of home construction, the values shown in the average
category may be used.
*Humidification not necessary to maintain conditions of 70oF (21.1oC) and 30 percent relative humidity
An amount of approximately 2 gallons per 24 hours provided by internal sources of humidity (based on
a family of four) has already been deducted from the above values.
Maximum Indoor Humidity Level to Avoid Window Condensation
Outdoor Temperature
Maximum Indoor Humidity
Level - Single Pane - %
Maximum Indoor Humidity
Level - Double Pane - %
oF and a wind speed of 15 miles per hour.
The above chart is based on an indoor temperature of 70
this only as a guideline. The actual humidity level where condensation forms depends on your specific
window design, special coatings, thickness of air space, and type of gas in between glass panes. The
frame may also begin to sweat before the glass itself.
ings, it is a good idea to clean them regularly
per the manufacturer’s instructions. The
last thing you want is to have mold spores or
bits of bacteria being introduced into the
room air.
In all but the mildest climates, shoot for
a humidity level just slightly less than the
level that causes window condensation. On
colder days, you will have to set the humidifier to run less or get replacement windows
with more efficient glass to avoid condensation. If you have hard water in your area,
you may find a white powder near an ultrasonic humidifier. This is the hard water ion
deposits as the water evaporates in the air.
The prices of humidifiers can range
from as little as $20 for small tabletop
models to more than $100 for large decorative console models. You can find them at
many discount and home center stores and
they are often on sale. Also check the
manufacturers’ web sites for specials. For
example, Holmes Products has some
discounted special items which
they sell online.
Use and Care Recommendations from
The Environmental Protection Agency
• Empty the tank, wipe all surfaces dry, and refill the water in portable humidifiers daily to
reduce any growth of microorganisms; follow
the mfgs. instructions for changing water in
console humidifiers. Unplug the unit from the
electrical socket first. Use water with low mineral content to prevent the buildup of scale and
the dispersal of minerals into the air.
• Clean portable humidifiers every third day.
Empty the tank and use a brush/scrubber to
clean it. Remove any scale, deposits, or film
that has formed on the sides of the tank or on
interior surfaces, and wipe all surfaces dry.
Unplug the unit. Follow the mfgs. suggestions
on the use of cleaning products or disinfectants. In the absence of recommendations,
clean all surfaces coming in contact with water with a 3 percent solution of hydrogen peroxide. If you use any cleaning or disinfecting
agent, rinse the tank thoroughly with several
changes of tap water to prevent dispersal of
chemicals into the air during use.
• Keep steam vaporizer humidifiers out of the
reach of children. Steam and boiling water may
cause burns.
• Do not permit area around humidifier to become damp. If dampness occurs, turn the output volume down. If output volume cannot be
turned down, use the humidifier intermittently.
Do not allow absorbent materials, such as carpeting, drapes or table cloths, to become damp.
• If water condenses on windows, walls, or pictures, either relocate the humidifier, lower its
humidistat setting, or reduce its use.
Update Bulletin No. 649
page 2
Selected Manufacturers of Portable Humidifiers
5800 Murray St.
Little Rock, AR 72209
(800) 826-2665
690 Series
5.5 gallons
2,300 sq. ft.
11.0 gallons
space saver
6.0 gallons
1,700 sq. ft.
8.0 gallons
3.2 gallons
1,000 sq. ft.
5.0 gallons
1.7 gallons
560 sq. ft.
2.3 gallons
1.6 gallons
750 sq. ft.
3.3 gallons
Features - The “690 Series” has a variable-speed fan to spread the moist air efficiently in the air. There are concealed castors on the bottom of the unit so
you can move it about easily. The units have two water bottles each that hold 2.75 gallons. The water bottles come with a refill hose making them easy to
fill. There are refill lights that indicate when bottles need refilling. The control panel is hidden so the lines remain clean on the cabinet. The cabinet is
available in a driftwood or light oak woodgrain finish. The automatic humidistat senses when air needs more moisture and turns the fan on and off as
needed. The power pack is removable for cleaning. Model “336-500” has three-speed operation, including a quieter setting for nighttime sleeping. The
humidistat automatically maintains the desired humidity level. There are two water bottles that are easy to carry and fill. Model “DP3 200” is an air purifier
and humidifier in one unit. It cleans a 12' by 14' room 4 times per hour. It has Clean Air Delivery Ratings (CADR) of 110 for pollen, 125 for dust, and 90 for
smoke. Also removes bacteria and pet dander. There is a lock-on feature to run only the air purifier during the summer. This unit also has a quiet
nighttime setting and an automatic humidistat. Model “826-800” has a special, compact space saving design for whole house humidification. The
automatic humidistat turns the unit on and off to maintain desired humidity level. The refill light reminds you when you need to add water. The castors
allow you to move the unit from room to room easily. There are many other models to choose from.
PO Box 4100
St. Louis, MO 63136
(800) 237-6511 (314) 553-2000
4.6 gallons
2,700 sq. ft.
13.0 gallons
3.4 gallons
1,300 sq. ft.
6.0 gallons
1.2 gallons
600 sq. ft.
2.5 gallons
Features - Model “HD1300W” has an automatic humidistat that keeps humidity at the level you select. It is available with a bleached oak woodgrain accent
with a white cabinet. It has two easy-to-fill bottles that are 2.3 gallons each. Equipped with four easy-to-roll castors so you can move the unit easily. A fill
light tells you when water is low and the unit shuts off automatically. The unit has variable speed air flow control. Available with single or dual fan control.
The filter system is a honeycomb that floats in the water reservoir and is treated with a special compound to retard bacterial growth — keeps minerals and
solids out of the humidified air. Model “HD6000” has three-speed air flow control for your comfort. Equipped with two easy-to-fill 1.7 gallon bottles. Model
“HD230” can be used during the fall and winter months as a humidifier to keep moisture in the home and then use it during hot summer days for a fan. It is
equipped with three-speed air flow control for comfort. The unit has four rubber feet so it can be placed safely on a dresser or table without scratching the
furniture. The grill can be rotated to get the moisture where it is needed. There are three locations on the top of the unit where the cord can exit that allows
flexibility of unit placement. There are many other models available.
1801 Commerce Dr.
Piqua, OH 45356
(800) 233-5921
warm mist
2.2 gallons
600 sq. ft.
2.5 gallons
3.4 gallons
700 sq. ft.
2.3 gallons
1.5 gallons
650 sq. ft.
2.8 gallons
Features - The "HM3655" humidifier runs up to 36 hours without refilling, allows you to select the exact humidity level you prefer and lets you know when
you need to replace the filter. The Microban antimicrobial protection helps keep your humidifier clean. The "HM508-UC" unit runs up to 22 hours on a single
fill. It has a removable tank for easy filling and an automatic shut-off when the tank is empty. It has a two-speed fan to control the amount of
humidification. The "HM485" ultrasonic unit is whisper-quiet.
2500 Frisco Ave.
Memphis, TN 38114
(800) 971-3267
2.0 gallons
1,175 sq. ft.
2.0 gallons
3.0 gallons
1,475 sq. ft.
3.0 gallons
2.5 gallons
1,350 sq. ft.
2.5 gallons
3.5 gallons
1,600 sq. ft.
3.5 gallons
Features - Model "33202" has a night light that illuminates the water tank with a soft glow and a permanent wick filter that never needs to be replaced. The
filter has a special bacteria guard treatment that protects against the growth of microorganisms so germ-free moisture is sent out into the air. Special
antibacterial and antifungal agents are molded into the plastic parts to prevent the growth of any microorganisms or bacteria. The humidifiers provide water
as needed to eliminate stagnant water around the filter that can breed bacteria and germs. The automatic moisture regulation system automatically adjusts
the output to the moisture in the air. Model "33250" also has an adjustable humidistat and the permanent wick filter to maintain your desired humidity level.
An indicator light tells when the humidity level has been reached. There are two fan speeds to also help adjust the humidity output rate. The units will
automatically shut off when the water reservoir is empty. A refill light also alerts you to this situation. The humidifiers are designed to only allow a minimal
amount of water out of the tank. Other models available have a replaceable paper wick filter element. There is a five-year limited motor warranty.
250 Turnpike Rd.
Southborough, MA 01772
(800) 332-1110
Honeywell HWM-2030
warm mist
Honeywell HCM-2000
Honeywell HCM-3060
Robitussion DH-750
cool mist
warm mist
Duracraft DH-890
cool mist
Duracraft DH-910
warm mist
1.8 gallons
700 sq. ft.
3.0 gallons
2.0 gallons
1350 sq. ft.
4.0 gallons
4.4 gallons
1950 sq. ft.
6.0 gallons
2.0 gallons
not available
2.5 gallons
750 sq. ft.
2.0 gallons
900 sq. ft.
2.0 gallons
.80 gallons
Features - The “Honeywell” models have an adjustable humidistat that maintains the moisture level that you select. The units will turn themselves off
automatically when the tank is empty. Model “HCM-3060” has three different moisture settings to meet your personal preferences. It is equipped with
power and desired humidity lights so you know that the unit is operating correctly. It has two clear, removeable water tanks that are easy to carry and fill.
Model “Duracraft DH-910” has a dishwasher-safe medicine dispenser. It has a removable clear water tank, the handles are no drip and can be carried and
filled easily. It shuts off automatically if the tank is empty, removed or tipped over accidentally.
Update Bulletin No. 649
page 3
Selected Manufacturers of Portable Humidifiers
KAZ, cont'd.
Kaz 3400
Vicks V3500
SafetyLight 2200
2.0 gallons
2.0 gallons
2.0 gallons
1,000 sq. ft.
2.5 gallons
warm steam
2.0 gallons
HealthMist 4220
cool mist
2.0 gallons
1,000 sq. ft.
2.0 gallons
2.5 gallons
Vicks V5100
1.5 gallons
600 sq. ft.
1.7 gallons
Features - The evaporative units can be filled without removing the cover. The water level indicator tells you when to refill and how much water to add. It is
equipped with a two-speed switch. The warm steam unit is a vaporizer and has a chamber for an inhalant. It has patented safety vents that regulate the
steam flow, preventing overboiling. The triple-wall construction maintains the reservoir water at a safe temperature. The carbon electrodes operate
efficiently in any water condition, they will not rust or corrode. The outer cap is cool-to-the-touch so it can be handled safely. The unit shuts off
automatically when the water reaches a minimum level. Equipped with a night light for additional safety and convenience. The cool mist units have an
air-cleaning filter that removes dust, pollen, odors, and tobacco smoke from the room air, removing 93 percent of particles as small as pollen. Equipped
with a lifetime-lubricated motor. There is a directional spout/grill that varies the vapor direction both horizontally and vertically. The “HealthMist” features
high and low vapor settings, the vapor is whirled through a vortex chamber to provide a superfine mist for quicker evaporation. The “Vicks V3500” has a
removable tank so it is easy to fill. The tank bottom is sloped for complete emptying during operation. The wicking filter has a built-in bacteriacide to clean
the air and trap minerals, pollutants and bacteria from the water. Kaz also offers a personal humidifier that can be used almost anywhere. See below for
picture and features of the personal humidifier.
820 Lincoln Ave.
W. Chester, PA 19380
(800) 233-0268 (610) 692-7400
1.5 gallons
1,100 sq. ft.
2.5 gallons
1.75 gallons
1,500 sq. ft.
3.0 gallons
2.0 gallons
1,800 sq. ft.
4.0 gallons
4.5 gallons
3,200 sq. ft.
9.0 gallons
6.0 gallons
3,800 sq. ft.
12.0 gallons
6.0 gallons
4,200 sq. ft.
12.0 gallons
Features - These humidifiers have a pump operated system that allows water to be constantly moving, similar to a waterfall. This movement of water
eliminates problems associated with standing water such as a breeding ground for microorganisms. The humidifiers have a clear window which lets you see
the water circulating. It also lets you know when the unit needs to be filled. The console models have castors so they can be moved easily on any type of
surface. They have three speeds, an adjustable humidistat with indicator light and two easy to change evaporative filter pads. Filter pads last about six
months. Consoles available in grey or wood grain. See illustration and features on page four.
100 Forest Dr.
Greenvale, NY 11548
(800) 775-4552 (516) 484-2600
warm mist
2.0 gallons
400 sq. ft.
3.5 gallons
2.5 gallons
4.0 gallons
Features - The humidifiers have a special dual-germicidal process that combines the germ-killing power of ultraviolet light and vaporization — kills 99.99
percent of bacteria, molds and spores that can breed in tap water. Model “GF-350” has a stainless steel hot water reservoir with a stainless steel scraper
included. It will humidify for two to three days continuously without a refill. The "GFH-150" humidifiers and other models have a built-in medicine cup for
use of medications during respiratory illnesses. Mineral absorption pads are included to minimize mineral buildup. These humidifiers produce absolutely
no white dust and have silent operation. Three-year limited warranty.
415 East 13th St.
Andover, KS 67002
(800) 234-0604
Vortex Humidifier 30
2.8 gallons
850 sq. ft.
2.8 gallons
4.2 gallons
1,750 sq. ft.
4.2 gallons
Vortex Humidifier 40
Features - The patented spill-proof bottle design allows for easy filling and carrying. The humidifiers are equipped with three fan speeds to allow for precise
humidity control. The units have a five-year warranty. Both humidifiers have large enough tanks for uninterrupted 24-hour operation. Both units use the
wick filtering system; by pulling air through the wick the water is evaporated putting moisture into your home.
4310 Del Ray Ave.
Marina Del Ray, CA 90292
(800) 405-2943
Ionic Air Washer
1.9 gallons
600 sq. ft.
3.0 gallons
Features - The “Air Washer” humidifies by drawing air through water. This process eliminates small airborne particles just like the outdoor air is cleaned by
rain. The air is simultaneously humidifed by a special dishwasher-safe disc which eliminates the need for any replacement filters. It is equipped with an
antibacterial safety system and two modes of operation. It is ideal for use between autumn and late spring pollen seasons.
Humidifiers by Kaz
The warm steam vaporizers boil the water
and produce a pure steam vapor which is released into the air. The vapor is bacteria-free
and leaves no white dust. The vaporizer shuts
off automatically when the water reaches
minimum level.
The outer cap is cool to touch for safety.
There is a night light that provides additional
safety and convenience.
Compact, lightweight the personal humidifier
can be used anywhere. The dual-voltage unit operates with a plastic water bottle. This model fits on a
nightstand and travels well. It is whisper-quiet and
adds beneficial mist to dry indoor air.
It has a directional mist outlet and two output
settings. This allows you to control the direction
and amount of mist "plume." Unit can be converted
to other voltages for worldwide use.
Update Bulletin No. 649
page 4
Selector Guide for Various Humidifier Types
How it Works
Water is drawn into a belt, wick
or filter through capillary action.
A fan pulls air through the filter,
allowing the water to evaporate
and sends it into the room.
• Uses little energy.
• Uses tap water.
• Easy to clean.
• No spray, unlikely to spread
bacteria and white dust.
• The fan and airflow can be noisy.
• Periodic filter replacement adds to
operating cost. Filters often available only
from manufacturer.
• Must be cleaned regularly to prevent
growth of undesirable microorganisms.
• Removes heat from the room.
Impeller or Cool Mist
The impeller and fan assembly
dips into a water tank. As the
cone spins, it pumps water
upward. The fan blades throw
water droplets out a nozzle and
into the air.
• Uses little energy.
• Needs fewer refills than other
• Tank is very easy to clean.
• Very inexpensive to buy.
• Can spew microorganisms along with
• Can splatter water.
• Can emit white dust if used with hard tap
water, it needs distilled or soft water or a
demineralization cartridge. One year's
running cost can exceed purchase price.
• Sloshing noise from the fan and impeller
assembly can be annoying.
Steam Mist or Vaporizer
Water flows into a small heating
chamber and it is kept at the
boiling point. As the water boils,
it releases moisture through a
spout and into the air.
• Uses tap water.
• Requires no filters.
• No moving parts.
• Boiling water kills
microorganisms; water vapor is
• Emits little or no white dust.
• High energy consumption.
• Heating element may need extra
cleaning to remove any buildup of hard
water minerals.
• Mist and boiling water from tipped over
tank can scald.
• Can emit bits of dead microorganisms
causing allergic reactions.
• Noisy.
Warm Mist
Warm mist humidifiers are a type
of steam vaporizer humidifier in
which the steam is cooled before
exiting the machine. A fan in the
spout mixes cool air with the
steam which produces mist
somewhat warmer than room air.
• Uses tap water.
• Requires no filters.
• No moving parts.
• Boiling water kills
microorganisms; water vapor is
• Emits little or no white dust.
• Less risk of scalding from mist.
• High energy consumption.
• Heating element may need extra
cleaning to remove any buildup of hard
water minerals.
• Can emit bits of dead microorganisms
causing allergic reactions.
• Noisy.
• Boiling water from tipped over tank can
Water flows from a reservoir to a
transducer and nebulizer (small
electronic components).
Nebulizer oscillates about 1.7
million times a second, churning
the water into a cool mist.
• Uses little energy.
• Releases very few
microorganisms into the air.
• Quiet.
• Emits annoying white dust if used with
most tap water.
• May require soft or distilled water or a
demineralization cartridge.
• Very hard water can leave hard to
remove mineral deposits on nebulizer.
• Can emit bits of dead microorganisms
causing allergic reactions.
Evaporative Humidifier (Model
33202) from Hunter
• NiteGlo night light
illuminates the water tank with a soft
• Automatic shut-off
when tanks are
• Refill light signals that
humidifier needs to be refilled
• Adjustable humidistat maintains your desired
humidity level, light indicates when level is
• Automatic moisture regulation system automatically adjusts output to the moisture in air
• Three speeds to control moisture output rate
• Tank specially designed to simplify filling,
make carrying easier
• Five-year limited motor warranty
Ionic Air Washer AAT2003
from WindChaser
• No replacement filters
• Easy to clean, dishwasher safe disks
• Antibacterial safety system
• Two whisper quiet operating modes
• Detachable water tank with handle
• On/Off indicator
• Water output - 3 gallons
• Water capacity - 1.9 gallons
• Suitable for 600 sq. foot room
The Ion Humidifying
Air Washer washes and humidifies the air by drawing
air through water. This process eliminates small airborne particles. At the same
time the air is humidified
by a disc which eliminates
the need for any replacement filters.
Evaporative Humidifier
(Model 1128) from Lasko
• 9.0 gallon output
per day
• Humidifies up
to 2,000 sq. ft.,
ideal for multiple rooms.
• Water capacity
— 41/2 gallons
• Three control
speeds with on/
off indicator light
• Adjustable humidistat with indicator light
• Removable clear water reservoir with dual
handle for easy filling
• The clear-view water window shows the unit
working — waterfall
• Castors for mobility on any surface
• Evaporative filter pad is included
• Continuous pump-driven circulation
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