For many reasons:

  • Since the air in your home is always trying to reach its saturation point, it will absorb water wherever it can; from the bodies of you and your children, your pets, your furniture and even your house plants. As a result your skin, throat and nasal passages dry out, leaving you more susceptible to physical discomfort, colds, flu and even infection.
  • Dry air causes dry, itchy skin.
  • Dry air cracks expensive woodwork, floors, artwork and furnishings.
  • Annoying static electricity (caused by dry air) can damage computers, VCR’s and other electronic equipment, requiring expensive repair.
  • Dry air can cause harm to expensive musical instruments like pianos and violins.
  • Dry air causes gaps in window & door frames, letting cold outdoor air in; causing you to turn up the heat and increasing your heating bills! Controlled humidity from the GeneralAire® Elite Steam Humidifier allows you the luxury of dialing the thermostat back & reducing annual heating bills. For example, 68° at 40% relative humidity feels just as warm as 74° at 20% humidity. Setting your thermostat back by as little as three degrees can reduce annual heating bills by as much as 5%.

A humidifier is a tool that helps you keep your home within your desired humidity level. If you keep your humidity levels within that range, you and your home are protected from the effects of having too little, or too much humidity.

Research shows that 40% – 60% relative humidity is ideal. Outside this range, your risk of being adversely affected increases.

We recommend contacting your local certified HVAC contractor, as they will be able to make recommendations for your home based on its age, size & construction. Overall, you can begin to understand which model might be best for your home using the following:

First, determine how much humidification your home needs, known as Gallons Per Day (GPD):

Use the 3-step formula below

Step One

  • Calculate the Total Cubic Feet of Home
  • Total Home Square Footage
  • X Average Ceiling Height

Step Two

  • Calculate the Load (lbs/hr)
  • Total Cubic Feet X Desired Condition Factor (Table Below)
  • X 1.05 for Each Fireplace
Which humidifier is best for me?

Structures Are Not Equal: Windows, Walls, Celling, Roof

Step Three

  • Calculate Gallons Per Day (GPD)
  • Gallons Per Day = Load (lbs/hr) X 2.88

Then, Select Your Unit

Once you have calculated your gallons per day you can then find models that are designed to process that amount of water / accommodate your size of home.

Keep in mind these numbers can vary based on numerous factors, including home construction, the presence and amount of woodwork, if you have a humidor or wine cellar, the presence of fireplaces, the number of floors and more. Work closely with a licensed contractor to determine the best selection for your home.

  • Steam Model 5500=15 GPD (115V) or 29.5 GPD (230V) up to 5,500 Sq. Ft.

The following flow through models Gallons Per Day ratings are based on 120° plenum temperature.

  • Evaporative Models 3200A & 3200M = 12 GPD / Up to 3,200 Sq. Ft.
  • Evaporative Models 4200A & 4200M = 17 GPD / Up to 4,200 Sq. Ft. Evaporative Models 1000A & 1000M = 18 GPD / Up to 3,000 Sq. Ft.
  • 1042LH = 17 GPD / Up to 2,800 Sq. Ft.
  • 1099LHS = 19 GPD / / Up to 3,000 Sq. Ft.
  • 1137 = 19 GPD / Up to 3,000 Sq. Ft.

You might also install more than one humidifier if your home has more than one HVAC system. Many people install a humidifier with each system to reduce the work load on each and more evenly distribute humidification throughout the home.

There are different types of humidifiers:

  • GeneralAire® Steam Humidifiers: The GeneralAire® Steam Humidifier is an electrode humidifier. Steam humidification is produced by passing electric current through water inside a steam cylinder between highly-conductive metal electrodes. Steam output is directly proportional to the conductivity of the water between clean electrodes.
  • GeneralAire® Evaporative Humidifiers: Water is distributed through a water distribution trough resting on top of a Vapor Pad® inside the humidifier. The Vapor Pad® then becomes thoroughly saturated with water. As heated air from the furnace passes through the water-soaked Vapor Pad® the water evaporates and creates humidity. The humidity is moved by the furnace blower motor through the duct system and is distributed to the living quarters of the home.
  • GeneralAire® Fan Powered Humidifiers: Similar to evaporative humidifiers, but with a fan inside the humidifier that pulls heated air from the furnace through the Vapor Pad® to enhance the evaporative process.


We recommend replacing your vapor pad at least once per year. Minerals build up on the vapor pad over time, which in turn:

  • Reduces the pad's ability to absorb water.
  • Prevents the warm air from flowing through the pad (Warm air moving though the water-soaked pad causes the water in the pad to evaporate. It is this process that delivers moisture throughout your home via the home's duct system).

Steam humidifiers require minimal maintenance. As water evaporates inside the cylinder during its normal process of creating moisture via the electrodes, minerals are left behind. Much of these minerals are removed through the cylinder drain; however, some remain and build up on the cylinder walls and electrodes. As lower portions of the electrodes accumulate a thick coating, the water level automatically rises to expose clean electrode surface for maximum electric conductivity. Eventually mineral buildup creates a thick coating along the entire length of the electrodes and little electrical current can pass between them, resulting in poor steam output. The DS50 / DS50LC humidifier senses low amperage and displays the E6 Cylinder Exhausted error code. There is no need to replace your humidifier. At this time, simply replace your steam cylinder.

In high end construction and renovation projects humidification is often required while the structure is being finished, as it helps to protect and stabilize wood floors, trim and decoration. Humidification load in an unfinished structure may be five to eight times higher than a finished one. Elite Steam humidifiers may be operated while construction is underway but you may expect a shortened cylinder life as a result. To ensure your humidifier provides ideal humidification levels once the structure is finished, replace your cylinder.

Humidity Load (also known as Gallons Per Day) has a direct impact on the life of your cylinder. When properly sized to match the square footage of a home, a humidifier will rarely be required to run at full capacity. As a result, water levels inside the cylinder remain lower and buildup of minerals on the entire length of the electrodes takes longer. Thus, the life of your cylinder is greatly enhanced. Conversely, extraordinary installations that require constant operation at full capacity reduce cylinder life. The water level in the cylinder stays generally much higher, and the electrodes become completely insulated by mineral buildup more quickly. Installations like this may result in cylinder life of less than 1000 hours.

Steam cylinders must be matched to the local water conductivity in order to perform as designed. If not familiar with local water conductivity, check using an instrument ( EZTestr11 Conductivity Tester). You can also have your water tested for conductivity by the city or a local contractor.

The following water types are not acceptable:

  • Softened water, as this will lead to foam, electrode corrosion and greatly shortened cylinder life.
  • Water containing disinfectants or corrosion inhibitors, as these are potential irritants.
  • Industrial water, boiler water or water from cooling circuits.
  • Any potential chemically or bacteriologically contaminated water.
  • Heated water.
  • Water with silica deposits.

Overall the humidifier must be supplied with the following water characteristics:

  • Pressure between 20psi and 110psi; or 0.1 and 0.8 MPa (1 and 8 bar)
  • Temperature between 33° F and 104° F; or 1° C and 40° C
  • Flow rate minimum of 0.45 L/min or 0.21 gpm
  • Hardness no greater than 40° fH (equal to 400 ppm3 of CaCO),
  • Conductivity from 125 to 1250 µS/cm
  • Absence of organic compounds

We suggest adding a 1099LHS unit and keeping your currently installed and functioning 1042. Your home size requires more humidification than the 1042 was designed to produce, and two units would be a benefit. Having two humidifiers provides the humidity your home needs without "over-stressing" either unit; thereby ensuring the longest life of both units. If one unit experiences mechanical difficulties, you still have the other humidifier producing moisture for your home. Tip: connecting to the hot water would help increase humidity by approximately 30%. Don't forget to change the vapor pad once per year for optimum performance.

The GFX3 offset mode is used to match the readings of your new GFX3 to other controls in the home (humidity level, outdoor temperature and indoor temperature).

Example: Your GFX3 reads the inside humidity as 25%, but another humidistat inside the home reads 29%. Use the offset feature in the GFX3 to match the other reader. You now have consistency throughout your home.

These instructions can also be found on page 22 of the Elite Steam Installation / Owner's Manual.

  1. Completely drain the cylinder by pressing and holding the "drain" button.
  2. Turn the humidifier off and disconnect the main power.
  3. Remove the cover.
  4. DS Models: Remove steam hose from cylinder, flip up the cylinder holding bracket.
  5. RS Models: Remove 2 bolts of the embedded fan, flip up cylinder holding bracket.
  6. Disconnect the distributor from the cylinder and lift the cylinder out of the unit.
  7. Disconnect the electrical connection from the top of the cylinder, and re-connect to the NEW cylinder.
  8. Install the new cylinder, performing these steps in reverse.

Perform regular, annual maintenance as described below.

  1. Turn off water supply and electrical power to humidifier.
  2. Disconnect the 1/4” water supply line from the solenoid valve.
  3. Remove the small brass filter assembly from the solenoid valve.
  4. Disassemble the filter and carefully pull the screen from the orifice fitting. Clean the mineral deposits from all parts. If the orifice is clogged, it may be opened by inserting a small needle. Reassemble the filter and screw assembly into solenoid valve.
  5. Remove water distributor tube, distributor trough cover, and trough and drain pan. The evaporator pad may be removed from either the top or bottom of the humidifier. Occasionally, lack of adequate clearance may require removing humidifier cabinet. Clean excessive mineral deposits from the distributor trough, trough cover and drain pan. A solution of 1/2 vinegar & 1/2 water or a lime-away cleanser will help loosen mineral deposits.
  6. If the evaporator pad has excessive mineral deposits, replace with a new “990-13” evaporator pad. Install trough and drain pan. Replace cover and the distributor tube to proper position over the distributor trough.
  7. Check drain line for mineral deposits, clean or replace as necessary.
  8. Connect the 1/4” water supply tube to the filter assembly and tighten. Turn on the water supply and check all points for leakage. The operation of the unit may be checked by starting the furnace blower with the manual switch on the fan control or by starting the furnace. The humidifier operates only when the furnace blower is running. Check the humidifier for proper operation.
  9. During the summer season, turn off water supply and electrical power to humidifier.

When you are finished, you should have three connections like this:

  • The black wire from cord, a black wire from board, a blue wire from board.
  • Other blue wire from board, a black wire from motor, a black wire from valve.
  • The white wire from cord, other black wire from board, other black wire from motor, other black wire from valve.

Finally, all the green wires should come together under the screw of the “L” bracket.

Tip: The most common installation mistake involves bundling of the various wires in the wire nuts.

At the factory we put a coating on the evaporator pad that helps it absorb water and control water flow. This coating is very efficient, however, it is also fragile. The coating is similar in composition to the minerals that accumulate on the pad. If you subject the pad to cleaning with an acid, you usually remove much of the coating and the pad becomes ineffective. This reduces the output of the humidifier and increases water consumption.

Instead we suggest the evaporator pad be replaced each year.

Studies by the EPA (Environmental Protection Agency) and other organizations have found that people spend as much as 90% of their time indoors. Today’s building construction practices means our homes and other buildings in which we spend time are more airtight and energy efficient than ever. As a result, we trap potentially irritating and harmful substances such as chemicals, odors, pollen, smoke, bacteria, mold spores, animal dander and numerous other irritants inside our homes. Various studies indicate poor indoor air quality has been linked to chronic diseases such as diabetes, asthma, allergies, cancer, Alzheimer’s disease, heart disease, high blood pressure, weight gain, internal organ damage and respiratory infections. Since studies of indoor air have found that air inside the home can be as much as 100 times more polluted than outdoor air, indoor air quality should be a concern for everyone. Young children and the elderly are most susceptible to poor indoor air quality.

Consider this:

  • Each person inhales over 3,500 gallons of air each day. Children inhale more particles for their size than adolescents or adults. The average person takes 20,000 breaths per day!
  • Polluted air causes 94% of all respiratory problems.
  • More than 31 million Americans have been diagnosed with asthma, about 1/3 are children under 18.
  • About 40,000 dust mites, a common household allergen, can live in one ounce of dust.
  • An estimated 10-15% of the entire population may be allergic to cat or dog dander.
  • A person sheds up to 700,000 skin flakes per day.

Indoor air pollution comes in 3 basic variations:

  • Particulates (35%): Particulates include: pet dander, dust, dust mites, asbestos dust, pesticides, pollen, post-fire ash, spray mist from aerosol products and more.
  • Gases (31%): Gases include: tobacco, paints, welding fumes, chemicals, varnishes, correction fluids, paint strippers, household cleaning products and more.
  • Germs (34%): Germs, mold, bacteria and viruses breed in consistently moist and / or unclean environments. They’re introduced into your home with water damage or when people enter your home.

There are many sources of indoor air pollution in any home. These include combustion sources such as oil, gas, kerosene, coal, wood, and tobacco products; building materials and furnishings as diverse as deteriorated, asbestos-containing insulation, wet or damp carpet, and cabinetry or furniture made of certain pressed wood products; products for household cleaning and maintenance, personal care, or hobbies; central heating and cooling systems and humidification devices; and outdoor sources such as radon, pesticides, and outdoor air pollution.

Some sources, such as building materials, furnishings, and household products like air fresheners, release pollutants more or less continuously. Other sources, related to activities carried out in the home, release pollutants intermittently. These include smoking, the use of unvented or malfunctioning stoves, furnaces, or space heaters, the use of solvents in cleaning and hobby activities, the use of paint strippers in redecorating activities, and the use of cleaning products and pesticides in housekeeping. High pollutant concentrations can remain in the air for long periods after some of these activities.

You should first consider a variety of factors when selecting the air cleaner that best suits your needs, such as:

  • Current Health (Do you or another family member have asthma? allergies? other chronic health issues, as previously mentioned? Are your eyes, throat, nose irritated? Do you often have headaches? Do you feel dizzy or tired? Have you noticed changes to your health after remodeling, renovating or moving?)
  • Environment (Is it windy? Is there a great deal of air pollution or dust in the air? Are there flowering trees nearby? Are pesticides, insecticides and fertilizers regularly used? )
  • Occupation (Do you work with chemicals? Do you work in a particularly dirty/dusty environment? Do you work near fires?)
  • Lifestyle (Does someone in the house smoke? Do you have hobbies that involve chemicals? Paint? Sanders? Welders? Do you use / store a variety of cleaning solvents in your home?)
  • Housing (Do I live in a house where I can install a whole-house system? Or do I live in an apartment and need to use a room model? Is my home well ventilated? Is it always stuffy or smelly? Do I find rodents or cockroaches often inside my home?)
  • Where you live (Example: if you live in Florida, chances are insecticides / pesticides are regularly sprayed and come into your home via your shoes. Do you live near an airport where planes fly overhead? Do you live near a plant where chemicals are used? Do you live near a highway with substantial exhaust fumes?)
  • Circumstances (Did you just install new carpet? Have you remodeled your home? Has your home suffered flood damage or other water damage? Do you have a fireplace or a gas-burning stove?)
  • Budget (What can your budget afford?)

Any of the single factors above can indicate the need for an air cleaner. If your current circumstance includes several of the above factors, you should seriously consider installing an air cleaner in your home. Whole house air cleaners are best Vs room air cleaners, as room air cleaners don’t stop contaminants in the rest of the house from circulating everywhere.

GeneralAire® HEPA and TERSus Air Cleaners are of the best in the industry. Hospitals use HEPA filters because they utilize the highest-efficiency filter with carbon to remove virtually all contaminants and particulates from indoor air (dust, pet dander, bacteria, mold spores, gasses, odors and more). TERSus air cleaners combine the efficiency of HEPA (eliminating particulates) with UV air purification (eliminates mold, bacteria, viruses and other bioaerosols). GeneralAire® also offers MAC and AC Series air cleaners and commercial air cleaners. Many air cleaners allow you to purchase replacement filters of varying efficiencies to best suit your needs. Today’s whole house air cleaners overall substantially improve the quality of the air you breath in your home.

Normally air is cleaned by an HVAC-installed air cleaner while the HVAC system is on (actively heating or cooling the house) because it moves air through the air cleaner filtration system. The air is not being actively cleaned when the HVAC system is off because air is no longer being moved by the HVAC system through the air cleaner.

In "event-based" air cleaning, you can control your air cleaner to clean the air in your home even if the HVAC system is not heating or cooling. How do you do this? By simply turning the blower fan in your HVAC system on when the heating and cooling function is off. This keeps air flowing through your air cleaner at all times, whether heating, cooling or simply running the blower fan.

Why would you want to do this? Maybe the outdoor seasonal pollen has made its way inside and is causing an increase in allergy or asthma triggers. Maybe someone in your home has a chronic health concern that requires constant air cleaning. Maybe you are remodeling and demolition particles from drywall, wood, insulation and other sources are everywhere!

Companies may advertise "Event-Based" air cleaning as if it's new, special or unique technology. The fact is ALL whole house HVAC-installed air cleaners (including GeneralAire®) are capable of event-based cleaning; either manually (by simply turning your fan on at the control unit / thermostat) or automatically (with a programmable control unit / thermostat). If you wish to use a thermostat for automatic control, be sure it is one designed to program your heating, cooling and fan operations.

Air is cleaned by an HVAC-installed air cleaner while the HVAC system is on (actively heating or cooling the house, or while the blower fan is on) because it moves air through the air cleaner filtration system. As the air passes through the air cleaner and the filter media within, it traps the unwanted particulates, allergens and contaminates. The air leaving the air cleaner after passing through the filter is free of particulates, allergens and other harmful contaminants. UV Purifiers (as found inside the TERSus Air Cleaner) utilize germicidal irradiation like the sun outdoors to eliminate mold, bacteria, germs and viruses from the air.

Not completely. There will always be some dust that settles on furniture, as is it is too heavy to stay airborne and travel through your air cleaner. To ensure your air cleaner is providing the greatest benefit, either run it continuously or run it often to keep air circulating through the air cleaner. Be sure to change your air filter media as recommended; or in the case of an electronic air cleaner, clean it per the recommended intervals. Be sure to use authentic GeneralAire® replacement filter media.

The warranty on GeneralAire® residential air cleaners range from 5 to 10 years, depending on the unit purchased

Air cleaner filters are made of a variety of materials, including fiberglass, cotton, carbon, paper and even metal.

Carbon (often found in HEPA air cleaner filters) is used because it is very safe and effective in eliminating harmful gases, molecules, chemicals, fumes and odors from the air. HEPA filters are made out of very fine glass threads with a diameter of less than 1 micron (a micron is 0.00004 in, 0.001 mm). By comparison, a human hair has a diameter of about 75 microns (0.003 in, 0.07 mm). The fine glass threads are tangled together and compressed to form a filter mat. HEPA filters will collect particles down to 0.3 microns (0.00001 in, 0.0003 mm) in diameter. Because GeneralAire® HEPA Air Filtration Systems combine HEPA filters with carbon-based materials, they stop mold spores, bacteria, viruses, pet dander and dust, and also help to eliminate harmful gasses and odors from your home. Thus, the air that leaves this type of air purifying system is cleansed and almost totally free from contaminants.

For several reasons:

  • Dirty air filters represent the #1 cause of system breakdown. A dirty air filter restricts air flow into your HVAC systems air handler, placing additional strain on the air handler fan motor. Over time it can burn out the motor, cause your system to overheat and ultimately fail. Filter replacement is essential to extending the life of one of the biggest financial investments in your home.
  • A dirty air filter consumes more energy, by making your fan motor work harder. One of the easiest and quickest ways to reduce your energy bill is to replace your air filter.
  • A dirty air filter reduces the air quality in your home, aggravating allergies and asthma (particularly in children and the elderly). Change your filter regularly to protect your family’s health.
  • A dirty air filter makes the rest of your heating and air-conditioning systems and ducts get dirty faster. This leads to costly air duct cleaning expenses or the need to replace your unit(s) sooner than you expected.

The GeneralAire® GA50 Series Air Cleaners do not require filter media replacement, but instead cleaning of the cells in inside the unit. Clean every 3 months to keep these units running smoothly.

Go to the top banner under Common Replacement Parts Source finder and check for a local wholesaler in your area

Your air filter can be located in the following places:

  1. Next to your furnace or air conditioning system air handler
  2. In a ceiling or wall-mounted air grille
  3. In your attic
  4. In more than one of the above locations

The air filter is typically located at the point where the return duct enters the air handler. Look for a 1” wide hinged or removable cover. The air filter will be inside.

Some air handlers are installed in attics. The filter is accessed by removing the grate covering the return duct. If located in your wall or ceiling, simply access the filter by opening or removing the grill cover.

Many houses have more than one HVAC system, each typically with at least one air filter. Therefore your house may have air filters located at the air handler and in the returns. Check each possible location to ensure you have located all of your air filters

The air handler is the large box containing the fan and fan motor. The air handler pulls air in from the house through the “return” duct system, and then blows the air through the heating or cooling system and back into the house through the duct system.

Most filters list the dimensions on the filter frame so that you can select the appropriate size replacement filter.

Occasionally filters are not marked. In this case you will need to measure the dimensions of your existing filter or take it with you to purchase your replacement.

If you purchased your air cleaner from GeneralAire® you should use the same filter for replacement that came with your system.

You don’t have a GeneralAire® air cleaner? We also offer filters that fit other manufacturer’s systems. Go to our home page under products…air filters… to find a replacement filter media that fits your needs.

Overall: use an air filter that offers the highest level of efficiency without damaging your HVAC system. Air filter efficiency is the measurement of how well the filter removes particulates from the air before it enters the air handler; known as a MERV rating. A MERV-rated air filter “cleans” the air by serving as a physical barrier to particles hanging in the air. A pleated air filter provides greater surface area to trap particles than a flat panel filter and will thus capture more particles.

MERV stands for Minimum Efficiency Rating Value, an industry standard rating system telling you how efficient a filter is at removing particulates from your indoor air. A MERV rating is a numerical value ranging from 1 (lowest efficiency) to 16 (highest efficiency/best). GeneralAire® air cleaners carry a MERV rating from 8 to 13, not including the HEPA AC500, which removes 99.97% of all particulates from the air

Generally the higher the MERV rating the better job it does at cleaning your indoor air. HEPA air cleaners and filters are considered the best in the market.

It depends on a couple factors. First, is your system new or old? One might think the higher the MERV rating the better. But sometimes using the most efficient filter (higher MERV rating) is not the right answer. This is because as filter efficiency increases, there is a corresponding increase in the level of air flow resistance. A highly-efficient filter may restrict air flow to a level that will damage your HVAC system by placing additional strain on the fan motor.

Second, does someone in your home suffer from allergies or asthma? Do you have small children or an elderly person living in your home. Each of these groups are more susceptible to the adverse health effects associated with poor indoor air quality, therefore, you may want to ensure you install the best in indoor air filtration.

Regardless, you should use a filter rating that best corresponds to the requirement of your HVAC system (and health concerns), and yet provides maximum air cleaning benefit. When in doubt contact your manufacturer, your installer or an HVAC maintenance company.

Absolutely. A more efficient air filter is designed to do a better job of cleaning the air as it enters your HVAC system, and ultimately into your home.

The few extra dollars spent on a high efficiency air filter actually saves you money overall! By investing in the high efficiency air filter you can ensure that your HVAC system is as clean as possible, the air in your home is effectively filtered and your system runs smoothly

Very likely. Experts have estimated that the average cost savings derived from using a high efficiency filter is approximately 10%. This cost savings includes the reduction in fuel consumed by your HVAC system, and reduced repair and maintenance costs. This does not include the cost of system replacement resulting from failure to replace your filter.

Filter replacement frequency varies by system, by the age of your system, your lifestyle (indoor smokers may choose to change their filters more often) and by the manufacturer’s warranty. Additionally, if you have pets, or if you live in a location that has more dust, pollen or similar air particles, you may need to change your filter more frequently. Are you remodeling your home? Again, you might change the air filter more often. We recommend checking your filter monthly. GeneralAire® also offers the G99 Air Filter Gauge. As the G99 fills with particles from your indoor air, air pressure changes, raising the indicator arm that tells you it’s time to change your filter.

Yes. Upgrading older HVAC units to high-efficiency units, replacing dated home insulation with today’s higher-quality home insulation, and upgrading or repairing old windows all help to make your home more efficient and green. Ventilate often. Clean often. Discourage smoking indoors. Vacuum carpet often, especially if your carpet is new. Remove shoes upon entering your home. Ensure exhaust fans in bathrooms and kitchens work efficiently. Control humidity levels, as higher humidity levels increase presence biological contaminants. Immediately clean, disinfect and dry water damaged areas. Ensure fireplace flumes work correctly. Store chemicals in your garage or a wellventilated area out of reach of pets and children. Store as few as possible. Keep pets well groomed. Empty your cat’s littler boxes daily.

  • On your control panel (via the APP or the unit's touch screen), turn your dehumidifier on by simply selecting "On".
  • Once the unit has finished sampling the air, select "Settings".
  • UNITS: Select "Units" to choose between Fahrenheit or Celsius.
  • REMOTE HUMIDISTAT: If you install a remote dehumidistat, select "D1/D2 Logic" to choose "Yes" or "No".
  • SETPOINT: To change the humidity setpoint, select "Humidity Setpoint". Press "Up" or "Down" to change to your desired setting (following screen).
  • HUMIDITY OFFSET: Select "Humidity Offset", range is +/-8.
  • FREEZSTAT LOCKOUT OFF AND ON SETPOINT: Your control allows you to adjustable the freeze stat temperature cut-off (28°-34°F / -2°- +1°C) and turn-on (48°-52°F / 9°-11°C). The adjustability of the freeze stat allows the dehumidifier to run efficiently in low temperature conditions.
    • Set OFF with ranges from 28°F to 34°F / -2°C to +1°C; and ON with ranges from 48°F to 52°F / 9°C to 11°C.
  • DEWPOINT LOCKOUT SETPOINT: Adjustable from 36-42°F.
    In addition to the low ambient temperature 50°F (incoming air) on the previous version of firmware, the added low dew point temperature lockout will further ensure the dehumidifier runs more efficiently.
    • Simply select "Dewpoint Lockout Setpoint" to set; with range from 36°F / 2°C to 42°F / 6°C.
  • FAN IDLE: In low outdoor temperature settings, this can help make the dehumidifier run more efficiently by turning the drain cycle feature off.


Download the GeneralAire Wi-Fi APP to your smart device from either your APP Store or Google Play.

Click here for a step-by-step guide on solving connectivity issues.

The good news is that the APP has been updated so that if it becomes disconnected, the APP will continue trying to reconnect until it is restored.

  1. Go to your control panel, select "Settings".
  2. On the next screen, select "WiFi".
  3. On the next screen, select "Scan"
  4. Select the service you wish to use, ensuring it is a 2.4 GHz connection.
  5. Enter the Wi-Fi password. (Passwords are case sensitive.)
  6. On your smart device, open the GaneralAire Wi-Fi APP.
  7. Enter the dehumidifier's 6-digit PIN, found in "Settings", "Mobile App Pin".

Click Here to view a video demonstration.

WARNING: Shut off the unit and unplug the dehumidifier power cord before performing this activity.

  1. Using a Phillips-head screwdriver, locate and unscrew the screw at the top of the filter door (nearest the control panel) by a quarter turn. Remove the door and the filter.
  2. Using the T15 Torx wrench (included with the unit), locate and unscrew the four screws holding the display board in place.
  3. Once the board is loose, unplug the two wire inserts. Set aside the old display board.
  4. Insert the new display board through the open filter door, and place behind the display board opening, ensuring the arrows are pointing up.
  5. Reconnect the two wire plugs to the new board.
  6. Using the Torx wrench, screw the four screws back into the new board, holding the back of the board until all four screws are fully seated.
  7. Replace the filter and the door.

For these instructions with photos, click here.

  1. On your control panel, go to settings.
  2. Select "Fan".
  3. Select "Cycling".
  4. Select the amount of time, per hour, you would like the fan to run: 10, 20, or 30 minutes.

Yes. You must replace the MERV 11 pleated filter a minimum of once a year to ensure your unit is running smoothly. Depending on environmental conditions, you may need to replace it more often. Do not run your dehumidifier without a filter in place.

Because the air coming from the dehumidifier is slightly warmer than the room temperature, there can be a slight warming effect in the basement. This will further assist in lowering the Rh of the basement, as the same air at higher temperatures has a lower Rh. Click Here to learn more.

Warm air is brought into the unit and is passed over refrigerated coils, causing condensation that goes down the drain and gradually decreasing airborne moisture. Once the humidity set point is reached, the dehumidifier shuts off.

Any region with a summer dew point average above 55° needs dehumidification, separate from cooling. While one would typically think the Southern states would most often fit this circumstance, this would even include cities such as Chicago, Detroit, St. Louis, and more, as all have dehumidification needs.

The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) recommends keeping the relative humidity in a home between 40-60%. Outside that range your risk of being adversely affected increases. In addition, the Journal of Allergy and Clinical Immunology recommends keeping indoor relative humidity below 51% in order to deter dust mites and boost overall comfort of the home.

DH100: Up to 100 pints per day
DH75: Up to 75 pints per day
DH70: Up to 70 pints per day
DH95: Up to 95 pints per day

The DH75 & DH100 have been specially designed for small spaces such as basements, crawl spaces, closets, garages, and attics of homes, condos or apartments. Each come with adjustable feet that allow for level installations even if the floor is not level. You can even suspended them from the ceiling (with optional accessories).

Our dehumidifiers offer 5-Year Warranty.

First, let's learn a little about dust mites.

  • Genus: Dermatophagoides; Mites are Arachnids (members of the spider family).
  • Species: Dermatophagoides Farinae (DF) - commonly found in North America.
  • Size: About 250 to 300 microns (µm) in length.
  • Adult Mite Lifespan: Up to 3 months; (3 larval stages).
  • Reproduction: Female mites lay about 25 to 50 eggs.
  • Habitat: Mites live in carpet, fabric upholstery, and mattresses.
  • Diet: Human skin scale, animal dander and trace nutrients. Mites need to absorb humidity, they cannot drink water.
  • Allergen: Dust mite fecal material.
  • Body Color: Translucent.
  • Average Threshold before Developing Allergies: 100 mites/gm of dust.
  • Allergic Reactions: asthma, rhinitis.
  • Living Conditions: Temp. Range: approx. 59°F to 95° F (15°C to 35°C).
  • Relative Humidity Range: approx. 55% to 85%.
  • Number of People in the US Suffering from Allergies: 50 million and rising.

Dust mites are the most common allergen-producing organism found in homes. They live in carpets, upholstered furniture, bed pillows and mattresses. If the relative humidity in your home is below 50%, dust mites desiccate. If the relative humidity rises above 50% they strive and reproduce, their appetite increases, and therefore their fecal matter (the source of the dominant dust mite allergen) increases. Ninety percent of the population that experiences any allergy-based symptoms reacts to dust mite allergen.

Vacuum often. Washing bedding in hot water has been shown to reduce dust mites. Since stuffed toys are a breeding ground for dust mites, choose toys that can be washed and thoroughly dried, and keep them off beds to reduce the exposure received during long hours of sleep. It may also help to put stuffed toys in the freezer for a day or so.

The best solution is to control the relative humidity in your home. Dust mites can not survive in areas where the humidity level is below 50%. Have the relative humidity checked in your home during summer and fall. Relative humidity can be controlled by the use of a whole-house dehumidifier installed adjacent to the air conditioner. By controlling the humidity, you completely remedy the dust mite problem.

Our dehumidifiers are not designed to work in pool applications due to the corrosive nature of chemicals that are used in swimming pools; chemicals that can become airborne and corrode components within. You may contact Desert-Aire at (262) 946-7400, as they may have models designed for pool installation.

You may purchase your replacement filter through your local contractor or from our website. Click here to shop online.

There could be a few reasons for this:

  1. Do you have the drain trap installed correctly? An upside down trap will cause leakage.
  2. Ensure a drain vent is installed with the drain trap.
  3. Are the PVC connections snug?

WARNING: Unplug the unit from its power source before performing any maintenance. If the power cord is difficult to reach, shut off the power breaker that provides power to the dehumidifier.

DH75 & DH100

  1. Using a Phillips-head screwdriver, locate and unscrew the screw at the top of the filter door (nearest the control panel) by a quarter turn. Remove the door and the filter.
  2. Simply slide the new MERV 11 filter in, with the air flow indicator arrows pointing towards the unit.
  3. When your dehumidifier is new, you will want to check the filter every month. Depending on the environmental conditions, your filter may require more frequent replacement.

Click Here to watch a maintenance video demonstration. (You will be taken to a partner site.)

DH70 & DH95

Click Here to watch a video demonstration on changing the filter in your DH70 or DH100 dehunmidifier. (You will be taken to a partner site.)

Click here to complete our new product warranty registration online.

No. The MERV 11 filter is essential to provide protection of the internal components. Running a dehumidifier without a filter voids the warranty.

If you are a home owner, we recommend you purchase through a qualified contractor to install your dehumidifier professionally.

Click here to find a contractor. If one is not listed for your zip code, click here to find a wholesaler that may be able to recommend one for you.


We do not endorse any individual contractor, but you may search for a local contractor by clicking here, or contact a local wholesaler to request a referral by clicking here. You might also inquire through your neighborhood network for a referral.

Click here to shop online, or contact a local contractor or wholesaler for replacement parts. All maintenance and repair should be conducted by a qualified contractor.

Please refer to your wiring diagram, denoting the use of the D1, D2 connections.

Yes. Please refer to the wiring instructions that accompany your Nest controller.

  1. Check the filter and change if dirty.
  2. Check possible airflow blockage.
  3. If neither of the above fix the issue, call Technical Support (866) 476-5101

UV (Ultraviolet) Air Purifiers utilize ultraviolet light to kill mold and mildew, as well as eradicate VOC's, airborne pathogens, flu, germs, bacteria, viruses, and other harmful airborne contaminants. Some models also remove odors from the home caused by garbage, hobbies, cooking, etc. UV Air Purifiers are an effective option for people with respiratory problems as they greatly reduce allergy and asthma triggers. In fact, studies have shown that UV lights reduce fungal contamination within air-handling units.

Both products are effective at removing harmful elements from the air, but UV Air Purifiers focus on removing airborne germs, bacteria and mold while filtration focuses on removing harmful particulates that become airborne.

Your UV Air Purifier requires little maintenance. Simply replace the bulb once per year, or once every two years depending on the model.

The CDC currently recommends UV lights to reduce transmission of tuberculosis in hospitals. Together the National Institute for Occupational Safety & Health (NIOSH), the Department of Health & Human Services (DHHS) and the CDC wrote a manual for effective UV light installation; recommending UVGI (Ultra Violet Germicidal Irradiation) light technology to kill or inactivate airborne TB bacteria.

Read Their Manual

EPA: According to two studies, operating UV lamps installed in HVAC systems to irradiate the surfaces of air-handling units does not result in increased concentrations of ozone.

Read What They Say


UV light can be harmful just as the sun's UV light can be when someone is exposed for too long a time. One should neither look at or touch a UV light bulb while it is on for any length of time. Fortunately, when the UV light system is installed in your HVAC system, there is no direct or harmful exposure to you or your family. Remember to power off your purifier before replacing the lamps and do not look directly at a lamp that is powered on.

Photocatalytic Oxidation is an effective way to neutralize many types of airborne bacteria, chemical contaminates and odors. Photocatalytic oxidation is achieved when you combine UV rays with a TiO2-coated filter. TiO2 refers to Titanium Oxide. This process creates hydroxyl radicals and super-oxide ions, which are highly reactive electrons. Titanium dioxide, TiO2, is a well-known metal oxide with photocatalytic properties; it has been incorporated into non-woven filtration fabrics to aid in degradation of volatile organic compounds (Park et al., 2006). In this system, the metal oxides act as a photocatalyst in the presence of UV light.

Once bound together, the chemical reaction takes place between the super-charged ion and the pollutant, effectively "oxidizing" (or burning) the pollutant. This breaks the pollutant down into harmless carbon dioxide and water molecules, purifying the air.

·In a study commissioned by the U.S. Department of Energy, scientists found that photocatalytic oxidation converted more than 95% of harmful VOC chemicals to harmless carbon dioxide and water molecules.



UV lights significantly reduce the amount of microbials in ductwork and other airspace in your home. UV lights have the ability to kill viruses, germs and bacteria throughout the home. The 1903 Nobel Prize for Medicine was awarded to Niels Finsen for his use of UV against lupus vulgaris, tuberculosis of the skin. Using UV lights to treat water dates back to 1916 in the USA. Today UV light is used to treat drinking water, waste water and indoor air.