Humidifier Settings, Installation and Maintenance Tips

During extremely cold weather, your home loses humidity to the outdoors and may drop to as low as 10%. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommend that your home maintain a humidity level between 30-60%. As the exterior air temperature changes so do the optimal interior humidity levels of your home (see chart below):

A simple visual inspection test, look at the condensation forming on your windows. If excessive moisture collects on windows your humidistat is set to high. Excess humidity over a prolonged time can damage windows and walls especially when outdoor air temperatures are very low. As the temperature drops outside so must the humidity levels in your home. If the weatherman calls for a prolonged cold snap be sure to lower your humidistat.


In general, we recommend setting the dial at 35%. You may want to raise or lower it slightly because each home is different. Increase the humidity setting until you see a small accumulation of water droplets forming on the bottom half inch of your window panes then back it off slightly (a few percents) to ensure the proper humidity level for your home have been reached.

Depending on the model you choose and the size of your home, a humidifier uses from 1 to 15 gallons per day when the furnace is operating. This minimal amount of water is enough to raise the humidity to your desired level


A whole house humidifier is installed in the ductwork, right beside your furnace. Although it can be installed by a handy do it yourself homeowner it requires knowledge of HVAC, plumbing and electrical so it may be outside the expertise level for the average do it yourself homeowner (Tip: leverage ServiceLive to find a professional in your area).

As far as console/room humidifiers, simply purchase one at your favorite retailer, following the instructions and plug it in.


One of the most important aspects of a humidifier, whether it’s a console/room unit or a whole-house unit, is the filter. The filter allows air to circulate through the wetted media trapping particles and adding clean water to moisten the air. Depending on your water’s hardness and mineral content you may need to change your filter twice during the season (Tip: if you have the humidistat on max and the air in your home is still dry and/or your console/room humidifier doesn’t need refilling as often, it’s probably time to replace the filter).

Whole-house humidifiers are recommended for their lower maintenance and because they evenly distribute the humidity across the entire home. Because of lower water requirements, a whole house humidifier can run for eight to twelve weeks before needing a thorough cleaning (Tip: do it your self by purchasing a filter sold at major home improvement big box stores and/or local hardware stores. Simply right down the make/model, purchase and replace the filter… the process is similar to changing your furnace filter).

Console/room humidifiers, on the other hand, need to be refilled daily and may need to be cleaned out weekly during the season to remove any mold and bacteria build up.

Regardless of the type of unit you have we recommend installing a new filter at the start of the season and then once again after the first of the year (every 2-3 months depending on the hardness of water in your area).

9 Responses

  1. Barry Crouch says:

    It is also important to know which type of humidifier is best for you – a warm or cool mist humidifier. There are only a couple of difference between the warm and cool mist humidifiers. For example, if small children are in the house the cool mist is recommended. However, it is important to consult your physician to determine which is better for you and your family.

  2. Chet says:

    Thanks for this — it reminded me I need to change my filter! The 35% threshold is a useful tip also.

  3. Jim says:

    Remember on super cold days to turn your humidifier down. If you can see condensation/water forming on the inside of your windows (usually starts on the bottom edge) then your humidifier is set to high. I typically run mine around 30 percent and when the outside temp drops below 20 I drop my humidifier setting to 25… if the outside temp goes below 10 then I drop the humidifier setting to 20. It is also a good idea to replace the filter twice per season as many areas have hard water and the filter gets coated with calcium and lime.

  4. Adi says:

    If there’s a baby in the house, making sure the house has the right level of humidity is very important!
    (Having a 3 month old, I take extra care with this).
    Thanks for this post!

  5. Frank Jovine says:

    Glad this post was helpful. Jim I had that condensation problem at my old house. What a pain.

  6. Fred says:

    For a cold weather, steam from boiling pot is great and save. But don’t recommend if you have a child in that room.

  7. Saz says:

    This is a really helpful article. Thanks.

  8. Nancy says:

    this is a very good thing, indeed, indispensable in any home, but it requires constant care, sometimes it does not reach the hands. are there ways to make the care of the humidifier less often?

  9. Mike says:


    I have a home furnace / humidifier installed and recently the temperature have been dropping to -20C. Before this big temperature drop, the humidity was around 40%. Since the drop, the home humidity is now around 25%.

    I have not changed the humidity level and the filter was installed in Oct. Of last year.

    What should I do? Is something wrong with my humidifier? I didn’t understand why the article says to dial down humidity as temperature drops…even though there’s even less humidity in the house.

    Appreciate your response. Thank you!

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