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Whole House Humidifier and Mold??

x_navyfc | Posted in Energy, Heating & Insulation on February 14, 2021 08:56am

I need to install a whole house humidifier to get my home’s humidity up to a safe level for hardwood flooring.

I heard people saying that these are a culprit for mold growth inside ductwork.

I would most likely buy an Aprilaire 700 motor operated evaporative humidifer and run it from my smart thermostat to adjust humidity output based on outside temperature.

Would a set up like that normally cause mold growth in ductwork?

I’m guessing that running a humidifier without lower the humidity setting when temperatures fall would be the reason for mold growth.

Is there anything else that would help lower the possibility of mold growth in the ductwork if I installed the humidifier?

Thanks.

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Replies

  1. alexshumalov1986 | Feb 25, 2021 10:09am | #1

    Aprilaire 700 with a smart thermostat (always with a humidity level checker - hygrometer) is a great decision!

    Because mold can spread quickly indoors if you have any of the following problems:

    overuse of a humidifier;
    drying clothes indoors;
    active use of a double boiler without organizing a hood;
    leakage of plumbing in the bathroom and in the kitchen;
    excess moisture in the basement if you live on the ground floor.

    The good news is that by quickly addressing the causes of high humidity indoors, you can get rid of mold, which will drastically reduce the concentration of spores in it to a level that is safe for health. To prevent problems caused by a fungus, it is necessary to get rid of both the mold itself and the excess moisture in a room, and the factors that cause it.
    Finally, you can combine humidifying functions with cooling ones by purchasing an evaporative cooler. https://evapolar.com/blog/best-portable-air-cooler/

  2. suburbanguy | Feb 25, 2021 10:43pm | #2

    I live in Ontario, Canada, and I've never heard of anyone being able to get their humidity so high that they develop a mould problem. Don't turn it on before the outside temp is continuously below freezing and turn it off when it starts warming up during the day. If you have any concerns, buy an hygrometer and you'll get a feel for it soon enough.
    There are many humidifiers that mount on the furnace ducts, but all of them that I've seen are garbage. I got sick of leaking saddle valves, floats that don't shut the water off properly and cause floor puddles, cleaning the immense amount of lime deposits each spring, etc.
    I bought a large rectangular plastic bin. I made a top for it out of MDF. I cut two holes for flexible ducting to connect to the air supply and return ducts, and use the existing shut-off damper from the drum humidifier on the furnace. I can shut off the water when I go away for the winter, while still humidifying the house. When the house is set to 53 degrees, there will still be water in the bin after 3 months. With the water shut off, no one needs the inspect our home every 3 days--with our insurance company. (I also put a thermostatically controlled heater line on the water supply line coming out of the basement floor. Alternatively, I could shut off the water at the main with the valve in the front yard. I also monitor the temp of the house and our freezer remotely with a Raspberry Pi computer.)

    Being unable to travel this winter I fill it about once a month. The lime deposits are not as thick because of the increased surface area of the bin. In the spring, shut the damper, add vinegar or H2SO4 to the water and the mineral deposits clean up easily. Remember, always add the acid to the water!!! not vice versa. High school chemistry.

    Best humidifier I've ever had.

  3. Jewenyann | Oct 10, 2023 08:39am | #3

    Running the humidifier with a smart thermostat that adjusts humidity based on outside temperature is a smart move. To further minimize the risk of mold growth, you might want to ensure proper maintenance and regular cleaning of both the humidifier and your ductwork. Also, keeping an eye on your home's overall humidity levels and ensuring they don't get too high can help.

    For more insights on maintaining healthy indoor air quality and dealing with potential issues like odors, you can check out this link https://www.damagecontrol-911.com/guide-to-removing-odors-with-ozone-generators/. It might provide you with some useful information.

  4. Achilles | Oct 17, 2023 10:42pm | #4

    Adding a whole-house humidifier to maintain proper indoor humidity levels for hardwood flooring is a good idea, but it's essential to take precautions to prevent mold growth inside your ductwork. Here are some considerations and tips to lower the risk of mold growth like Regular Maintenance, Control Humidity Levels

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