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  • Writer's pictureAdam Clark

Why HVAC Humidifiers Are No Good Contribute To Mold Growth In HVAC Ducts

When it comes to keeping your home comfortable, nothing can beat natural venting. However, the way our homes are built today, adding vents in many cases is not as simple as it used to be. There are so many different types of homes and apartments these days that a standard venting method no longer works for everyone. That’s where humidifiers come in! We’ve all known them by their bad names: they suck up moisture from the air and store it in a condensed form that can build up over time and cause mold to grow in the duct work beneath our floors or walls. But what we often don’t know is how much damage they’re doing even though we know they’re there! In this article, you will learn why hydrants cause moisture problems and how adding moisture to your HVAC system can increase mold growth. You may think that adding water to your HVAC system means you will get more humidity, but this isn’t always the case. You see, most humidifiers do not add moisture directly into the air as a traditional hot-air humidifier does. They instead trick your HVAC system into thinking there is more moisture in the air by circulating hot water around within a closed container called a humidifier tank. When the heat rises from the bottom of the container, it triggers an oscillating fan attached to your HVAC system that blows warm air into your ductwork .

Why HVAC Humidifiers Are No Good. Contribute To Mold Growth In HVAC Ducts

Why is adding moisture to your HVAC system dangerous?

Moisture is one of the most common problems in HVAC systems. It seeps from the walls, floors, and ceilings of homes through openings such as doors and windows. Moisture build-up can cause mildew growth and health hazards, including increased risk of cancer, allergies, and poor air quality. As stated above, when moisture levels in your home get too high, your HVAC system is meant to release moisture back into the air through your indoor air pollution sensors. Unfortunately, while a humidifier can help with moderate levels of moisture intrusion, it can also cause major moisture intrusion in more advanced humidification systems that can be used to deal with mold.

How humidifiers work

Hydrants work by shooting water into the air to create a mist that triggers air pollution sensors. They are most commonly used in commercial and residential HVAC systems. However, they can also be used as indoor garden sprinklers. Gerbers are filled with tiny reservoirs of water that are connected to each other by tubing and topped with a valve that regulates the flow of water. Practicing hydrants at home can help you identify potential problems in your own system. When hydrants are present in your home, you will often find that the air smells musty and that there is a build-up of fog in the air conditioner and heating/cooling equipment.

What causes moisture in the first place?

Here are a few things that can cause moisture in the first place: Heavy rainfall, flooding, melting snow, ice, dew, mist, condensation, and humidity. Heavy rainfall is the leading cause of moisture intrusion in the United States; however, flooding is also very common. When rainfall exceeds a certain level, the ground acts as a water reservoir, causing water to build up in the soil and eventually reach the surface. When the rain stops, the soil is still saturated and the water can easily seep through the ground and into nearby living spaces. Additionally, if flooding occurs in a neighborhood with a lot of water runoff from streets, the runoff water will overflow several times before finally reaching the ground as flooding. This is why it is important to keep the water flow on your street gutters moderate; otherwise, you will be drawing water from a very high source and causing flooding.

How humidifiers trap moisture inside their tanks

Unlike a traditional hot-air humidifier, a humidifier tank does not create air pollution. Instead, it trickles warm water down through a series of tubes and then dispels it through a fan. This fan moves the warm, moist air around within the closed tank. When the tank is not in use, you can simply empty it and store it in a safe location. If you need to humidify your air again quickly, simply turn on the heater and air conditioner and you will be breathing in dry air.

The danger of mold growth in humidified air

In a normal home environment, moisture intrusion into the air structure is not a huge issue. However, when moisture levels get too high, the walls and ceilings of your home can build up over time. This can cause mildew to grow in the walls and ceilings that are not connected to your HVAC system. When mold grows in your home, it may look like mildewed wallpaper; however, when light is optically exposed to UV rays, it will turn black and give off a moldy odor.


HVAC humidifiers are a dangerous waste of money. They are meant to keep your house at a comfortable temperature, but they have the potential to cause major problems in the event of a moisture intrusion. If you have a humidifier in your home, it is recommended that you replace it every year or two. You can find the best humidifier reviews online, as well as in our list of the best.

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