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The Basics of Changing Your Furnace’s Humidifier Filters

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In any home, the right temperature matters because it helps make the environment comfortable. Using an air conditioner is relatively straightforward for cooling, but using a furnace for heating is often tricky because it’s difficult to gauge how much heat is needed to warm the home. However, furnace performance can help with this, especially since it’s easy to spot issues in one.

A few things can cause a furnace to underperform, and they usually have to do with the furnace itself or the ductwork. However, some parts do more work than the others, such as the humidifier filters. These filters are responsible for removing impurities from the air, so keeping them clean and in working condition is essential. However, few homeowners know how to change them, much less when to do the task. For this reason, we’ll discuss the details in this article.

How a Furnace Works

A furnace is a mechanical device that uses a heat source to warm the air in the home. The heat source is usually a gas, electricity, or oil, and it’s contained in a combustion chamber. The heat is then transferred to the air through a heat exchanger that is usually made of metal.

The air is then forced through the ductwork into the house’s rooms. As the air enters the furnace, it passes through a filter that catches any impurities in the air. The air is then forced through the heat exchanger, which transfers heat to the air through the ductwork into the house’s rooms.

The Role of the Humidifier Filter

The furnace’s humidifier filter is located in the humidifier, a device that adds moisture to the air. The humidifier filter is responsible for removing impurities from the water used to moisten the air. Aside from catching particles, the humidifier filter also prevents the growth of bacteria and mould in the humidifier.

Many things can cause the humidifier filter to wear down, such as exposure to dust, chemicals, water, and excessive heat. The last one is particularly troublesome because it can cause the filter to warp. A warped humidifier filter can cause the furnace to work harder and use more energy, leading to higher utility bills.

The Role of the Evaporator Pad

The evaporator pad is also located in the humidifier and is responsible for absorbing the water to moisten the air. It is usually made of foam material, and its typical lifespan is about one year. The evaporator pad can also become warped over time, making it difficult for water to absorb.

As a result, water can leak from the humidifier, causing damage to the furnace and potentially leading to mould growth. Warped evaporator pads can also cause the furnace to work harder and use more energy, leading to higher utility bills.

When to Change Your Furnace’s Humidifier Filter

For any furnace, changing its humidifier filter should be done at least once a year. This is because the filter can become clogged with dust and other particles, making it difficult for the humidifier to function correctly.

If you have pets or live in a dusty area, you may need to change the filter more often. In this case, you may need to change the humidifier filter every three months.

How to Change the Humidifier Filter

To change your furnace’s humidifier filter, you’ll need to turn off the furnace. You must also disconnect the water tube and replace the humidifier filter or evaporator pad with new ones.

Once done, replace the filter or evaporator pad, reattach the water tube, and then the cover. Finally, turn the furnace on to see if the new filter or evaporator pad is working correctly.


A furnace’s humidifier filter is crucial because it improves your home’s air quality by reducing the amount of dust and other allergens in the air. Since a furnace’s humidifier filter is constantly working to improve the air quality in your home, you must change it regularly to ensure it works properly. All that matters is doing it correctly to prevent further problems.

Climate Experts provides top-quality services for furnace repair in Pickering. Our professional heating and cooling technicians will ensure your home is adequately ventilated, all for fair prices. Visit our website today to request a free estimate!

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