How to Replace Air Filters in Your Home: A Step-By-Step Guide

How to Replace Air Filters in Your Home: A Step-By-Step Guide
  • Opening Intro -

    Of the different systems that function inside your home, your HVAC plays some of the most crucial roles.

    It keeps your family comfortable during the summer. It also keeps you warm during winter.


Hence, Americans spend billions annually on HVAC.

But more than regulating indoor temperature, your HVAC system also keeps the indoor air quality in check. It does so through the air filters. They filter the dust and other particles in the air and prevent your HVAC from clogging.

But when was the last time you checked your air filters? Do you know how to replace air filters the right way?

Continue reading below for a step-by-step guide on how to replace dirty or old home air filters.

1. Find Its Location

There are different reasons to replace air filters. Sometimes, they incur damages due to age. Others become so dirty that they merit a complete replacement. Regardless of the reason, you can replace your damaged or dirty air filters without any professional assistance.

The first step is to find out where the air filter is. This depends if you’re replacing a filter from your air conditioning unit or a furnace.

Start by turning off your HVAC. You want to stop the movement of air during the replacement process. The best way to find the filter is to check the manual. Sometimes, it can be under the grille on the HVAC’s wall.

In furnaces, it can be on the blower compartment. Another possible location is inside the metal ductwork. You will find this right before you reach the blower fan.

2. Determine the Size

After locating the filter, your next step is to determine its size. This is crucial to avoid purchasing a replacement with the wrong size. In this case, your manual is again, your best friend.

But if you lost your manual, remove the existing filter. Go over the filter and search for the dimensions, which you can find on the cardboard frame.

If you still cannot find the dimensions, get a ruler or measuring tape. Measure the dimensions manually, covering the width, the height, and the thickness of the filter.

Write down the dimension on a piece of paper and bring it with you to the store for reference.

3. Remove the Old Filter

With a new filter on hand, you can now remove the old one. But before you do that, look for the air-flow direction arrow on the filter frame. The arrow tells you the correct direction of the airflow.

This is crucial since you want to install the new filter the same way as the old. To avoid forgetting the direction, get a permanent marker, and draw the direction of the arrow on the ductwork or furnace housing.

Thereafter, you can start removing the screws. These screws hold the filter or the lid. Make sure to place all the screws in a safe area. Next, slowly pull out the old filter.

You want to have a garbage bag beside you where you can transfer the dirty filter directly after removal. This will keep the dust from scattering all over the place.

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If the filter comes with a cover, make sure to clean it thoroughly. You can use a vacuum to clean the cover or you can also wash it. Moreover, make sure that every slot and crevice does not have any debris that may be stuck.

4. Insert the New Filter

Now you are ready to insert the new filter. Before inserting, check the arrows that you wrote earlier with a marker. Your goal is to follow the direction of the arrows as you insert the replacement filter.

Slowly insert the new filter and secure it in place by returning the screws. Also, check the filter if there is a space where you can write down the date of installation. This will serve as a guide in the future if it is time to get a new one.

The Need to Replace Air Filters

Replacing dirty air filters goes beyond the issue of efficiency. As we mentioned earlier, the chief role of air filters is to keep dust and other harmful contaminants from circulating in the air.

These elements can cause different kinds of health issues. These include coughing, sneezing, and allergies. Moreover, they can lead to more serious concerns like hives, rashes, asthma attacks, and low blood pressure.

Medical studies reveal that over 50 million Americans experience allergies every year. Furthermore, Americans spend over $18 billion annually in allergy-related expenses.

Thus, the importance of functioning air filters in your HVAC is non-negotiable.

When to Replace Your Air Filters?

How often should you replace your air filter? Ideally, you should check your air filter every month. Your goal is to look for signs that point to a replacement.

Pull out the filter and see if there’s an accumulation of pet hair or thick amounts of dust. Check if there’s a weird coloration or if there’s mold formation. If you see these signs, it is time to replace your filter.

Another thing to look out for is the performance of your HVAC system. If you notice that it is not as efficient as before, check the condition of your filter. Replace the filter and see if there’s any difference.

Air Filter Maintenance

Aside from replacing your air filter, you also need to learn proper care and maintenance. The area where you live is crucial in extending the life of your air filter.

If your house is near a gravel or dirt road, you may have to replace your air filter often. The same thing goes if there’s construction nearby.

other valuable tips:

If your place is humid, expect to see less dirt on your filter. However, humidity may cause molds and mildew to form on your air filter. Furthermore, you need to check your return air filter grille if it is still in good condition.

Go Beyond Your HVAC System

Learning how to replace air filters is a skill every homeowner should have. With your health and comfort at stake, you want your HVAC system to work as efficiently as possible. But a safe and efficient home is more than having a good HVAC system.

We invite you to check our other blog posts where we discuss home improvement topics. Discover more tips and tricks to make your house a home!

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