How to Replace an HVAC Filter in 5 Easy Steps

Posted on Aug 15, 2019

Owning a home comes with its own set of responsibilities. You are responsible for upkeep and maintenance, like mowing the lawn and cleaning on a regular basis. But one task that most homeowners neglect is HVAC filter replacement.

For Replaceable HVAC Filters

If your home has a reusable filter, then this post doesn’t apply to you. However, if your home uses replaceable filters, then keep reading below!

Changing the filter in your HVAC system is something you should be doing every couple of months. Doing so helps the air in your home stays clean and fresh, without allergens like dust and mold.

Don’t worry – this is a very easy task to do. Below, we’ll dive into the simple process of HVAC filter replacement and you’ll be back to enjoying homeownership in no time!

Determine the Right HVAC Filter Size

Residential HVAC systems are fairly easy to maintain. First, you need to determine the correct size of the air filter. To do this, look at the side of your system and look for dimensions. Some common examples include 10×20 or 14×20. This will tell you the size you need to buy at the store.

Next stop, head to your local hardware store. You’ll find tons of filter options for your HVAC system, but don’t get overwhelmed. Make sure you’re getting the correct size because any other size will not fit in your system.


You may want to also pay attention to the MERV number. The MERV number will tell you what size particles the filter is capable of grabbing from the air passing through it. The higher the number, the smaller the particles.

For example, medical facilities and hospitals use MERV 16 or higher because they do a great job of industrial cleaning by removing high levels of particles from the air.

Just keep in mind that the higher the number, the more the air filter will trap inside of it. This may require more frequent replacement depending on your home.

Turn Off the HVAC System

When you have purchased the new air filter for your HVAC system, head on home to do the replacement.

To start, you need to turn off the system. Just switch your thermostat to the “off” position for the duration of the replacement, to ensure that it doesn’t kick on while you’re changing the air filter out. The last thing you want is dirt to go flying everywhere!

air filter

Replace the HVAC Filter

Next, it’s time to replace the filter. This step is a lot easier than it sounds, but we’re going to break it down for you so you don’t miss anything. 

Remove the Old HVAC Filter

Begin by removing panel door. This can be found on the side or bottom of the system and looks like a little cover. Gently remove it and set it aside.

Then take out the old air filter. Don’t be alarmed if it’s really dirty – this means that it has been doing its job! Carefully throw it in the trash without disrupting it too much. You definitely don’t want the dirt and allergens to get thrown back into the air.

Insert the New HVAC filter

With the old filter removed, you can then insert the new filter. This sounds pretty straightforward, but there’s one thing to note: there is a right and a wrong way to insert a new filter.

Look for the arrows on the side of the filter. This will tell you which direction to slide it into your HVAC system. Doing this step incorrectly will result in the air filter not capturing dust and allergens like it should. They are designed for air flow from one side to the other, so make sure that it is being inserted correctly.

Secure the Panel

When you’re done, then re-secure the panel onto your HVAC system. Clean up any dust or particles that fell on the floor around you and make sure that the space is clear of any wrapping from the filter.

Turn the HVAC System Back On

Now, head back to your thermostat and turn it back on. You may want to have it run for a few minutes, just to make sure that everything sounds normal. That’s entirely up to you, though. 

And there you have it! 5 easy steps to replacing your home’s air filter. It’s pretty simple, huh? No need to stress about it, just make sure that it is on your to-do list every couple of months so your air can continue to smell clean and fresh (and allergy-free!) 

Ask for Assistance

Are you uncomfortable with doing your own HVAC filter replacement, or perhaps you’re still not sure how to do it? No problem!

Trust Your Local HVAC Service Professionals

AIRPRO Indoor Air Solutions has been serving the residents of Hawaii for over 20 years, providing exceptional commercial and residential HVAC service for homes and businesses. We would be more than happy to help you with any issues you may be experiencing. 

Give us a call today, we’d love to walk you through the process of air filter replacement!