How to Change Your HVAC Filter By Yourself

It seems like something that’s always nagging in the back of our mind: change your air filter, change your air filter. We know we’ve been told to do it, but is it really that important? And if it is so important, how on earth do we go about getting it done? It seems like a lot of work for something that seems so trivial.

But it’s not trivial. There are a whole host of reasons for you to change your air filter, not the least of which are your health and your wallet. Here we’re going to look at how exactly to change an air filter, and why you should do it in the first place.

Why Should You Change Your Air Filter?

There are a whole host of reasons to change your air filter, but let’s start with the most expensive: not changing your air filter could very literally require you to buy an entirely new air conditioner unit. By not changing the air filter, condensation can build up inside the coils, freezing them over, and it doesn’t take much of that to ruin an AC unit completely. And, as we all know, air conditioners aren’t cheap.

But what about less expensive problems? If you don’t change your air filter your air conditioner is not going to run properly, and it’ll cause your utility bills to go through the roof. According to the Department of Energy, a dirty air filter can cause your air conditioner to use 15% more electricity. So that’s another reason that hits you in the pocketbook.

And what about your health? A poor air filter can lead to all sorts of allergens getting into your home which are bad enough for a healthy person, but worse if you have someone in your home with asthma or other lung diseases. And when condensation forms inside the filter–and in the duct work–you can get mold living in there, and that’s deadly serious to anyone, healthy or not. 

Where to Find the Air Filter

Before you try to find the air filter, make sure that the furnace is turned off, and if the air conditioner has been running, wait until it stops before changing the AC filter.

The air conditioner filter is located near the furnace, and it can be above or below depending on the type you have. There will likely be a narrow door that opens to allow you to access the air filter. 

An air filter looks like a thick corrugated piece of material inside a cardboard or plastic frame. It may be pleated or it may be honeycombed, but you’ll know it when you see it.

How to Remove the Air Filter

Once you’ve located the filter, pull it out of its place carefully, using both hands. (Using one hand may cause it to get stuck as it’s not pulled out straight.) The filter may feel tight, but will come loose with a little tug, and will slide out of its door. 

Now you can inspect the filter. It may look completely clean, in which case it’s possible to continue using it again (because odds are it has been replaced in the last three to four months). But if there’s dirt and dust accumulated inside it, or if the color of the filter has changed, then you’ll know it’s time for a new one.

Use the Right New Air Filter

Air filters are not one-size-fits-all. If you’re not sure what size of air filter you need to buy to replace yours, then it should say a number and designation on the side of the filter. Write that down and take it with you to the hardware store (while leaving the old filter inside the air conditioner–you don’t want to leave the AC unit with no filter, even if it’s old.) You can also buy filters online through outlets like Amazon if you know the proper number and size. 

The designation of filter will likely include the brand name (which may be important, because air filters have small differences that make a world of trouble if you get them wrong) as well as a measurement and a filtration grade. 

The user manual of your unit will have this information in it, if you still have that. If you don’t have the manual or can’t find the designation on the filter itself, then get online and look up the make and model of the furnace. It should be easy to identify which filter is required–and you may be able to order the replacement direct from the manufacturer.

Insert the New Air Filter

The new AC filter goes back into the small door the same way that the other was pulled out. Make sure that you’re putting it in the right way (make a note of which side was up when you pulled it out.) It should fit easily, but firmly with little give. 

It would be wise to take a marker and write on the side of the filter the date on which you replaced it. That way you won’t be left wondering the next time you have to replace it.

Maintain Your Air Filter Regularly 

Having recorded the date you replaced it, it might be worthwhile to put a reminder in your phone or on your calendar to replace the filter in the recommended time (usually three to four months; the manufacturer’s website or the filter packaging will tell you).