Home Air Filter Replacement

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I’ve heard how many West Coast residents are looking for home air filter replacement options or air purifiers to use in their homes, what with fires and all. I get that.

With the fires air quality is poor. This is outside, obviously, but also, inside the home. One of the best ways to improve your indoor air is to replace your home’s forced air filter regularly.

But if you can’t find those whole home air filter replacement options, what are you supposed to do? Well, for years now I’ve had an air filter subscription service.

I’ve used Second Nature, which used to be known as Filter Easy. Second Nature has plenty of home air filters in stock. And, unlike unscrupulous sellers on certain online platforms, they’re not jacking up the prices, simply because they can.

Home air filter replacement subscription

In fact, when you sign up for a home air filter subscription through Second Nature, your first shipment is actually free. After that you’ll pay the same price for home air filter replacements from Second Nature as you would from a home improvement store–sometimes less. Because those filters come to my front door, it saves me time.

And you don’t have to remember to go online to order your new furnace filters or run to the store. When you sign up for Second Nature, you choose how often new filters are sent to you. Have those air filter replacements delivered is super convenient and ensures I never run out of filters and never forget to replace them.

Home Air Filter Replacement: Second Nature

Why you need to replace a filter regularly

If you have a forced air heating or cooling system aka an ac system, you must change filters on a regular basis. Most home air filters replacements run on a three-month or 90-day cycle. I’ve found it’s actually better if I change my filters every month.

Here are some additional home cooling tips.

Why?

First, I have two dogs. That means that with their shedding and tracking in dirt from being outside, my house has more “debris” floating around than other houses.

Second, I like to keep the fan on my forced air system at “on” 24/7. When the fan is on all the time, it is circulating more of that dust and debris through the system. Therefore, changing air filters every month makes more sense.

Third, by changing filters more often, that means that my central air and heating system works more efficiently. That’s because it stays “cleaner.” The end result? My home stays cooler in the summer and warmer in the winter, and I rarely have huge spikes in my energy bills.

Which air filter is best for my home

Also, because I am changing those filters regularly, I am saving money in another way. By keeping a clean filter in my HVAC system at all times, I’m keeping the system clean and make it less likely it will break down or, worse, need to be replaced.

If you do need to have your HVAC system repaired or replaced, like I did in my old house, I would suggest putting a request in through Home Advisor.

Finally, as far as the best air filter for your home, you want to look at something called the MERV rating. That tells you how well (or poorly) the filter is at capturing small particles of dirty air in your home. You want to get an air filter with a MERV rating of at least 13.

Why I keep my furnace and ac on all the time

A long time ago someone told me that keeping the system on “Auto” can actually increase your energy bills. That’s because the system turning on each time the temperature changes from being completely off uses more energy than if the fan is on all the time. I should double check that source and see if that’s still true,

How do I know if my home air filter needs replacing?

There are a couple of ways you can figure out if it’s time for a home air filter replacement. First, have you noticed that your home looks dustier than usual? And I don’t just mean because you’re behind on dusting.

For example, recently I noticed that the walls in our bathroom looked dusty, which I thought was weird. I’ve never really thought of a bathroom as place to collect dust. But when I looked for the source of the dust, I noticed the forced air vent right above where the dust was collecting. That was a clear sign that the filter needed changing.

Second, have you noticed the “sound” of your furnace has changed? In our house the forced air will suddenly sound as if it’s whistling whenever the blower is on. And since, as I mentioned earlier, I like to keep the system at “on” all the time, it’s really noticeable when that sound changes. I’m talking it goes from a non-distinct hum in the background to sounding like you’ve left a window cracked open during a wind storm.

How to change your home air filter

Doing a home air filter replacement or changing your home air filter is pretty easy.

First, turn the system to auto or off. This way you’re not fighting with the forced air to get out the filter. They can be in there pretty tight to begin with. If you’re fighting against air, it will make it harder to get the filter out.

Note the direction of airflow

Second, before you remove the filter, make note of which way the arrow on the air filter is facing. You want to make sure that the arrow on the replacement air filter is facing the same way, too. You can take a Sharpie marker and actually write the arrow on your system so you never forget. Or you can take a picture of the filter and the arrow before your replace it so you know.

air filter replacement
Notice the arrow and which way it’s facing on the air filter.

FYI, according to experts, the air filter arrow should always be facing towards the furnace or the blower and away from the “intake” area of the system. However, in some homes that’s not always easy to figure out, especially if the system was installed in a tight space.

Getting the old filter out

Third, you may need a screwdriver or pair of scissors to gently loosen the filter from its holding position. I find that in some home air systems, the filter gets in there pretty tight. Therefore, getting it out and putting the replacement in becomes a game of tug of war.

Fourth, pull out the filter and put it aside.

Comparing a clean filter with a dirty filter

Fifth, unwrap the new replacement filter from any packaging. You may want to take a moment and compare how dirty the old air filter is with how clean the new one is. We’re talking gray compared with white. Or, in some instances, where there’s a lot of soot, black versus white.

Finally, slide the replacement filter into the slot and turn the system back on.

Why do my air filters get black so fast?

If you happen to be living in an area of the country that’s deal with wildfires, you may discover that your air filters get dirty faster than usual. That’s because the air qualify is so poor, which is no news to you. But it’s a good indication that your home air filter is working to clean your air and why you’ll want to put in replacements more often.

You can get soot building up on your air filters in other ways too:

  • Gas-fire heating
  • Fireplace in the home
  • Burning a lot of candles
dirty air filter
This was a dirty air filter that we’d neglected to change after a few months.

Getting the right size furnace air filter

It’s important that you always buy the correct size air filter for your furnace or forced air system. That’s because you don’t want to have any gaps around the filter. Otherwise, that will cut down on how efficiently the filter cleans your air.

Frustratingly, air filters and ac unit systems come in a variety of sizes. I’ve never lived in a house that had the same size filter slot or requirements. So I could never “stock up” on filters and then just take them with me to another house.

Yet another reason to sign up for a filter subscription service like Second Nature. You’ll only get the filters you need, when you need them.

In fact, if you have a multi-zone home with different air filter needs, you can make it so your Second Nature subscription sends you different size home air filter replacements. You don’t just have to get a single size.

How do I know the size?

Unless you’ve moved into a house that hasn’t been using an air filter–which is stupid and I would be very concerned about the status of that furnace–finding the size of the filter you need is easy. Just look at the filter that’s already in there. On the side–often the same side where you looked to see which way the arrow is facing–you’ll see the size of the filter you need for replacements.

An important note about sizes: Second Nature says there is a small variation in filter sizes but they all fit. From the Second Nature FAQ:

“It might sound strange, but every home air filter is labeled with a “nominal size” that’s different from its actual size. For instance, your filter might actually measure 19-7/8″ x 24-7/8″ x 4-3/8″, but still be labeled “20x25x4.” However, our manufacturers round that last number – the thickness of the filter – up, instead of down. As a result, even if you order a 20x25x4 filter, it may show up on your doorstep labeled as a 20x25x5.”

DIY air filter

I’ve seen images of people taping an air to the back of a box fan. That’s very MacGyver of them but I’ll get it works to help filter out some of the air inside their home. In fact, here is a YouTube video for making a DIY home air filter.

But overall your best bet, if you have a forced air system, is to change those filters regularly. And, again, I would strongly recommend that you sign up for the FilterEasy–now Second Nature– filter subscription service to save time and money on this household task. Remember: your first shipment is free.

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