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Change Air Filter

Replacing an air filter in your forced air furnace or air conditioner is something you always hear about when talking about maintaining your home’s HVAC system. Yes, it is an important part to your system’s upkeep, and the good news is that it’s very easy to change an air filter, and it generally doesn’t cost you much.

What does your air filter do anyway?

Your forced-air system is designed to push heated or chilled air around your house. Most of this air gets recirculated over and over. And no matter how clean you keep your home, your inside air is bound to have plenty of dust, pollen,  pet dander and a host of allergens floating around your house. Nice thought, right? Well, that’s where your air filter comes in. It’s designed specifically to capture many of these air “pollutants” when your home’s air passes through your furnace and air conditioning system’s air filter. Thankfully, air filters today are pretty good at trapping a lot of this stuff…as long as they are clean. This means changing out air filters often (even before you think they need it)!

How often you replace an air filter can depend on how much you use your air. One good rule of thumb when heating and cooling your house year-round is to change out the air filter once per month. If you have lighter use, simply check the air filter after a month by removing it and holding it up to a bright light source. If light has a hard time passing through it (compare to a new air filter), then it’s time to change your air filter. Use your common sense too on when to change the air filter, remembering that the dirtier the air filter is, the harder it is for the filter to collect dust and other artifacts from your home’s air. A dirty air filter can also put undo strain on your blower’s motor, which can lead to repair or a shortened life expectancy. Expensive? You betcha.

How to change an air filter?

Your home’s air filter does the hard part; you have the easy part: change the air filter when it gets dirty. This really is an easy task, and probably the hardest thing about it is remembering to actually change it out! If you go to your basement or garage (i.e., wherever your furnace is), simply find the air filter compartment and remove it’s cover. Depending on your type of blower, your filter could be located on the bottom beneath the actual blower or on the side of your furnace. Either way, it will always be housed between your blower and the air return duct. Remember to consult the owner’s manual of your particular model to locate and properly remove the compartment door as some doors may need to be unscrewed or pried open in a particular way. Now, take hold of your existing air filter and pull it out, being careful not to get it’s cardboard sides caught on any metal edges, screws or other parts.

Now, just insert your new air filter in the opposite manner of how you removed the old air filter, being sure to align the arrows imprinted on the air filter’s side the same way. These arrows indicate the flow of air in your system, and yes, it does matter which way the air filter goes in!

What’s my air filter size and type?

If you don’t have a new air filter because you’re not sure which kind or size you need, then you’re probably removing your air filter to determine just what you need. Luckily, air filters always have their sizes labeled on them, e.g. 20″ x 1″. Match the new air filter you’re going to buy to this…unless the last person inserted the wrong size. You’ll know this if it looks like the air filter was forced into place for example. If there is no air filter and you don’t have a manual you can try looking up your make and model online or get a tape measure and write the dimensions down of the air duct opening that needs to be covered. Your local home store can help you choose the right replacement air filter.

One tip when buying air filters: Get packs of them. This will be cheaper and make life easier when replacing air filters throughout the year. In fact, if you really want to be organized, you can buy 12 or more, then mark with a pen, which month each air filter should be installed.

Now, if your system has an electrostic air filter, then you never have to replace an air filter! In fact, you have what’s called a life-time or permanent air filter. These just need to be removed, inspected and cleaned before reusing. Follow the directions on the air filter for more information. Happy clean air breathing!

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