Your AC filter is an important tool for reducing your home’s allergens and keeping it a little more dust-free. Many HVAC filters actually say on the packaging that a once-a-month schedule is a good idea to keep dust and allergens to a minimum. You probably already know you should change your filter on a regular basis, but what you may not be aware of is exactly how often that frequency can vary from household to household. Here’s what you need to know to keep your home’s air clean — and even save some money, too. (1-inch filters every 30 days, 2-inch every 60 to 90 days, 3-inch every 90 days, and 4 to 5-inch filters every 6 to 9 months).
Some filters last longer than others, so be sure to take a look at the packaging. All filters have a Minimum Efficiency Reporting Value (MERV) rating. The higher the MERV number, the better quality the filter is, meaning it can hold contaminates better and last longer. The only downside to picking a filter with a high MERV rating is that it can slow down the airflow in your AC unit. The best choice is a balance between good quality and good airflow, which is typically a filter that has a MERV rating of 6 to 8. If you have a high-efficiency AC and a large enough air duct system you may get away with a higher rating. Have a qualified technician in your area inspect the ducting, the size, and the efficiency of your system just to be sure your system can operate with as high a MERV filter as you can get for the best air quality and dust-free home possible.
Now that you have good filters, there’s a mix of factors that affect how often you replace them. Every three weeks is a good rule of thumb if you have multiple pets, live in a very dusty or polluted area, or have severe allergies (Note if you have severe allergies you should also look to add a whole-home air treatment system to help).
On the other hand, if you rarely use your AC, you can wait up to 30 to 60 days to change the filter (never exceed the manufacturers’ recommendations on the filter packaging). A good way to remember is to switch it out at least once or twice a season.
There are a lot of variables, right? The only way you can be sure you’re changing your filter at the right time for your home is to give it a peek once a week to get a feel for how quickly it gets dirty. Hold it up to the light and if you can’t see light through the filter, then it is definitely past time for a new one.
Not only does changing your AC filter help your home’s air conditions, but it can also save you money. Replacing a clogged air filter with a new one can lower the air conditioner’s energy consumption around 5 to 10 percent, according to the US Department of Energy. Less energy consumed equals a lower power bill, which is a big win in the dead of summer when those electricity costs normally spike.