Choosing the proper furnace filter and changing it when it gets dirty is as important to your HVAC system as changing the oil is to your car. Each plays a critical function in keeping its system running safely, efficiently and for a long time.
A dirty furnace filter loses its effectiveness, enabling potentially harmful particles to move through your home. It also restricts airflow, which can damage your furnace and reduce its life span.
Ensuring your furnace uses a clean filter that is appropriate for your needs is not just about keeping your furnace running efficiently. It’s also about delivering excellent indoor air quality for your household.
The health of your family is important to the HVAC professionals at Interstate Heating & Air Conditioning. We've long been dedicated to improving indoor air quality in Omaha. Here, we’ve answered common questions about HVAC filters, including that especially tricky question of what direction do you point a filter in your furnace or air conditioner?
How Often to Replace the Air Filter in a Furnace
It is critical to replace dirty air filters in a furnace or air conditioner regularly. Dirt-clogged filters cause the system to worker harder than it should because it takes extra work to force air through the plugged-up filter.
Officials recommend inspecting your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if it is dirty because it will filled with dirt or dust. Homeowners who have pets will probably need to replace their furnace air filter more often, because a quality air filter will trap pet hair circulating in a home.
Where Is the Air Filter in My Furnace?
In general, a furnace air filter is normally installed in the return air duct or blower compartment before the return air gets to the furnace. This is so air flowing into the system is filtered before it moves through the furnace components and is heated.
Depending on the furnace model, the filter may be found on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed within a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for information concerning filter location of your particular brand and model of furnace.
Is My Furnace Filter Just a Type of Air Filter?
The straightforward answer is, yes. In HVAC, a furnace filter and an air filter or air conditioning filter are effectively the same thing. While people may call them different things based on the current season— warm or chilly months—they are all filters that clean the air in your HVAC system.
They each remove dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, making certain the air flowing through your home is clean and safe.
What Is the MERV Rating System and What Rating Is Best for Me?
Once you track down your old furnace filter and decide when it should be replaced, it’s time to select a replacement. That means determining the level of filtration that you need. One method to do this is by choosing an appropriate MERV rating for your needs.
MERV is an abbreviation for Minimum Efficiency Reporting Values. The MERV rating calculates the effectiveness of air filters at trapping airborne molecules. The rating scale ranges from 1 to 20, with higher numbers indicating a greater ability to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having adequate indoor air quality without overly restricting airflow. However, people with certain health conditions may need to use a filter with a higher MERV rating.
Where to Insert the Air Filter in a Furnace or Air Conditioning System
Installing an air filter in a furnace or air conditioner the proper way is crucial for the efficient operation of the unit. Air filters are designed to be installed in a particular direction, indicated by an arrow written on the side of the filter frame. The filter should be installed with this arrow pointing at the furnace or air conditioning unit, which is the direction of the airflow. If you're not sure about the airflow direction, try to remember that air always moves from the return duct and then to the heat or cooling source. Therefore, be sure that the arrow points toward the furnace or air conditioner.
Many people struggle with which direction to install an air filter. To help remember, consider taking a quick picture with your cellular phone after the filter has been accurately installed by a professional. Or, you also could ask a technician to use a marker to write on the outside of your furnace which direction the filter should go. A perfect time to ask about this is during a regular furnace maintenance visit.
How to Replace Your Furnace Air Filter
Switching out the filter on your furnace or air conditioning system is a simple process. Here is a step-by-step breakdown of how to remove a dirty air filter and replace it with a new one:
- Turn off your furnace: Make sure to switch off your furnace before starting the process.
- Locate the furnace filter: Typically, the filter is found in the furnace or in the air return vent. Make a mental note or write down which direction the arrow points on the filter, because you’ll want the arrow on the replacement filter to point similarly.
- Remove the old filter: Be careful not to knock out any dust or particles.
- Note the date: Write down the date you changed filters on the new filter's frame. This will help you keep track of when it's time for the next change.
- Put in new filter: Put in the new filter with the arrow pointing at the furnace, which is the direction of airflow and should be the same direction the arrow pointed on your last filter.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the replacement filter is safely secured, you can turn your furnace back on.
Can a Dirty Air Filter Cause Problems for a Furnace?
The simple answer is, yes, a dirty air filter can cause a furnace to stop working or limit its lifespan. Changing your furnace or AC filter is one of the easiest things you can do to keep your system working efficiently.