Selecting the right furnace filter and changing it when it becomes dirty is as important to your HVAC system as changing the oil is to your car. Each plays a critical part in keeping its system running safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, enabling potentially harmful particles to circulate through your home. It also restricts airflow, which can damage your furnace and decrease its life span.
Ensuring your furnace uses a clean filter that is appropriate for your needs is not merely about keeping your furnace operating efficiently. It’s also about creating healthy indoor air quality for your home.
The quality of the air your family breathes is important to the heating specialists at Siloam Springs Heating & AC. We've long focused on enhancing indoor air quality in Siloam Springs. 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 important to replace dirty air filters in a furnace or air conditioner periodically. Soiled filters cause the system to worker harder than it should because it takes more energy to move air through the plugged-up filter.
Officials recommend inspecting your furnace filter monthly and replacing it if it’s dirty. You’ll know if your filter needs changing because it will be gray or black from dirt or dust. People who have dogs and cats will probably have to replace their furnace air filter more often, because a quality air filter will trap pet hair circulating in a home.
Locating Your Furnace's Air Filter
In general, a furnace air filter is usually installed in the return air duct or blower compartment before the return air goes back into the furnace. This ensures air flowing into the system is filtered before it goes through the furnace components and is heated.
Depending on the furnace model, the filter may be located on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed in a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for details about filter location of the furnace in your home.
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 AC filter are effectively the same thing. While they might be called different things based on the current season— hot or cold—they are all filters that clean the air in your home.
They each get rid of dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, ensuring the air distributed throughout your home is clean and safe.
What Are MERV Ratings and What Rating Is Best for Me?
Once you find your old furnace filter and figure out when it should be changed, it’s time to pick a replacement. That means picking the level of filtration that you need. One approach to this is by picking an appropriate MERV rating for your needs.
MERV stands for Minimum Efficiency Reporting Values. The MERV rating indicates the effectiveness of air filters at trapping airborne molecules. The rating scale ranges from 1 to 20, with higher numbers indicating the power to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having good indoor air quality without needlessly restricting airflow. However, people with some health conditions might need a 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 properly is important for the efficient operation of the unit. Air filters have a certain direction, indicated by an arrow written on the side of the filter frame. The filter should be placed in the unit with this arrow pointing in the direction of the furnace or air conditioner, which is the direction of the airflow. If you're unsure about the airflow direction, try to remember that air always moves from the return duct towards the heat or cooling source. Therefore, be sure that the arrow points toward the furnace or AC.
Many people are confused by which direction to point an air filter. To help remember, consider taking a picture with your cell phone after the filter has been correctly 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 point. A perfect time to do this is during a regular furnace maintenance call.
Changing Your Furnace's Air Filter
Switching out the filter on your furnace or AC is an easy process. Here is a step-by-step breakdown of how to retreive a dirty air filter and exchange it for a new one:
- Turn off your furnace: Be sure to shut off your furnace before starting up the process.
- Find the furnace filter: Typically, the filter is located in the furnace or in the air return vent. Make note of which direction the arrow points on the filter, because you’ll want the arrow on the new filter to point similarly.
- Take out the old filter: Be mindful not to knock out any dust or debris.
- Note the date: Write down the date you changed filters on the new filter's frame. This will make it easier to keep track of when it's time for another replacement.
- Put in new filter: Put in the new filter with the arrow pointing toward the furnace, which is the direction of airflow and should be the same direction the arrow pointed on the dirty filter you just removed.
- Secure the filter: Make sure the new filter fits nicely and close any latches or clips that lock it in place.
- Turn on your furnace: Once the new filter is safely in place, you can turn your furnace back on.
Will a Dirty Air Filter Cause Problems for a Furnace?
The short answer is, yes, a dirty air filter can cause a furnace to stop working or limit its lifespan. Changing your furnace or air conditioning filter is one of the simplest things you can do to keep your system working effectively.
