Selecting 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 role in keeping its system operating safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, allowing potentially harmful particles to circulate through your home. It also limits airflow, which can damage your furnace and decrease its life span.
Making sure your furnace uses a clean filter that is appropriate for your needs is not just about keeping your furnace operating efficiently. It’s also about creating good indoor air quality for your residence.
Your health is important to the heating specialists at Cooler Tymes LLC. We've long focused on improving indoor air quality in Litchfield Park. Here, we’ve answered frequent questions about HVAC filters, including that particularly 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 periodically. Dirty filters cause the system to worker harder than it should because it takes extra effort to force air through the plugged-up filter.
Officials recommend inspecting your furnace filter monthly and replacing it if it’s dirty. You’ll know if the filter needs to be changed because it will coated with dirt or dust. Those who have pets will likely have to replace their furnace air filter more often, because an effective 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 usually installed in the return air duct or blower compartment before the return air gets to the furnace. This ensures air entering the system is filtered before it passes through the furnace components and is heated.
Depending on the type of furnace, the filter may be located on the right, left, bottom or in some cases, inside the furnace. It's typically housed inside of a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for details regarding filter location of the furnace in your home.
Is a Furnace Filter the Same as an Air Filter?
The easy 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 get rid of dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, making sure the air distributed throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you find your old furnace filter and decide when it should be changed, it’s time to pick a replacement. That means determining the level of filtration that you need. One way to do that is by choosing 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 contaminants. The rating scale ranges from 1 to 20, with bigger numbers indicating a greater ability to filter smaller particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good balance between having good indoor air quality without unnecessarily restricting airflow. However, people with some health conditions might need to use a filter with a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or Air Conditioner
Positioning an air filter in a furnace or air conditioner the proper way is crucial for the efficient operation of the system. 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 AC, which is the direction of the airflow. If you're not sure about the airflow direction, it may be helpful to remember that air always moves from the return duct to the heat or cooling source. Therefore, make certain the arrow points at the furnace or air conditioning unit.
Many people have difficulty remembering which direction to point their system's air filter. To help remember, consider taking a quick 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 be installed. A perfect time to do this is during a scheduled furnace maintenance visit.
How to Change a Furnace Air Filter
Changing the filter on your furnace or air conditioning system is an easy process. Here is a step-by-step rundown of how to take out a dirty air filter and replace it with a new one:
- 1. Turn off your furnace: Be sure to switch off your furnace before starting up the process.
- Find the furnace filter: Typically, the filter is positioned 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 clean filter to point the same way.
- Slide out the old filter: Be diligent not to knock out any dust or dirt.
- 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 you to change it again.
- Slide 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 your last filter.
- Secure the filter: Make sure the new filter fits nicely and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the new filter is safely secured, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The simple answer is, yes, a dirty air filter can cause a furnace to cease working or decrease its lifespan. Changing your furnace or AC filter is one of the best things you can do to keep your system operating efficiently.