Picking out the correct 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 part in keeping its system running safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, permitting potentially harmful particles to move through your home. It also restricts airflow, which can damage your furnace and decrease its life span.
Making sure your furnace uses a clean filter that is suitable for your needs is not just about keeping your furnace operating efficiently. It’s also about providing excellent indoor air quality for your home.
The quality of the air your family breathes is important to the HVAC pros at GLR Mechanical. We've long worked with an eye on bettering indoor air quality in Wilkes Barre and Scranton. Here, we’ve answered frequent 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 routinely. Dirt-clogged filters cause the system to worker harder than it should because it takes extra work to pull air through the plugged-up filter.
Officials suggest examining 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. Homeowners who have dogs and cats will very likely want to replace their furnace air filter more often, because a good 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 commonly found in the return air duct or blower compartment before the return air gets to the furnace. This makes sure air entering 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, inside the furnace. It's typically housed in a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information about filter location of your particular brand and model of furnace.
Are Air Filters and Furnace Filters the Same Thing?
The straightforward answer is, yes. In HVAC, a furnace filter and an air filter or air conditioning filter are essentially identical. While people may call them different things based on the current season— summer or winter—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 Are MERV Ratings and What MERV Rating Should I Have?
Once you find your old furnace filter and determine when it should be replaced, it’s time to pick a replacement. That means picking the level of filtration that you need. One way to do that is by picking an appropriate MERV rating for your needs.
MERV stands for Minimum Efficiency Reporting Values. The MERV rating calculates the effectiveness of air filters at trapping airborne particles. The rating scale ranges from 1 to 20, with bigger numbers indicating enhanced capabilities to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having healthy indoor air quality without overly restricting airflow. However, people with specific health conditions might need a 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 unit. Air filters are supposed to face a particular direction, indicated by an arrow printed on the side of the filter frame. The filter should be installed with this arrow pointing toward the furnace or air conditioning unit, which is the direction of the airflow. If you're unsure about the airflow direction, remember that air always moves from the return duct and then to the heat or cooling source. Therefore, make certain the arrow points in the direction of the furnace or AC.
Many people have difficulty remembering which direction to face their system's air filter. To help remember, consider snapping a quick photo 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 handy time to do this is during a scheduled furnace maintenance call.
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 retreive a dirty air filter and exchange it for a new one:
- Turn off your furnace: Make a point to shut off your furnace before starting the process.
- Find the furnace filter: Typically, the filter is positioned within 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 clean filter to point the same way.
- Take out the old filter: Be mindful not to knock out any dust or debris.
- Record the date: Write down the date of replacement on the new filter's frame. This will help your family keep track of when it's time for another replacement.
- Insert new filter: Put in the new filter with the arrow pointing in the direction of 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 lock it in the compartment.
- Turn on your furnace: Once the new filter is completely installed, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The shortest answer is, yes, a dirty air filter can cause a furnace to quit working or limit its lifespan. Changing your furnace or air conditioning filter is one of the best things you can do to keep your system operating efficiently.