Selecting the proper furnace filter and changing it when it is 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 operating safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, allowing potentially harmful particles to circulate through your home. It also restricts airflow, which can damage your furnace and shorten its life span.
Making certain 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 delivering excellent indoor air quality for your household.
The health of your family is important to the HVAC specialists at ACE Solutions. We've long focused on improving indoor air quality in Hasbrouck Heights. 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's 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 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 your filter needs changing because it will coated with dirt or dust. People who have pets that shed will likely have to replace their furnace air filter more often, because a quality air filter will trap pet hair circulating in a home.
How to Find the Furnace's Air Filter
In general, a furnace air filter is commonly installed in the return air duct or blower compartment before the return air goes back into the furnace. This makes sure 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 positioned on the right, left, bottom or in some cases, inside the furnace. It's generally housed within a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for information about filter location of the furnace in your home.
Is a Furnace Filter the Same as an 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 they might be called different things based on the current season— summer or winter—they are all filters that clean the air in your home.
They each eliminate dust, allergens, bacteria and other particulates 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 Are MERV Ratings and What Rating Is Best for Me?
Once you locate your old furnace filter and determine when it should be replaced, it’s time to select a replacement. That means picking the level of filtration that you need. One approach to this is by choosing an appropriate MERV rating for your needs.
MERV is short for Minimum Efficiency Reporting Values. The MERV rating measures the effectiveness of air filters at trapping airborne particles. The rating scale ranges from 1 to 20, with greater 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 good indoor air quality without unnecessarily 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 Conditioner
Installing an air filter in a furnace or air conditioner properly is important for the efficient operation of the unit. Air filters are supposed to face a particular direction, indicated by an arrow located on the side of the filter frame. The filter should be placed in the unit with this arrow pointing at the furnace or air conditioner, which is the direction of the airflow. If you're unsure 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 in the direction of the furnace or AC.
Many people are confused by which direction to face their system's air filter. To help remember, consider taking a picture with your mobile 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 great time to ask about this is during a scheduled furnace maintenance appointment.
Changing Your Furnace's Air Filter
Replacing the filter on your furnace or air conditioner is a simple process. Here is a step-by-step breakdown of how to remove a dirty air filter and exchange it for a new one:
- Turn off your furnace: Be sure to shut off your furnace before beginning the process.
- Locate the furnace filter: Typically, the filter is positioned inside 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.
- Slide out the old filter: Be diligent not to knock out any dust or dirt.
- Note 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.
- 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 the old filter you are replacing.
- 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 clean filter is properly installed, you can turn your furnace back on.
Can a Dirty Air Filter Damage My Furnace?
The simple answer is, yes, a dirty air filter can cause a furnace to stop working or reduce its lifespan. Changing your furnace or air conditioning filter is one of the best things you can do to keep your system operating effectively.