Choosing the ideal 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 crucial role in keeping its system operating safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, enabling potentially harmful particles to circulate through your home. It also restricts airflow, which can damage your furnace and reduce its life span.
Making certain 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 good indoor air quality for your residence.
Your health is important to the heating specialists at Stanford Heating & Cooling. We've long focused on bettering indoor air quality in Bloomfield. Here, we’ve answered frequent questions about HVAC filters, including that very tricky question of what direction do you point a filter in your furnace or air conditioner?
When to Replace the Air Filter in Your Furnace
It's critical to replace dirty air filters in a furnace or air conditioner regularly. Soiled 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 inspecting your furnace filter every month 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. Homeowners who have dogs and cats will likely need 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 normally found in the return air duct or blower compartment before the return air reaches the furnace. This makes sure air being pulled into the system is filtered before it moves 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, within the furnace. It's usually housed inside of a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for important information concerning filter location of your particular brand and model of furnace.
Are Air Filters and Furnace Filters the Same Thing?
The simple answer is, yes. In HVAC, a furnace filter and an air filter or air conditioner filter are basically the same. 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 HVAC system.
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 flowing through your home is clean and safe.
What Is a MERV Rating and What Rating Is Best for Me?
Once you track down your old furnace filter and figure out when it should be substituted for a clean one, it’s time to select a replacement. That means picking the level of filtration that you need. One way to do that is by selecting 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 greater numbers indicating a greater ability to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good balance between having good indoor air quality without overly restricting airflow. However, people with specific health conditions might need a a higher MERV rating.
How to Place the Air Filter in a Furnace or AC Unit
Positioning 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 written on the side of the filter frame. The filter should be put in 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 to the heat or cooling source. Therefore, make certain the arrow points at the furnace or air conditioning unit.
Many people struggle with which direction to face their air filter. To help remember, consider snapping a quick photo 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 point. A perfect time to ask about this is during a scheduled furnace maintenance appointment.
How to Replace Your Furnace Air Filter
Replacing the filter on your furnace or AC is a simple process. Here is a step-by-step breakdown of how to remove a dirty air filter and swap it for a new one:
- Turn off your furnace: Make sure to shut off your furnace before starting up the process.
- Find 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 replacement filter to point similarly.
- Take out the old filter: Be diligent not to knock out any dust or debris.
- Record the date: Write down the date you replaced the filter on the new filter's frame. This will help you keep track of when it's time for another replacement.
- Insert 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 correctly and close any latches or clips that secure it in the unit.
- Turn on your furnace: Once the clean filter is completely 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 cease working or decrease its lifespan. Changing your furnace or AC filter is one of the easiest things you can do to keep your system working correctly.
