Selecting 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 vital part in keeping its system operating safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, enabling potentially harmful particles to move through your home. It also slows 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 only about keeping your furnace working efficiently. It’s also about providing good indoor air quality for your residence.
Your health is important to the heating pros at Home Furniture, Plumbing & Heating. We've long focused on improving indoor air quality in Kankakee. 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?
When to Replace the Air Filter in Your Furnace
Experts stress it's critical to replace dirty air filters in a furnace or air conditioner routinely. Dirty 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 every month and replacing it if it’s dirty. You’ll know if the filter needs to be changed because it will be gray or black from dirt or dust. Those who have pets that shed will probably have to replace their furnace air filter more often, because an effective 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 located in the return air duct or blower compartment before the return air reaches the furnace. This makes sure air entering the system is filtered before it moves through the furnace components and is heated.
Depending on the furnace brand, the filter may be positioned on the right, left, bottom or in some cases, on the inside of the furnace. It's generally housed inside of a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for facts concerning filter location of your particular brand and model of furnace.
Are Air Filters and Furnace Filters the Same Thing?
The easy answer is, yes. In HVAC, a furnace filter and an air filter or air conditioning filter are basically the same thing. While they might be called different things based on the current season— warm or chilly months—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, making sure the air flowing through your home is clean and safe.
What Is a MERV Rating and What MERV Rating Should I Have?
Once you locate your old furnace filter and figure out when it should be replaced, it’s time to pick a replacement. That means picking the level of filtration that you need. One method to do this is by selecting an appropriate MERV rating for your needs.
MERV is short 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 higher numbers indicating a greater ability to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good balance between having adequate indoor air quality without needlessly restricting airflow. However, people with some health conditions could need to purchase a filters with a higher MERV rating.
How to Place the Air Filter in a Furnace or Air Conditioner
Installing an air filter in a furnace or air conditioner the proper way is crucial for the efficient operation of the system. Air filters are supposed to face a specific direction, indicated by an arrow printed on the side of the filter frame. The filter should be placed in the unit with this arrow pointing toward the furnace or air conditioning unit, which is the direction of the airflow. If you're doubtful 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, be sure that the arrow points in the direction of the furnace or AC.
Many people struggle with 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 go. A handy time to do this is during a regular furnace maintenance call.
Changing Your Furnace's Air Filter
Changing the filter on your furnace or AC is a quick and easy process. Here is a step-by-step rundown of how to take out a dirty air filter and swap it for a new one:
- Turn off your furnace: Make a point to shut off your furnace before starting the process.
- Look for the furnace filter: Typically, the filter is found within 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 replacement filter to point in the same direction.
- Take out the old filter: Be diligent not to knock out any dust or debris.
- Document the date: Write down the date of replacement 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 in the direction of 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 securely and close any latches or clips that secure it in place.
- Turn on your furnace: Once the clean filter is properly 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 quit working or decrease its lifespan. Changing your furnace or air conditioning filter is one of the simplest things you can do to keep your system operating efficiently.