Picking out the right furnace filter and changing it when it becomes 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, allowing potentially harmful particles to move through your home. It also slows airflow, which can damage your furnace and reduce its life span.
Ensuring your furnace uses a clean filter that is ideal for your needs is not only about keeping your furnace working efficiently. It’s also about creating healthy indoor air quality for your residence.
The quality of the air your family breathes is important to the heating specialists at Service Max Heating & Air Conditioning. We've long been dedicated to bettering indoor air quality in Arlington. Here, we’ve answered common 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
Experts stress it's vital 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 force 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 the filter needs to be changed because it will be gray or black from dirt or dust. Those who have pets that shed will likely want 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 normally located in the return air duct or blower compartment before the return air goes back into the furnace. This ensures air flowing into the system is filtered before it goes through the furnace components and is heated.
Depending on the furnace brand, the filter may be found on the right, left, bottom or in some cases, inside the furnace. It's typically housed in a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for facts concerning 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 AC filter are effectively 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 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 Is a MERV Rating and What MERV Rating Do I Need?
Once you find your old furnace filter and determine when it should be replaced, it’s time to choose a replacement. That means determining the level of filtration that you need. One approach to 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 molecules. The rating scale ranges from 1 to 20, with greater numbers indicating the power to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having adequate indoor air quality without needlessly restricting airflow. However, people with some health conditions may need to purchase a filters 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 correctly is crucial for the efficient operation of the unit. Air filters have a particular direction, indicated by an arrow printed on the side of the filter frame. The filter should be put in with this arrow pointing in the direction of the furnace or air conditioner, which is the direction of the airflow. If you're not sure 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 toward the furnace or air conditioning unit.
Many people are confused by which direction to point an air filter. To help remember, consider taking a 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 ask about this is during a routine furnace maintenance visit.
How to Change a Furnace Air Filter
Switching out 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:
- 1. Turn off your furnace: Make sure to switch 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. Take note of which direction the arrow points on the filter, because you’ll want the arrow on the clean filter to point similarly.
- Remove the old filter: Be mindful not to knock out any dust or dirt.
- Record the date: Write down the date of replacement on the new filter's frame. This will make it easier to keep track of when it's time for you to change it again.
- Put 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 your last filter.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the clean filter is properly in place, 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 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 running effectively.