Selecting the right 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 crucial part in keeping its system operating safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, enabling potentially harmful particles to flow through your home. It also slows airflow, which can damage your furnace and shorten its life span.
Ensuring your furnace uses a clean filter that is suitable for your needs is not just about keeping your furnace working efficiently. It’s also about delivering healthy indoor air quality for your household.
The quality of the air your family breathes is important to the HVAC pros at J.L. Brady Company LLC. We've long worked with an eye on improving indoor air quality in Moline. Here, we’ve answered frequent 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
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 move air through the plugged-up filter.
Officials advise inspecting your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if it is dirty 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 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 normally located in the return air duct or blower compartment before the return air gets to the furnace. This is so air flowing into the system is filtered before it passes 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, on the inside of the furnace. It's usually housed in a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information regarding filter location of your particular brand and model of furnace.
Is a Furnace Filter the Same as an Air Filter?
The simple answer is, yes. In HVAC, a furnace filter and an air filter or AC 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 remove dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, making sure the air circulating 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 figure out when it should be substituted for a clean one, it’s time to pick 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 calculates the effectiveness of air filters at trapping airborne molecules. The rating scale ranges from 1 to 20, with higher numbers indicating enhanced capabilities to filter smaller particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good balance between having good indoor air quality without needlessly restricting airflow. However, people with specific health conditions may need a a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or Air Conditioner
Installing an air filter in a furnace or air conditioner correctly is necessary for the efficient operation of the unit. Air filters have a certain direction, indicated by an arrow written on the side of the filter frame. The filter should be put in 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, try to remember that air always moves from the return duct and then to the heat or cooling source. Therefore, make sure the arrow points at the furnace or air conditioning unit.
Many people have difficulty remembering which direction to install their system's air filter. To help remember, consider snapping a quick photo with your cell phone after the filter has been properly 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 great time to ask about this is during a scheduled furnace maintenance call.
How to Change a Furnace Air Filter
Switching out the filter on your furnace or air conditioner is an easy 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: Be sure to switch off your furnace before starting the process.
- Locate the furnace filter: Typically, the filter is located in 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 in the same direction.
- Take out the old filter: Be mindful not to knock out any dust or dirt.
- Record the date: Write down the date you changed filters on the new filter's frame. This will make it easier to 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 correctly and close any latches or clips that secure it in place.
- Turn on your furnace: Once the new filter is completely secured, 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 reduce its lifespan. Changing your furnace or AC filter is one of the best things you can do to keep your system working effectively.
