Selecting 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 critical role in keeping its system running safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, allowing potentially harmful particles to move through your home. It also limits airflow, which can damage your furnace and reduce its life span.
Making sure your furnace uses a clean filter that is suitable for your needs is not merely about keeping your furnace running efficiently. It’s also about delivering excellent indoor air quality for your home.
The health of your family is important to the heating pros at Fleming Heating & Air Conditioning Inc. We've long worked with an eye on enhancing indoor air quality in South Beloit and Belvidere. 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 pull air through the plugged-up filter.
Officials recommend inspecting your furnace filter every month 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 will probably 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 commonly located in the return air duct or blower compartment before the return air gets to 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 type of furnace, the filter may be positioned on the right, left, bottom or in some cases, within the furnace. It's generally housed within a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for important information about 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 air conditioner filter are essentially the same thing. While people may call them different things based on the current season— hot or cold—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 distributed throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you track down your old furnace filter and determine when it should be replaced, it’s time to select a replacement. That means deciding on the level of filtration that you need. One approach to this is by selecting an appropriate MERV rating for your needs.
MERV is an abbreviation 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 tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having healthy indoor air quality without overly 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
Putting an air filter in a furnace or air conditioner correctly is necessary for the efficient operation of the system. Air filters are designed to be installed in a certain direction, indicated by an arrow written on the side of the filter frame. The filter should be installed with this arrow pointing at the furnace or air conditioner, 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 towards the heat or cooling source. Therefore, make certain the arrow points toward the furnace or air conditioning unit.
Many people struggle with which direction to face an air filter. To help remember, consider taking a quick 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 point. A handy time to inquire 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 quick and easy process. Here is a step-by-step breakdown of how to retreive a dirty air filter and replace it with a new one:
- 1. Turn off your furnace: Make sure to switch off your furnace before starting up the process.
- Look for the furnace filter: Typically, the filter is located in 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 new filter to point similarly.
- Slide out the old filter: Be mindful not to knock out any dust or dirt.
- Document 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 the next change.
- Slide 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 lock it in place.
- Turn on your furnace: Once the new filter is properly in place, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The short answer is, yes, a dirty air filter can cause a furnace to stop working or shorten its lifespan. Changing your furnace or air conditioning filter is one of the best things you can do to keep your system working effectively.