
Picking out the correct 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 function in keeping its system running safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, permitting 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 only about keeping your furnace operating efficiently. It’s also about creating excellent indoor air quality for your home.
The quality of the air your family breathes is important to the HVAC pros at Pepper AC & Heat. We've long been dedicated to bettering indoor air quality in Justin. 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?
How Often to Replace the Air Filter in a Furnace
It is critical to replace dirty air filters in a furnace or air conditioner periodically. Dirt-clogged filters cause the system to worker harder than it should because it takes extra effort to move air through the plugged-up filter.
Officials recommend examining your furnace filter monthly 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. People who have pets will probably need to replace their furnace air filter more often, because a quality 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 usually located in the return air duct or blower compartment before the return air gets to the furnace. This ensures air being pulled into the system is filtered before it passes through the furnace components and is heated.
Depending on the type of furnace, the filter may be found on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed within a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for 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 conditioning filter are effectively identical. 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 residence.
They each eliminate dust, allergens, bacteria and other airborne debris from the air that is drawn into the furnace and air conditioning system, ensuring 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 changed, it’s time to select a replacement. That means determining the level of filtration that you need. One approach to this is by choosing 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 bigger numbers indicating enhanced capabilities to filter smaller particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having good indoor air quality without needlessly restricting airflow. However, people with some health conditions may need to use a filter 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 the proper way is crucial for the efficient operation of the heating or cooling system. Air filters have a specific 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 AC, which is the direction of the airflow. If you're unsure about the airflow direction, try to remember that air always moves from the return duct towards the heat or cooling source. Therefore, make sure the arrow points in the direction of the furnace or air conditioner.
Many people struggle with which direction to face their air filter. To help remember, consider taking a quick picture with your cellular 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 be installed. A handy time to ask about this is during a scheduled 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 rundown of how to retreive a dirty air filter and replace it with a new one:
- 1. Turn off your furnace: Make a point to shut off your furnace before beginning the process.
- Find the furnace filter: Typically, the filter is found 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 new filter to point the same way.
- Take out the old filter: Be diligent not to knock out any dust or debris.
- Record the date: Write down the date you changed filters on the new filter's frame. This will help you 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 at 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 lock it in the compartment.
- Turn on your furnace: Once the replacement filter is safely in place, 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 limit its lifespan. Changing your furnace or air conditioner filter is one of the easiest things you can do to keep your system working efficiently.