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 vital role in keeping its system working safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, permitting potentially harmful particles to flow through your home. It also restricts airflow, which can damage your furnace and shorten its life span.
Making certain your furnace uses a clean filter that is appropriate for your needs is not merely about keeping your furnace running efficiently. It’s also about creating good indoor air quality for your residence.
The quality of the air your family breathes is important to the heating and cooling pros at LTS Plumbing & Heating Inc.. We've long focused on bettering indoor air quality in Shamokin and Sunbury. 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
It is important to replace dirty air filters in a furnace or air conditioner regularly. Dirty filters cause the system to worker harder than it should because it takes extra effort to move air through the plugged-up filter.
Officials suggest inspecting your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if your filter needs changing because it will be gray or black from dirt or dust. Homeowners who have pets that shed will very likely want to replace their furnace air filter more often, because a good 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 usually found in the return air duct or blower compartment before the return air goes back into the furnace. This makes sure air being pulled into the system is filtered before it goes through the furnace components and is heated.
Depending on the type of furnace, the filter may be located on the right, left, bottom or in some cases, within the furnace. It's generally housed in a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for facts about filter location of the furnace in your home.
Is My Furnace Filter Just a Type of Air Filter?
The straightforward answer is, yes. In HVAC, a furnace filter and an air filter or air conditioner filter are basically the same. While people might refer to them differently based on the current season— hot or cold—they are all filters that clean the air in your residence.
They each eliminate dust, allergens, bacteria and other particulates from the air that is drawn into the furnace and air conditioning system, ensuring the air circulating throughout your home is clean and safe.
What Is the MERV Rating System 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 way to do that is by picking an appropriate MERV rating for your needs.
MERV is an abbreviation for Minimum Efficiency Reporting Values. The MERV rating measures the effectiveness of air filters at trapping airborne molecules. The rating scale ranges from 1 to 20, with greater numbers indicating enhanced capabilities 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 unnecessarily restricting airflow. However, people with specific health conditions might need to purchase a filters with a higher MERV rating.
Where to Insert the Air Filter in a Furnace or AC Unit
Putting an air filter in a furnace or air conditioner the proper way is important for the efficient operation of the unit. 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 placed in the unit with this arrow pointing toward the furnace or AC, which is the direction of the airflow. If you're unsure about the airflow direction, remember that air always moves from the return duct towards 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 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 go. A handy time to ask about this is during a routine furnace maintenance appointment.
How to Change a Furnace Air Filter
Switching out the filter on your furnace or air conditioning system is a simple process. Here is a step-by-step list of how to remove a dirty air filter and swap it for a new one:
- Turn off your furnace: Be sure to turn off your furnace before starting the process.
- Look for the furnace filter: Typically, the filter is positioned 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 similarly.
- Take out the old filter: Be diligent 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 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 the old filter you are replacing.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that lock it in the compartment.
- Turn on your furnace: Once the replacement filter is completely installed, 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 cease working or shorten its lifespan. Changing your furnace or air conditioning filter is one of the easiest things you can do to keep your system working effectively.