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 function in keeping its system operating 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 slows airflow, which can damage your furnace and decrease its life span.
Making sure your furnace uses a clean filter that is ideal for your needs is not merely about keeping your furnace operating efficiently. It’s also about delivering healthy indoor air quality for your household.
The health of your family is important to the heating and cooling pros at West Jefferson Plumbing and Heating, Inc.. We've long worked with an eye on bettering indoor air quality in West Jefferson. 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?
When Should I Replace My Furnace Air Filter?
It is vital 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 more energy to move air through the plugged-up filter.
Officials suggest inspecting your furnace filter monthly 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. Homeowners who have pets that shed will very likely have to replace their furnace air filter more often, because a good air filter will trap pet hair circulating in a home.
Locating Your Furnace's Air Filter
In general, a furnace air filter is commonly located in the return air duct or blower compartment before the return air reaches the furnace. This ensures air flowing into the system is filtered before it passes 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, within the furnace. It's usually housed inside of a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information 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 essentially the same thing. While people might refer to them differently based on the current season— summer or winter—they are all filters that clean the air in your HVAC system.
They each get rid of dust, allergens, bacteria and other particulates from the air that is drawn into the furnace and air conditioning system, ensuring the air flowing through your home is clean and safe.
What Are MERV Ratings and What MERV Rating Should I Have?
Once you track down your old furnace filter and figure out 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 stands for Minimum Efficiency Reporting Values. The MERV rating measures the effectiveness of air filters at trapping airborne contaminants. The rating scale ranges from 1 to 20, with greater numbers indicating the power to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having healthy indoor air quality without needlessly restricting airflow. However, people with specific health conditions could need a a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or AC Unit
Installing an air filter in a furnace or air conditioner properly is necessary for the efficient operation of the heating or cooling system. Air filters are designed to be installed in a specific direction, indicated by an arrow printed on the side of the filter frame. The filter should be installed with this arrow pointing toward the furnace or air conditioning unit, 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 to the heat or cooling source. Therefore, be sure that 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 cellular 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 do this is during a routine furnace maintenance appointment.
Changing Your Furnace's Air Filter
Switching out the filter on your furnace or AC is an easy process. Here is a step-by-step list of how to take out a dirty air filter and exchange it for a new one:
- Turn off your furnace: Be sure to turn off your furnace before starting up the process.
- Look for the furnace filter: Typically, the filter is positioned 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 clean filter to point in the same direction.
- Slide out the old filter: Be careful not to knock out any dust or particles.
- Document the date: Write down the date you replaced the filter on the new filter's frame. This will help you keep track of when it's time for the next change.
- 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 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 the compartment.
- Turn on your furnace: Once the new filter is safely in place, you can turn your furnace back on.
Can a Dirty Air Filter Damage My Furnace?
The simple 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 simplest things you can do to keep your system running effectively.