Selecting the ideal 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 running safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, allowing potentially harmful particles to flow through your home. It also slows airflow, which can damage your furnace and shorten its life span.
Making sure your furnace uses a clean filter that is appropriate for your needs is not merely about keeping your furnace working efficiently. It’s also about delivering excellent indoor air quality for your home.
The quality of the air your family breathes is important to the heating and cooling pros at Forster Heating. We've long worked with an eye on enhancing indoor air quality in Auburn. 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?
How Often to Replace the Air Filter in a Furnace
It is critical to replace dirty air filters in a furnace or air conditioner routinely. 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 recommend examining 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. Those who have pets will very likely have to replace their furnace air filter more often, because an effective 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 installed in the return air duct or blower compartment before the return air goes back into the furnace. This is so air flowing 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 found on the right, left, bottom or in some cases, inside the furnace. It's usually housed in a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for facts 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 basically identical. While they might be called different things based on the current season— warm or chilly months—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 circulating throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you locate your old furnace filter and determine when it should be substituted for a clean one, it’s time to pick a replacement. That means picking 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 contaminants. The rating scale ranges from 1 to 20, with bigger numbers indicating a greater ability to filter smaller particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having adequate indoor air quality without unnecessarily restricting airflow. However, people with specific health conditions could need to use a filter 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 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 placed in the unit with this arrow pointing in the direction of the furnace or air conditioning unit, which is the direction of the airflow. If you're not sure about the airflow direction, it may be helpful to remember that air always moves from the return duct to the heat or cooling source. Therefore, be sure that the arrow points in the direction of the furnace or air conditioner.
Many people have difficulty remembering which direction to install an air filter. To help remember, consider taking a 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 great time to do this is during a scheduled 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 rundown of how to take out a dirty air filter and replace it with a new one:
- 1. Turn off your furnace: Make a point to switch off your furnace before beginning the process.
- Locate the furnace filter: Typically, the filter is found 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 replacement filter to point in the same direction.
- Slide out the old filter: Be careful 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.
- Insert new filter: Put in the new filter with the arrow pointing toward 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 nicely and close any latches or clips that hold it in the compartment.
- Turn on your furnace: Once the new 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 cease working or decrease its lifespan. Changing your furnace or AC filter is one of the best things you can do to keep your system operating effectively.
