Picking out the ideal furnace filter and changing it when it becomes dirty is as important to your HVAC system as changing the oil is to your car. Each plays a vital function in keeping its system operating safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, permitting potentially harmful particles to circulate through your home. It also restricts airflow, which can damage your furnace and reduce 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 delivering good indoor air quality for your household.
Your health is important to the heating pros at Northern Comfort Inc. We've long been dedicated to improving indoor air quality in Mankato area. Here, we’ve answered common 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 important to replace dirty air filters in a furnace or air conditioner periodically. Soiled filters cause the system to worker harder than it should because it takes more energy to force 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 it is dirty because it will filled with dirt or dust. People who have dogs and cats will probably need 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 installed in the return air duct or blower compartment before the return air gets to the furnace. This is so air entering the system is filtered before it goes through the furnace components and is heated.
Depending on the furnace brand, the filter may be located on the right, left, bottom or in some cases, on the inside of the furnace. It's generally housed in a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for details concerning filter location of the furnace in your home.
Is My Furnace Filter Just a Type of Air Filter?
The easy answer is, yes. In HVAC, a furnace filter and an air filter or AC filter are essentially the same thing. 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 residence.
They each get rid of dust, allergens, bacteria and other particulates 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 Should I Have?
Once you find your old furnace filter and determine when it should be changed, it’s time to pick 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 indicates the effectiveness of air filters at trapping airborne particles. 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 ideal balance between having adequate indoor air quality without unnecessarily restricting airflow. However, people with specific health conditions might need to use a filter with a higher MERV rating.
Where to Insert the Air Filter in a Furnace or Air Conditioning System
Installing an air filter in a furnace or air conditioner properly is important for the efficient operation of the heating or cooling system. Air filters are designed to be installed in a particular direction, indicated by an arrow located on the side of the filter frame. The filter should be put in with this arrow pointing in the direction of the furnace or air conditioning unit, which is the direction of the airflow. If you're unsure about the airflow direction, remember that air always moves from the return duct and then to 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 install their air filter. To help remember, consider snapping a quick photo with your cellular phone after the filter has been accurately 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 routine furnace maintenance appointment.
How to Replace Your Furnace Air Filter
Replacing the filter on your furnace or air conditioning system is a quick and easy process. Here is a step-by-step list of how to retreive a dirty air filter and replace it with a new one:
- Turn off your furnace: Be sure to switch off your furnace before beginning the process.
- Locate the furnace filter: Typically, the filter is located in the furnace or in the air return vent. Take note of which direction the arrow points on the filter, because you’ll want the arrow on the clean filter to point similarly.
- Slide out the old filter: Be mindful not to knock out any dust or particles.
- 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 you to change it again.
- Slide 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 your last filter.
- Secure the filter: Make sure the new filter fits correctly and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the new filter is safely installed, 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 shorten its lifespan. Changing your furnace or air conditioning filter is one of the easiest things you can do to keep your system running effectively.
