Selecting 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 crucial part in keeping its system running safely, efficiently and for a long time.
A dirty furnace filter loses its effectiveness, permitting potentially harmful particles to flow through your home. It also restricts airflow, which can damage your furnace and reduce its life span.
Making certain your furnace uses a clean filter that is appropriate for your needs is not just about keeping your furnace operating efficiently. It’s also about delivering healthy indoor air quality for your residence.
The quality of the air your family breathes is important to the heating and cooling pros at Ilten's. We've long worked with an eye on bettering indoor air quality in Cedar Rapids. 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 Should I Replace My Furnace Air Filter?
It's vital to replace dirty air filters in a furnace or air conditioner routinely. Dirty filters cause the system to worker harder than it should because it takes extra work to move air through the plugged-up filter.
Officials suggest examining 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. 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.
How to Find the Furnace's Air Filter
In general, a furnace air filter is usually installed in the return air duct or blower compartment before the return air reaches the furnace. This is so air entering 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 typically housed within a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for information regarding filter location of your furnace.
Is a Furnace Filter the Same as an Air Filter?
The easy answer is, yes. In HVAC, a furnace filter and an air filter or AC filter are effectively the same. 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 residence.
They each get rid of dust, allergens, bacteria and other contaminants 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 Rating Is Best for Me?
Once you find your old furnace filter and determine when it should be replaced, it’s time to pick a replacement. That means determining the level of filtration that you need. One way to do that is by selecting 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 contaminants. The rating scale ranges from 1 to 20, with bigger numbers indicating a greater ability to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having healthy indoor air quality without needlessly restricting airflow. However, people with specific health conditions could need to purchase a filters with a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or Air Conditioner
Installing an air filter in a furnace or air conditioner correctly is crucial for the efficient operation of the system. Air filters are designed to be installed in a certain direction, indicated by an arrow located on the side of the filter frame. The filter should be installed with this arrow pointing in the direction of the furnace or air conditioner, 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 and then to the heat or cooling source. Therefore, make certain the arrow points at the furnace or AC.
Many people have difficulty remembering which direction to face 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 handy 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 AC is a quick and easy process. Here is a step-by-step breakdown of how to remove a dirty air filter and swap it for a new one:
- Turn off your furnace: Make sure to switch off your furnace before starting up the process.
- Find the furnace filter: Typically, the filter is found within 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 the same way.
- Slide out the old filter: Be careful not to knock out any dust or dirt.
- Record the date: Write down the date you replaced the filter on the new filter's frame. This will make it easier to 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 the old filter you are replacing.
- 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 replacement filter is safely installed, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The shortest answer is, yes, a dirty air filter can cause a furnace to stop working or shorten its lifespan. Changing your furnace or air conditioning filter is one of the simplest things you can do to keep your system running efficiently.