Picking out the proper 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.
A dirty furnace filter loses its effectiveness, allowing potentially harmful particles to move through your home. It also limits airflow, which can damage your furnace and decrease its life span.
Making sure 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 providing healthy indoor air quality for your home.
The quality of the air your family breathes is important to the HVAC specialists at Morgner Inc. Air Conditioning & Heating. We've long focused on enhancing indoor air quality in Saint Louis. 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 is important 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 work to move air through the plugged-up filter.
Officials recommend checking your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if your filter needs changing because it will coated with dirt or dust. Homeowners who have pets will likely have to replace their furnace air filter more often, because a quality 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 commonly installed in the return air duct or blower compartment before the return air goes back into the furnace. This makes sure air flowing into the system is filtered before it moves 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, 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 details about filter location of your particular brand and model of furnace.
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 air conditioner filter are effectively the same. While they might be called different things based on the current season— summer or winter—they are all filters that clean the air in your home.
They each remove dust, allergens, bacteria and other particulates from the air that is drawn into the furnace and air conditioning system, making certain the air distributed throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you track down your old furnace filter and figure out when it should be substituted for a clean one, it’s time to pick a replacement. That means determining the level of filtration that you need. One method to do this 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 higher numbers indicating a greater ability to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good 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.
Where to Insert the Air Filter in a Furnace or Air Conditioner
Positioning an air filter in a furnace or air conditioner properly is crucial for the efficient operation of the unit. Air filters are designed to be installed in a particular direction, indicated by an arrow printed on the side of the filter frame. The filter should be put in 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, remember that air always moves from the return duct towards the heat or cooling source. Therefore, be sure that the arrow points at the furnace or air conditioner.
Many people are confused by which direction to face an air filter. To help remember, consider taking a picture 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 handy time to do this is during a routine furnace maintenance call.
How to Replace Your Furnace Air Filter
Switching out the filter on your furnace or AC is an easy process. Here is a step-by-step rundown 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 beginning the process.
- Find the furnace filter: Typically, the filter is positioned 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.
- Remove the old filter: Be mindful not to knock out any dust or particles.
- Record the date: Write down the date you changed filters on the new filter's frame. This will make it easier to keep track of when it's time for the next change.
- 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 the dirty filter you just removed.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that hold it in the compartment.
- Turn on your furnace: Once the clean filter is properly in place, you can turn your furnace back on.
Can a Dirty Air Filter Cause Problems for a Furnace?
The shortest answer is, yes, a dirty air filter can cause a furnace to stop working or reduce its lifespan. Changing your furnace or air conditioner filter is one of the simplest things you can do to keep your system operating efficiently.