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 vital function in keeping its system working safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, permitting potentially harmful particles to flow through your home. It also limits airflow, which can damage your furnace and reduce its life span.
Making certain 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 creating healthy indoor air quality for your residence.
The health of your family is important to the HVAC pros at JW Brager Heating and Cooling. We've long been dedicated to bettering indoor air quality in Mount Horeb. Here, we’ve answered common 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?
Experts stress it's important to replace dirty air filters in a furnace or air conditioner regularly. 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 inspecting your furnace filter monthly and replacing it if it’s dirty. You’ll know if your filter needs changing because it will coated with dirt or dust. People who have dogs and cats will probably need 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 normally installed in the return air duct or blower compartment before the return air gets to the furnace. This ensures air being pulled into the system is filtered before it passes 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, within 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 regarding filter location of your particular brand and model of furnace.
Are Air Filters and Furnace Filters the Same Thing?
The simple answer is, yes. In HVAC, a furnace filter and an air filter or AC filter are basically the same thing. 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, ensuring 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 figure out when it should be substituted for a clean one, it’s time to select a replacement. That means determining the level of filtration that you need. One way to do that is by choosing an appropriate MERV rating for your needs.
MERV is an abbreviation 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 the power to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having good indoor air quality without overly restricting airflow. However, people with some health conditions could need to use a filter with a higher MERV rating.
How to Place the Air Filter in a Furnace or Air Conditioning System
Positioning 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 particular 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 at the furnace or AC, which is the direction of the airflow. If you're doubtful about the airflow direction, try to remember that air always moves from the return duct to the heat or cooling source. Therefore, make certain the arrow points at the furnace or air conditioner.
Many people are confused by which direction to point an 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 point. A handy time to do this is during a scheduled 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 list of how to remove a dirty air filter and replace it with a new one:
- Turn off your furnace: Make sure to turn off your furnace before starting the process.
- Look for the furnace filter: Typically, the filter is found within 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 clean filter to point the same way.
- Remove the old filter: Be careful not to knock out any dust or particles.
- Note 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 another replacement.
- 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 old filter you are replacing.
- Secure the filter: Make sure the new filter fits correctly and close any latches or clips that secure it in place.
- Turn on your furnace: Once the clean filter is properly installed, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The short answer is, yes, a dirty air filter can cause a furnace to cease working or limit its lifespan. Changing your furnace or air conditioner filter is one of the simplest things you can do to keep your system working correctly.