Choosing the ideal furnace filter and changing it when it is dirty is as important to your HVAC system as changing the oil is to your car. Each plays a vital part in keeping its system working safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, allowing potentially harmful particles to move through your home. It also limits 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 running efficiently. It’s also about providing excellent indoor air quality for your home.
Your health is important to the heating and cooling pros at 1st Choice Heating & Air Conditioning. We've long focused on bettering indoor air quality in Mission Viejo. 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?
When Should I Replace My Furnace Air Filter?
It's important to replace dirty air filters in a furnace or air conditioner regularly. Dirty filters cause the system to worker harder than it should because it takes more energy to move air through the plugged-up filter.
Officials advise inspecting your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if it is dirty because it will be gray or black from dirt or dust. Those who have pets will very likely need to replace their furnace air filter more often, because a good 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 usually located in the return air duct or blower compartment before the return air goes back into the furnace. This makes sure air being pulled into the system is filtered before it goes through the furnace components and is heated.
Depending on the furnace brand, 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 simple access and replacement. Always refer to your furnace's owner manual for details concerning 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 identical. While people may call them different things based on the current season— summer or winter—they are all filters that clean the air in your residence.
They each remove dust, allergens, bacteria and other airborne debris from the air that is drawn into the furnace and air conditioning system, ensuring the air flowing through your home is clean and safe.
What Is the MERV Rating System and What MERV Rating Do I Need?
Once you find your old furnace filter and figure out when it should be changed, it’s time to choose a replacement. That means deciding on the level of filtration that you need. One way to do that is by selecting an appropriate MERV rating for your needs.
MERV is short for Minimum Efficiency Reporting Values. The MERV rating measures the effectiveness of air filters at trapping airborne particles. The rating scale ranges from 1 to 20, with bigger numbers indicating enhanced capabilities to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having healthy indoor air quality without overly restricting airflow. However, people with certain health conditions may need a a higher MERV rating.
Where to Insert the Air Filter in a Furnace or Air Conditioner
Installing 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 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 installed with this arrow pointing toward the furnace or air conditioning unit, which is the direction of the airflow. If you're doubtful 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 in the direction of the furnace or air conditioning unit.
Many people struggle with which direction to point an air filter. To help remember, consider snapping a quick photo with your mobile phone after the filter has been properly 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 go. A great time to inquire about this is during a scheduled furnace maintenance visit.
How to Change a Furnace Air Filter
Replacing the filter on your furnace or AC is an easy process. Here is a step-by-step breakdown of how to retreive a dirty air filter and replace it with a new one:
- Turn off your furnace: Make sure to turn off your furnace before beginning the process.
- Find the furnace filter: Typically, the filter is found in 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 replacement 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 help you keep track of when it's time for the next change.
- Insert 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 your last filter.
- Secure the filter: Make sure the new filter fits nicely and close any latches or clips that lock it in the unit.
- Turn on your furnace: Once the clean filter is completely installed, you can turn your furnace back on.
Can a Dirty Air Filter Cause a Furnace Not to Work?
The shortest answer is, yes, a dirty air filter can cause a furnace to cease working or reduce its lifespan. Changing your furnace or air conditioning filter is one of the easiest things you can do to keep your system working efficiently.