Selecting the correct 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 critical role in keeping its system operating safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, enabling potentially harmful particles to circulate through your home. It also restricts airflow, which can damage your furnace and shorten its life span.
Ensuring your furnace uses a clean filter that is suitable for your needs is not merely about keeping your furnace operating efficiently. It’s also about delivering excellent indoor air quality for your residence.
The quality of the air your family breathes is important to the heating professionals at County Line Mechanical LLC. We've long focused on bettering indoor air quality in Reinholds. Here, we’ve answered common questions about HVAC filters, including that very tricky question of what direction do you point a filter in your furnace or air conditioner?
When to Replace the Air Filter in Your Furnace
It is vital to replace dirty air filters in a furnace or air conditioner regularly. Dirt-clogged filters cause the system to worker harder than it should because it takes extra effort to force air through the plugged-up filter.
Officials recommend inspecting your furnace filter every month 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 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 normally found 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 furnace model, the filter may be found on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed inside of a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for important information about 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 air conditioning filter are effectively the same. While people may call them different things based on the current season— hot or cold—they are all filters that clean the air in your home.
They each eliminate dust, allergens, bacteria and other particulates from the air that is drawn into the furnace and air conditioning system, making sure the air flowing through your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you find your old furnace filter and determine when it should be substituted for a clean one, it’s time to pick a replacement. That means picking the level of filtration that you need. One method to do this is by picking 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 molecules. 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 a good balance between having adequate indoor air quality without needlessly restricting airflow. However, people with certain health conditions could need a a higher MERV rating.
How to Place the Air Filter in a Furnace or AC Unit
Positioning an air filter in a furnace or air conditioner properly is crucial for the efficient operation of the system. Air filters are designed to be installed in a specific direction, indicated by an arrow written on the side of the filter frame. The filter should be placed in the unit with this arrow pointing at the furnace or air conditioner, which is the direction of the airflow. If you're not sure about the airflow direction, try to remember that air always moves from the return duct and then to the heat or cooling source. Therefore, make sure the arrow points in the direction of the furnace or air conditioning unit.
Many people have difficulty remembering which direction to point their air filter. To help remember, consider taking a picture with your cell 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 perfect time to do this is during a regular furnace maintenance visit.
Changing Your Furnace's Air Filter
Changing 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 take out a dirty air filter and replace it with a new one:
- Turn off your furnace: Make a point to shut off your furnace before beginning the process.
- Look for the furnace filter: Typically, the filter is positioned 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 new filter to point in the same direction.
- Slide out the old filter: Be diligent not to knock out any dust or particles.
- 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 the next change.
- Put 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 the old filter you are replacing.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that lock it in place.
- Turn on your furnace: Once the replacement filter is safely installed, you can turn your furnace back on.
Can a Dirty Air Filter Damage My Furnace?
The short 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 best things you can do to keep your system running correctly.