Selecting the correct 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, enabling 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 appropriate for your needs is not only about keeping your furnace working efficiently. It’s also about delivering excellent indoor air quality for your home.
Your health is important to the heating pros at LTS Plumbing & Heating Inc.. We've long worked with an eye on enhancing indoor air quality in Shamokin and Sunbury. Here, we’ve answered frequent questions about HVAC filters, including that very tricky question of what direction do you point a filter in your furnace or air conditioner?
How Often to Replace the Air Filter in a Furnace
It is important to replace dirty air filters in a furnace or air conditioner routinely. Dirt-clogged filters cause the system to worker harder than it should because it takes more energy to force 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 be gray or black from dirt or dust. People who have pets will probably 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 normally found in the return air duct or blower compartment before the return air reaches 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 located on the right, left, bottom or in some cases, within the furnace. It's generally housed inside of a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information regarding filter location of the furnace in your home.
Are Air Filters and Furnace Filters the Same Thing?
The simple answer is, yes. In HVAC, a furnace filter and an air filter or air conditioner filter are basically the same thing. 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 HVAC system.
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 the MERV Rating System and What MERV Rating Do I Need?
Once you locate 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 selecting an appropriate MERV rating for your needs.
MERV stands for Minimum Efficiency Reporting Values. The MERV rating calculates the effectiveness of air filters at trapping airborne particles. The rating scale ranges from 1 to 20, with bigger numbers indicating a greater ability to filter smaller 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 some health conditions might need a a higher MERV rating.
Where to Insert the Air Filter in a Furnace or AC Unit
Installing an air filter in a furnace or air conditioner properly is important for the efficient operation of the unit. Air filters have a certain direction, indicated by an arrow written on the side of the filter frame. The filter should be put in 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, remember that air always moves from the return duct and then to the heat or cooling source. Therefore, be sure that the arrow points in the direction of the furnace or AC.
Many people struggle with which direction to point their system's air filter. To help remember, consider taking a quick picture 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 point. A handy time to do this is during a scheduled furnace maintenance call.
How to Change a Furnace Air Filter
Replacing the filter on your furnace or air conditioner is a simple process. Here is a step-by-step list of how to retreive a dirty air filter and swap it for a new one:
- Turn off your furnace: Make sure to shut off your furnace before starting up the process.
- Find the furnace filter: Typically, the filter is positioned inside 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.
- Take out the old filter: Be diligent not to knock out any dust or dirt.
- Record the date: Write down the date of replacement on the new filter's frame. This will help your family keep track of when it's time for another replacement.
- Slide 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 the compartment.
- Turn on your furnace: Once the replacement filter is completely secured, you can turn your furnace back on.
Will 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 decrease its lifespan. Changing your furnace or air conditioner filter is one of the simplest things you can do to keep your system working efficiently.