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 vital 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 reduce its life span.
Making certain 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 delivering healthy indoor air quality for your residence.
The quality of the air your family breathes is important to the HVAC pros at Airmax Long Island. We've long worked with an eye on bettering indoor air quality in Long Island. Here, we’ve answered frequent questions about HVAC filters, including that particularly 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 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 pull air through the plugged-up filter.
Officials recommend checking your furnace filter every month and replacing it if it’s dirty. You’ll know if the filter needs to be changed because it will filled with dirt or dust. People who have pets will very likely want 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 installed in the return air duct or blower compartment before the return air gets to the furnace. This is so 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, on the inside of the furnace. It's generally housed inside of a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for facts regarding filter location of the furnace in your home.
Is a Furnace Filter the Same as an Air Filter?
The easy answer is, yes. In HVAC, a furnace filter and an air filter or air conditioning filter are essentially identical. While they might be called different things based on the current season— warm or chilly months—they are all filters that clean the air in your HVAC system.
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 circulating throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you locate your old furnace filter and figure out when it should be replaced, 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 stands for Minimum Efficiency Reporting Values. The MERV rating measures the effectiveness of air filters at trapping airborne contaminants. The rating scale ranges from 1 to 20, with bigger numbers indicating a greater ability to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having adequate indoor air quality without unnecessarily restricting airflow. However, people with specific health conditions might need to purchase a filters with a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or Air Conditioner
Positioning an air filter in a furnace or air conditioner properly is important for the efficient operation of the system. Air filters have 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 air conditioning unit, 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 and then to the heat or cooling source. Therefore, be sure that the arrow points at the furnace or air conditioning unit.
Many people struggle with which direction to face an air filter. To help remember, consider taking a picture with your cell 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 perfect time to inquire about this is during a scheduled furnace maintenance call.
How to Change a Furnace Air Filter
Replacing the filter on your furnace or AC is a quick and easy process. Here is a step-by-step breakdown of how to take out a dirty air filter and swap it for a new one:
- 1. Turn off your furnace: Make sure to switch off your furnace before starting the process.
- Find the furnace filter: Typically, the filter is found within 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 new 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 changed filters on the new filter's frame. This will help your family keep track of when it's time for you to change it again.
- Slide in 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 securely and close any latches or clips that lock it in the unit.
- Turn on your furnace: Once the replacement 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 stop working or limit its lifespan. Changing your furnace or air conditioning filter is one of the best things you can do to keep your system running effectively.