Position the airflow arrow so that it points in the direction the air is flowing. In addition to clean air, filters also protect your HVAC system from debris and dirt buildup. The airflow arrow should point towards the furnace/blower motor to collect harmful particles before it reaches the furnace's equipment.
The arrow points in the direction that the air is flowing. It does NOT point toward where it's coming from! It points toward where it's going to! It doesn't matter if the vent is an outlet or a return.
It will decrease the efficiency of the air filter and reduce its durability. In worst-case scenarios, it can also cause a complete system failure.
When installing the air filter in the HVAC unit, ensure the arrow should always point towards the blower. This direction ensures that the air flows through the filter material correctly, thereby effectively trapping the particles.
What if there is no arrow on the air filter? If there's no arrow on your air filter, just make sure the side with the frame (usually the cardboard or metal side) faces the furnace. The flat side of the filter should face the return air duct.
The arrow on your air filter should point towards the blower in your HVAC unit. This ensures that the filter catches particles and debris before they enter the system, protecting the internal components from damage. Air filters are designed with different levels of filtration capabilities.
Position the airflow arrow so that it points in the direction the air is flowing. In addition to clean air, filters also protect your HVAC system from debris and dirt buildup. The airflow arrow should point towards the furnace/blower motor to collect harmful particles before it reaches the furnace's equipment.
Determining the direction of airflow on furnace filters is both simple and crucial. Typically, an arrow on the frame of the filter denotes this orientation, pointing out the proper airflow direction, which should be towards the furnace and away from the return duct to ensure effective heating or cooling.
There's an arrow on the box, and it says to point in the direction of “Air Flow”, but what does that mean? It means the arrow faces the unit, or in other words, facing inside the space you're putting it into. Assuming your unit is outside or in your attic, you want the arrow to face the unit.
The most common problem you will face with a backwards facing filter is simple inefficiency. If your furnace is forced to blow air through the non-porous end of a filter, it will take more energy to do so. The blower will be overworked and you will pay more money for your heating.
Installing an air filter backward can damage your furnace or HVAC system, as the airflow will be decreased dramatically. A backwards filter prevents air from flowing into the furnace, which prevents air from flowing out of the furnace.
Incorrect filter installation or installing the wrong filter can leave your engine open to dirt and debris. When the engine's air intake is not completely covered by a filtering element, extensive damage can occur.
Most filters are printed with an arrow that indicates furnace filter airflow. Place the filter with an arrow pointing toward the furnace, in the direction of airflow. Correct placement is important.
You might wonder about the risks of running your AC without a filter, even temporarily. The simple answer is: not for long. Ideally, your AC should never operate without a filter for more than 6-8 hours. Going beyond this can negatively affect both your system's health and your home's air quality.
How Often Do I Need to Change Out My Air Filter? Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or 3 months. That can change based on where your home is located (ex. dusty, dry climates), if you have any pets, and the age of your system and equipment.