Picking out the right 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, permitting potentially harmful particles to move through your home. It also restricts airflow, which can damage your furnace and reduce its life span.
Ensuring your furnace uses a clean filter that is ideal for your needs is not merely about keeping your furnace operating efficiently. It’s also about creating healthy indoor air quality for your home.
The quality of the air your family breathes is important to the HVAC pros at Street Heating and Cooling. We've long worked with an eye on improving indoor air quality in Rapid City. 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 important to replace dirty air filters in a furnace or air conditioner periodically. 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 examining your furnace filter monthly and replacing it if it’s dirty. You’ll know if it is dirty because it will coated with dirt or dust. Homeowners who have pets will probably want to replace their furnace air filter more often, because an effective 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 commonly installed in the return air duct or blower compartment before the return air reaches the furnace. This makes sure air flowing 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 positioned on the right, left, bottom or in some cases, on the inside of the furnace. It's generally housed within a slot, frame or cabinet for easy access and replacement. Always refer to your furnace's owner manual for important information concerning filter location of your particular brand and model of furnace.
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 the same. While people might refer to them differently 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 particulates 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 a MERV Rating and What MERV Rating Do I Need?
Once you locate your old furnace filter and decide when it should be changed, it’s time to choose a replacement. That means deciding on 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 molecules. The rating scale ranges from 1 to 20, with bigger numbers indicating enhanced capabilities 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 needlessly restricting airflow. However, people with certain health conditions might need a 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 the proper way is crucial for the efficient operation of the unit. Air filters are supposed to face a particular direction, indicated by an arrow printed on the side of the filter frame. The filter should be put in with this arrow pointing toward the furnace or air conditioner, which is the direction of the airflow. If you're unsure about the airflow direction, it may be helpful to remember that air always moves from the return duct to the heat or cooling source. Therefore, be sure that the arrow points at the furnace or air conditioner.
Many people struggle with which direction to point their system's air filter. To help remember, consider taking a picture with your cellular 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 great time to ask about this is during a routine furnace maintenance appointment.
How to Change a Furnace Air Filter
Changing the filter on your furnace or AC is a quick and easy process. Here is a step-by-step list of how to retreive a dirty air filter and exchange it for a new one:
- 1. Turn off your furnace: Make a point to switch off your furnace before starting the process.
- Look for the furnace filter: Typically, the filter is located inside the furnace or in the air return vent. Make a mental note or write down which direction the arrow points on the filter, because you’ll want the arrow on the new filter to point similarly.
- Remove the old filter: Be careful 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 make it easier to keep track of when it's time for another replacement.
- 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 nicely and close any latches or clips that hold it in the compartment.
- Turn on your furnace: Once the replacement filter is completely installed, you can turn your furnace back on.
Will a Dirty Air Filter Cause a Furnace Not to Work?
The simple answer is, yes, a dirty air filter can cause a furnace to cease working or limit its lifespan. Changing your furnace or AC filter is one of the easiest things you can do to keep your system working effectively.