Selecting the proper 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 crucial part in keeping its system working safely, efficiently and for a long time.
A dirty furnace filter loses its effectiveness, enabling potentially harmful particles to flow through your home. It also slows airflow, which can damage your furnace and decrease its life span.
Making certain your furnace uses a clean filter that is suitable for your needs is not only about keeping your furnace working efficiently. It’s also about creating healthy indoor air quality for your household.
Your health is important to the HVAC professionals at Air Current AC & Heat. We've long been dedicated to bettering indoor air quality in Houston. Here, we’ve answered common questions about HVAC filters, including that particularly 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
Experts stress it's important to replace dirty air filters in a furnace or air conditioner periodically. Soiled filters cause the system to worker harder than it should because it takes extra effort to force air through the plugged-up filter.
Officials advise 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 coated with dirt or dust. Those who have pets that shed will very likely 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 gets to the furnace. This makes sure air entering the system is filtered before it goes through the furnace components and is heated.
Depending on the furnace brand, the filter may be found on the right, left, bottom or in some cases, inside the furnace. It's usually housed in a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information about filter location of your particular brand and model of furnace.
Is a Furnace Filter the Same as an Air Filter?
The straightforward 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— warm or chilly months—they are all filters that clean the air in your residence.
They each eliminate dust, allergens, bacteria and other particulates from the air that is drawn into the furnace and air conditioning system, making certain the air flowing through your home is clean and safe.
What Is the MERV Rating System and What Rating Is Best for Me?
Once you find your old furnace filter and figure out when it should be changed, it’s time to choose a replacement. That means picking the level of filtration that you need. One way to do that is by choosing an appropriate MERV rating for your needs.
MERV is an abbreviation 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 the power to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having adequate indoor air quality without needlessly restricting airflow. However, people with some health conditions could need to use a filter with a higher MERV rating.
How to Place the Air Filter in a Furnace or Air Conditioning System
Installing an air filter in a furnace or air conditioner the proper way is crucial for the efficient operation of the heating or cooling system. Air filters are designed to be installed in a specific direction, indicated by an arrow located 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 towards the heat or cooling source. Therefore, make certain the arrow points in the direction of the furnace or air conditioning unit.
Many people have difficulty remembering which direction to install their system's air filter. To help remember, consider snapping a quick photo 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 be installed. A great time to do this is during a routine furnace maintenance appointment.
Changing Your Furnace's Air Filter
Changing the filter on your furnace or air conditioning system is an easy process. Here is a step-by-step breakdown of how to retreive a dirty air filter and swap it for 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 found 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 replacement filter to point the same way.
- Take out the old filter: Be mindful not to knock out any dust or debris.
- 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 another replacement.
- Insert new filter: Put in the new filter with the arrow pointing at the furnace, which is the direction of airflow and should be the same direction the arrow pointed on your last filter.
- 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 new filter is completely installed, you can turn your furnace back on.
Can a Dirty Air Filter Cause Problems for a Furnace?
The short answer is, yes, a dirty air filter can cause a furnace to quit working or decrease its lifespan. Changing your furnace or air conditioner filter is one of the easiest things you can do to keep your system working efficiently.