Choosing the right 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 function in keeping its system operating 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 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 operating efficiently. It’s also about creating good indoor air quality for your residence.
Your health is important to the HVAC specialists at Enertek Air Conditioning & Heating. We've long been dedicated to bettering indoor air quality in Northridge. 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's 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 advise checking your furnace filter every 30 days and replacing it if it’s dirty. You’ll know if it is dirty because it will coated with dirt or dust. Those who have dogs and cats will very likely have to replace their furnace air filter more often, because a quality 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 located in the return air duct or blower compartment before the return air reaches the furnace. This makes sure air entering the system is filtered before it passes through the furnace components and is heated.
Depending on the furnace model, the filter may be located on the right, left, bottom or in some cases, inside 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 facts about filter location of your 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 effectively the same. 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 home.
They each remove dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, making certain the air circulating throughout your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you track down your old furnace filter and figure out when it should be changed, it’s time to select a replacement. That means picking the level of filtration that you need. One method to do this is by picking 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 particles. The rating scale ranges from 1 to 20, with greater numbers indicating the power to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers a good balance between having good indoor air quality without unnecessarily restricting airflow. However, people with some health conditions could 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 properly is crucial for the efficient operation of the unit. Air filters are designed to be installed in a certain direction, indicated by an arrow located on the side of the filter frame. The filter should be installed with this arrow pointing at the furnace or air conditioner, which is the direction of the airflow. If you're unsure 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 toward the furnace or AC.
Many people struggle with which direction to install their system's air filter. To help remember, consider taking a quick picture with your cell phone after the filter has been accurately 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 great time to inquire about this is during a regular furnace maintenance appointment.
How to Change a Furnace Air Filter
Changing the filter on your furnace or AC is an easy process. Here is a step-by-step breakdown of how to take out a dirty air filter and exchange it for a new one:
- 1. Turn off your furnace: Be sure to turn off your furnace before starting up the process.
- Find the furnace filter: Typically, the filter is positioned in 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.
- Slide out the old filter: Be diligent not to knock out any dust or particles.
- Document the date: Write down the date you changed filters on the new filter's frame. This will help you 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 your last filter.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that secure it in place.
- Turn on your furnace: Once the replacement filter is safely secured, 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 air conditioning filter is one of the simplest things you can do to keep your system running efficiently.
