Choosing the right furnace filter and changing it when it becomes dirty is as important to your HVAC system as changing the oil is to your car. Each plays a critical role in keeping its system running safely, efficiently and for a long time.
An overused furnace filter loses its effectiveness, enabling potentially harmful particles to move through your home. It also slows airflow, which can damage your furnace and reduce its life span.
Making sure your furnace uses a clean filter that is appropriate for your needs is not only about keeping your furnace running efficiently. It’s also about providing good indoor air quality for your residence.
Your health is important to the heating professionals at House of Heating Incorporated. We've long worked with an eye on bettering indoor air quality in Marshfield. 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 periodically. Dirty filters cause the system to worker harder than it should because it takes extra work to force air through the plugged-up filter.
Officials advise inspecting your furnace filter every 30 days 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 dogs and cats will probably need 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 normally installed in the return air duct or blower compartment before the return air goes back into 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 found on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed within 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 AC filter are effectively the same. While people may call them different things based on the current season— warm or chilly months—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, making certain 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 determine when it should be changed, it’s time to select a replacement. That means determining the level of filtration that you need. One approach to this is by choosing an appropriate MERV rating for your needs.
MERV is short 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 the power to filter small 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 to use a filter with a higher MERV rating.
Which Way to Put the Air Filter in a Furnace or Air Conditioner
Putting an air filter in a furnace or air conditioner the proper way is important for the efficient operation of the system. Air filters have a certain direction, indicated by an arrow printed on the side of the filter frame. The filter should be installed with this arrow pointing toward 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, be sure that the arrow points at the furnace or air conditioning unit.
Many people are confused by which direction to point their system's air filter. To help remember, consider taking a picture with your mobile phone after the filter has been correctly 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 perfect time to ask about this is during a routine furnace maintenance visit.
How to Change a Furnace Air Filter
Switching out the filter on your furnace or air conditioning system is an easy process. Here is a step-by-step rundown of how to take out a dirty air filter and replace it with a new one:
- 1. Turn off your furnace: Make a point to shut off your furnace before beginning the process.
- Locate the furnace filter: Typically, the filter is located inside 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 replacement filter to point in the same direction.
- Slide out the old filter: Be diligent not to knock out any dust or particles.
- Record 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 the next change.
- Slide in 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 nicely and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the clean filter is safely in place, 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 quit working or reduce its lifespan. Changing your furnace or AC filter is one of the simplest things you can do to keep your system operating effectively.