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Picking out the correct 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 function in keeping its system running safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, permitting potentially harmful particles to flow through your home. It also restricts airflow, which can damage your furnace and decrease its life span.
Ensuring your furnace uses a clean filter that is suitable for your needs is not merely about keeping your furnace operating efficiently. It’s also about delivering healthy indoor air quality for your household.
The quality of the air your family breathes is important to the heating specialists at Classic Air. We've long focused on bettering indoor air quality in Columbus. Here, we’ve answered frequent questions about HVAC filters, including that especially 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 vital 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 extra effort to force air through the plugged-up filter.
Officials recommend checking your furnace filter every month and replacing it if it’s dirty. You’ll know if your filter needs changing because it will coated with dirt or dust. People who have pets that shed will very likely want 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 gets to the furnace. This makes sure air entering the system is filtered before it moves 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, within the furnace. It's generally housed in a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for information regarding filter location of your particular brand and model of furnace.
Is My Furnace Filter Just a Type of Air Filter?
The straightforward answer is, yes. In HVAC, a furnace filter and an air filter or air conditioner filter are basically the same thing. While they might be called different things based on the current season— warm or chilly months—they are all filters that clean the air in your residence.
They each get rid of dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, making sure the air distributed throughout your home is clean and safe.
What Are MERV Ratings and What Rating Is Best for Me?
Once you locate your old furnace filter and figure out when it should be replaced, it’s time to pick a replacement. That means picking the level of filtration that you need. One approach to 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 molecules. The rating scale ranges from 1 to 20, with bigger numbers indicating enhanced capabilities to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having adequate indoor air quality without unnecessarily restricting airflow. However, people with some health conditions may need to use a filter with a higher MERV rating.
Where to Insert the Air Filter in a Furnace or Air Conditioner
Positioning an air filter in a furnace or air conditioner correctly is necessary for the efficient operation of the heating or cooling system. Air filters have a specific direction, indicated by an arrow written on the side of the filter frame. The filter should be installed with this arrow pointing in the direction of 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 to the heat or cooling source. Therefore, make certain the arrow points at the furnace or air conditioning unit.
Many people have difficulty remembering which direction to point their system's air filter. To help remember, consider taking a picture with your cell 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 go. A perfect time to ask about this is during a regular furnace maintenance appointment.
How to Replace Your Furnace Air Filter
Replacing 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 sure to shut off your furnace before beginning the process.
- Find the furnace filter: Typically, the filter is located in 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 clean filter to point the same way.
- Remove the old filter: Be mindful not to knock out any dust or dirt.
- Record the date: Write down the date you replaced the filter on the new filter's frame. This will help your family keep track of when it's time for another replacement.
- Insert 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 dirty filter you just removed.
- 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 clean filter is safely in place, you can turn your furnace back on.
Can a Dirty Air Filter Cause Problems for a Furnace?
The simple answer is, yes, a dirty air filter can cause a furnace to quit working or limit its lifespan. Changing your furnace or AC filter is one of the easiest things you can do to keep your system operating efficiently.