Picking out the ideal 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 crucial part in keeping its system working safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, allowing potentially harmful particles to move through your home. It also limits airflow, which can damage your furnace and shorten its life span.
Ensuring your furnace uses a clean filter that is ideal for your needs is not only about keeping your furnace working efficiently. It’s also about delivering good indoor air quality for your household.
The quality of the air your family breathes is important to the heating and cooling pros at All Weather Heating & Air Conditioning Inc. We've long worked with an eye on enhancing indoor air quality in Huntsville. 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?
How Often to Replace the Air Filter in a Furnace
It is vital to replace dirty air filters in a furnace or air conditioner routinely. 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 30 days and replacing it if it’s dirty. You’ll know if the filter needs to be changed because it will be gray or black from dirt or dust. People who have dogs and cats will likely need to replace their furnace air filter more often, because a good air filter will trap pet hair circulating in a home.
Locating Your Furnace's Air Filter
In general, a furnace air filter is normally located in the return air duct or blower compartment before the return air goes back into the furnace. This makes sure air flowing into the system is filtered before it moves through the furnace components and is heated.
Depending on the furnace model, the filter may be positioned on the right, left, bottom or in some cases, on the inside of the furnace. It's usually housed inside of 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 furnace.
Are Air Filters and Furnace Filters the Same Thing?
The simple answer is, yes. In HVAC, a furnace filter and an air filter or AC filter are effectively the same thing. 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 home.
They each remove dust, allergens, bacteria and other airborne debris from the air that is drawn into the furnace and air conditioning system, making certain the air distributed throughout your home is clean and safe.
What Are MERV Ratings and What Rating Is Best for Me?
Once you track down your old furnace filter and figure out when it should be replaced, it’s time to choose a replacement. That means deciding on the level of filtration that you need. One approach to this is by choosing 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 contaminants. The rating scale ranges from 1 to 20, with higher 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 AC Unit
Positioning 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 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 not sure 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 air conditioner.
Many people are confused by which direction to install their air filter. To help remember, consider snapping a quick photo with your mobile 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 handy time to inquire about this is during a regular furnace maintenance appointment.
How to Replace Your Furnace Air Filter
Changing the filter on your furnace or AC is a simple process. Here is a step-by-step rundown of how to take out a dirty air filter and swap it for a new one:
- Turn off your furnace: Be sure to turn off your furnace before starting up the process.
- Locate the furnace filter: Typically, the filter is found 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 new filter to point the same way.
- Take out the old filter: Be mindful not to knock out any dust or dirt.
- Note 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 the next change.
- 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 your last filter.
- Secure the filter: Make sure the new filter fits securely and close any latches or clips that secure it in the compartment.
- Turn on your furnace: Once the replacement filter is completely installed, 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 stop working or decrease its lifespan. Changing your furnace or AC filter is one of the best things you can do to keep your system working effectively.