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Choosing the ideal 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 vital part in keeping its system running safely, efficiently and for a long time.
A dirty furnace filter loses its effectiveness, allowing potentially harmful particles to move through your home. It also limits airflow, which can damage your furnace and reduce 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 providing healthy indoor air quality for your home.
The health of your family is important to the heating and cooling professionals at AC Sales. We've long worked with an eye on enhancing indoor air quality in Lafayette. 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
Experts stress it's critical to replace dirty air filters in a furnace or air conditioner periodically. Dirt-clogged filters cause the system to worker harder than it should because it takes extra effort to move air through the plugged-up filter.
Officials recommend examining your furnace filter monthly and replacing it if it’s dirty. You’ll know if your filter needs changing because it will be gray or black from dirt or dust. People who have dogs and cats will probably 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 normally located in the return air duct or blower compartment before the return air gets to the furnace. This is so air flowing into 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, within the furnace. It's generally housed inside of a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for facts concerning filter location of your furnace.
Is a Furnace Filter the Same as an Air Filter?
The simple 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— hot or cold—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 sure the air flowing through your home is clean and safe.
What Is a MERV Rating and What MERV Rating Do I Need?
Once you find your old furnace filter and decide when it should be substituted for a clean one, it’s time to choose a replacement. That means determining 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 measures the effectiveness of air filters at trapping airborne contaminants. The rating scale ranges from 1 to 20, with bigger numbers indicating enhanced capabilities to filter small particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having good indoor air quality without overly restricting airflow. However, people with certain health conditions might 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 crucial for the efficient operation of the heating or cooling system. Air filters are designed to be installed in a certain direction, indicated by an arrow printed on the side of the filter frame. The filter should be installed with this arrow pointing in the direction of the furnace or AC, which is the direction of the airflow. If you're doubtful about the airflow direction, 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 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 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 be installed. A perfect time to ask about this is during a routine furnace maintenance call.
How to Change a Furnace Air Filter
Switching out the filter on your furnace or AC is a quick and easy process. Here is a step-by-step breakdown of how to take out a dirty air filter and swap it for a new one:
- 1. Turn off your furnace: Be sure to shut off your furnace before beginning the process.
- Look for the furnace filter: Typically, the filter is found in the furnace or in the air return vent. Make note of which direction the arrow points on the filter, because you’ll want the arrow on the new filter to point in the same direction.
- Remove the old filter: Be mindful not to knock out any dust or dirt.
- 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 you to change it again.
- Slide in new filter: Put in the new filter with the arrow pointing in the direction of 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 correctly and close any latches or clips that hold it in the unit.
- Turn on your furnace: Once the new filter is properly secured, 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 cease working or reduce its lifespan. Changing your furnace or AC filter is one of the simplest things you can do to keep your system working effectively.