Choosing the proper 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 part 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 slows 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 delivering good indoor air quality for your residence.
The quality of the air your family breathes is important to the heating professionals 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?
When Should I Replace My Furnace Air Filter?
Experts stress it's vital 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 more energy to force air through the plugged-up filter.
Officials advise inspecting 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 will very likely want to replace their furnace air filter more often, because an effective 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 commonly installed in the return air duct or blower compartment before the return air reaches the furnace. This ensures 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 positioned on the right, left, bottom or in some cases, inside the furnace. It's generally housed within a slot, frame or cabinet for simple access and replacement. Always refer to your furnace's owner manual for important information regarding filter location of your furnace.
Is My Furnace Filter Just a Type of Air Filter?
The easy answer is, yes. In HVAC, a furnace filter and an air filter or air conditioner filter are basically the same thing. While people might refer to them differently based on the current season— hot or cold—they are all filters that clean the air in your HVAC system.
They each get rid of dust, allergens, bacteria and other contaminants from the air that is drawn into the furnace and air conditioning system, ensuring the air distributed throughout your home is clean and safe.
What Are MERV Ratings and What MERV Rating Should I Have?
Once you find your old furnace filter and figure out when it should be substituted for a clean one, 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 indicates the effectiveness of air filters at trapping airborne molecules. The rating scale ranges from 1 to 20, with greater numbers indicating enhanced capabilities to filter tinier particles.
Experts say a filter with a MERV rating between 8 and 13 offers an ideal balance between having adequate indoor air quality without unnecessarily restricting airflow. However, people with specific health conditions may need to use a filter with a higher MERV rating.
How to Place the Air Filter in a Furnace or Air Conditioning System
Installing 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 printed on the side of the filter frame. The filter should be put in with this arrow pointing at the furnace or AC, 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 picture 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 point. A great time to inquire about this is during a routine furnace maintenance visit.
Changing Your Furnace's Air Filter
Replacing the filter on your furnace or air conditioner is a quick and easy process. Here is a step-by-step list of how to retreive a dirty air filter and replace it with a new one:
- Turn off your furnace: Be sure to turn off your furnace before beginning the process.
- Find the furnace filter: Typically, the filter is located within 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 similarly.
- Slide out the old filter: Be mindful not to knock out any dust or dirt.
- Document the date: Write down the date of replacement on the new filter's frame. This will make it easier to keep track of when it's time for the next change.
- 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 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 unit.
- Turn on your furnace: Once the replacement filter is properly secured, you can turn your furnace back on.
Will a Dirty Air Filter Cause Problems for a Furnace?
The shortest answer is, yes, a dirty air filter can cause a furnace to cease working or limit its lifespan. Changing your furnace or AC filter is one of the simplest things you can do to keep your system working correctly.
