Picking out the proper 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 crucial part in keeping its system running safely, efficiently and for a long time.
A clogged furnace filter loses its effectiveness, allowing potentially harmful particles to flow through your home. It also restricts airflow, which can damage your furnace and shorten its life span.
Making certain your furnace uses a clean filter that is suitable for your needs is not just about keeping your furnace operating efficiently. It’s also about delivering excellent indoor air quality for your household.
Your health is important to the HVAC specialists at Precision Mechanical. We've long been dedicated to improving indoor air quality in Rapid City. Here, we’ve answered common questions about HVAC filters, including that especially tricky question of what direction do you point a filter in your furnace or air conditioner?
When Should I Replace My Furnace Air Filter?
It is important 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 effort to move air through the plugged-up filter.
Officials suggest 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 probably need 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 normally installed in the return air duct or blower compartment before the return air reaches the furnace. This ensures air being pulled into the system is filtered before it passes through the furnace components and is heated.
Depending on the type of furnace, the filter may be positioned on the right, left, bottom or in some cases, on the inside of the furnace. It's typically housed inside of a slot, frame or cabinet for convenient access and replacement. Always refer to your furnace's owner manual for facts regarding filter location of your particular brand and model of 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 AC filter are essentially 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 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 circulating throughout 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 replaced, it’s time to select a replacement. That means determining the level of filtration that you need. One approach to this is by selecting an appropriate MERV rating for your needs.
MERV stands 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 smaller particles.
Experts say a filter with a MERV rating between 8 and 13 offers an appropriate balance between having healthy indoor air quality without overly restricting airflow. However, people with some health conditions may need a a higher MERV rating.
Where to Insert the Air Filter in a Furnace or AC Unit
Installing an air filter in a furnace or air conditioner correctly is important for the efficient operation of the unit. Air filters have 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 in the direction of the furnace or air conditioner, which is the direction of the airflow. If you're doubtful about the airflow direction, remember that air always moves from the return duct and then to the heat or cooling source. Therefore, make certain the arrow points at the furnace or air conditioner.
Many people struggle with which direction to face their air filter. To help remember, consider taking a quick picture with your cell 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 go. A perfect time to ask about this is during a routine furnace maintenance call.
How to Replace Your Furnace Air Filter
Switching out the filter on your furnace or air conditioner is an easy process. Here is a step-by-step list of how to remove a dirty air filter and swap it for a new one:
- Turn off your furnace: Make sure to shut off your furnace before starting up the process.
- Locate the furnace filter: Typically, the filter is found inside 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 replacement filter to point in the same direction.
- Remove the old filter: Be mindful not to knock out any dust or debris.
- Record the date: Write down the date of replacement on the new filter's frame. This will help you keep track of when it's time for you to change it again.
- Put 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 old filter you are replacing.
- Secure the filter: Make sure the new filter fits correctly and close any latches or clips that secure it in the compartment.
- Turn on your furnace: Once the new filter is properly in place, you can turn your furnace back on.
Will 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 shorten its lifespan. Changing your furnace or AC filter is one of the best things you can do to keep your system operating effectively.
