Learn about the two sides of central air systems

It is time for you to replace your air filters if have already lived in your new house for 3 months. However, if can find air filters in different places if you are going to find your air filters in some common spots.

Don’t worry about it! Most of central air heating and cooling systems are equipped with two intake vents so that they can circulate the indoor air and purify the pollutants from the air. The amount of intake vents depends on the size of your house, but as for most residents, the central air system is installed with two air filter-covered intake vents.


Do you know why you can find two air filters in your HVAC system?


The central air system in your house



Your system can be made by 3 air circulation parts when you have an AC system and central furnace, and your system need to be opposed to ductless system.


Air handler


This is a metal box that includes the fan motor, fan, condenser coil, and compressor -the crucial parts of your air system that let warm air in and cool it down before flowing it through your house. It is located on the outside of your home along your exterior wall.



Cooling/Heating Manifold


It is a kind of internal system that heats and cools the air by passing different kinds of hot and cold coils, the temperature will be in the desired range set by the thermostat. The central air part also includes the blower, furnace, and evaporator coils.


Air duct system

There are two things included in your AC air system:


● Air that comes from outside of your house is absorbed into the unit, chilled or heated to the proper temperature, then they can be sent back to the duct system in your house. Which is helpful to keep the temperature of your house in the proper range.



● You return ducts can pull back the indoor air, cooling or heating to a proper temperature, and then the air will back to your home through the duct system. This process is helpful to maintain the proper range of temperature and the circulation of air.


It is important for you to understand the different components of the central air system so that it is better for you to understand the working principle when they are installed in different kinds of places.


How to decide if you need to install two air filters


If your HVAC system is in a space that measures less than 900 square feet, such as a one-bedroom apartment, then you may only need one standard filter. That said, it’s best to have multiple levels of filtration—including a carbon filter—for homes with pets or allergies. In some cases, homeowners end up getting away with using just one large filter. In others, however, a professional installation will require two smaller filters instead.


There are many return ducts in your HVAC system


It is the main reason that your central air system needs to be equipped with two air filters. If you live in a large house or apartment, it is essential for your to install enough return ducts to circulate the air. All of us like the comfortable temperature and the fresh air in the room.


Every vent should be installed with an air filter, even if much more return ducts can help you work out the core issue



Your system has an “air handler” and a “return duct”

Different air filters have a different lifespan, as a result, the frequency of changing air filters in the return duct versus air handlers varies is different, because they have different sizes.

For example, the most common size of return vents has a depth of one inch that is designed to include one-inch air filters. In contrast, our filters have an air filter depth of four or five inches if you find our filters specially designed for the air handler. Air handlers need much more filter material because of the large capacity, so they have to hold and collect much more pollen, dust, and smoke before you are ready to change them.

You have different central air systems and each system has its own air filter

You will find it is common in two-story homes because you can control the temperature easily, which means that you have much more air handler filters and more return vents, at least one return vent in each HVAC system.

The way to find your air filter intake vent

Now you have known the reason why you have two air filters, let’s look at the location.

First, shut off your home’s central heat and air system. For your safety, ask a friend or family member for help. Then search for a small plastic square along with one of your ceiling’s main duct lines—this is where your filter intake vent is located. Don’t forget to wear gloves; vents can be covered in mold or dust particles that irritate skin and damage the lungs. Once you find it, simply press it in gently with a screwdriver.


Replace your air filters


You can enjoy a healthy living condition when you’ve known where you can find the air filter replacement so that you can breathe in the fresh air.


You don’t have to buy the air filters from different local stores if you need many air filters, you just have to find the size of your air filter and the brand of your central air system online, then you can get the quantity and type that you need. It is essential for you to look at these resources if it was your first time buying a dehumidifier.



The FAQ of Air Filter Intake vents

Whether should I install the air filter in the return vents?


Yeah, that’s right. You have to install a proper air filter in the return vent, it helps you to purify the air that circulates in your house. And your central air system can run effectively.


How many air filters should you install in your house?  


Generally, there will be 2 air filters in their intake vents. In some situations, the amount is different because of the square footage of the home and the number of floors. And the number of floors that are supported by the central air system.



Whether you should install an air filter with a layer 1 inch


In some situations, your air handler vents and intake vents have a filter that has a depth of more than one inch. However, some people think that they can use a 1-inch air filter to fit the 2-4 inch air filter slot, but it is improper.


You are recommended to put up some advice from a Houzz forum discussion. When you see a return duct that can contain 2 inches or 4-inch air filter, it will multiply if you use many air filters with 1 inch in order to suit the slot. Give up the equipment. As for the working efficiency when it is working with a central air system, whether they work the same way with air filters with 2 or 4 inches. It is worth thinking about it!


Besides, it will cost much more if you buy this air filter this way. The price will be changeable according to the publication of the price.


The way to clean an AC intake vent.


The intake vent can be kept clean if you can replace the intake vent regularly. You can use a duster, or broom and vacuum attachment to remove the pollutants if they multiply, you can use a pressure washer or a hose to clean up the intake vents when there are large amounts of pollutants in the intake vent.


The way to keep the dust out of your AC intake vent cover. 


Replace your air filters regularly is the best way to keep the dust away from your AC intake vent. It is recommended to replace your air filter every 90 days. There is no dust built up on the cover of the intake vent. You can use a vacuum, duster, or broom to clean up the intake vent when there is much more dust in the intake vent.


Compare your Homes AC intake and vent


Actually, they are also can be called” vents” because they both are the places where the air circulates in your house, your intake vents play the role of “pulling” the air from the room, and your duct vents are “drawing” the conditioned air into the room. We will show the difference between fewer in number and larger in size, you can nearly find it in any room of your house.



Change your air filter now

Air filters remove dust, pollen, and other particulates from your home’s indoor air. If you suffer from allergies or sinus infections, it’s a good idea to change your filter every month or so during peak allergy season (which is usually during spring). Otherwise, change it every 3 months or when it starts to feel clogged.

You can look up different air filters with below and make sure that your air system can work normally, you can refer to each link below and choose an air filter with the proper size.


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