Why Does My Central Air System Have Two Filters?

The temperature of today’s world is increasing day by day, and humans spend most of their time indoors, like in homes, offices, schools, etc., but the indoor conditions are not good either. The solution to this problem is a central air conditioning system, which helps control the temperature of your entire house or building. It also purifies the air with the help of an air filter, but do you know that some systems have two air filters? If your answer is yes and you also have a central air unit with two air filters and want to know why it has more than one filter, then you came to the right place.

Reasons like having multiple return air ducts, the presence of an air handler with two filter slots, etc. can cause your central air conditioning system to have two filters. If you don’t understand these terms, like return air ducts and air handlers, then don’t worry; in this blog, you are about to learn everything related to central air conditioning systems, so read carefully till the end.

What Is Central Air Conditioning System?

The central air conditioning system, also known as central AC (air conditioner) helps to control the temperature of the air, whether it's cooling or heating, in a central location and is distributed to all locations in a home or building, such as multiple rooms or workplaces. It is not like a single AC unit that only controls one room's temperature at a time. In a lot of central AC, the air temperature is controlled in the AHU (air handling unit), which consists of two things: heating and cooling coils. There are two types of central air conditioning systems and they are:

Types Of Central Air Conditioning System

The central air conditioning system has two types. Both of them have different types of functions. Here they are:

• Split-system: This system consists of two main components: an outdoor and an indoor cabinet. The outdoor cabinet consists of a condenser, fan, and compressor. The indoor cabinet contains an evaporator, but many split systems contain a furnace and an air handler too. The evaporator coil of the conditioner is installed in the supply duct of the heat pump in your home. Individuals who have a furnace but don’t have AC should use a split system because it is a budget-friendly solution for them.
• Packaged system: This type of central air conditioning system contains all of its components, such as the evaporator coil, condenser coil, and compressor, in one cabinet, and these are mostly located on a slab of concrete next to your house’s foundation or on the roof of your home. This type of system mostly includes a natural gas furnace or an electric heating coil.

How Does Central Air Conditioning System Work?

The central air conditioning system in your home takes many steps to control the temperature of your house. First, the role is conducted by a central control instrument called a thermostat. The process starts when this instrument detects the temperature of the air, decides whether it needs to be cool or not, and sends a signal to the AC system’s components, which are inside and outside. Through return air ducts, a fan that is situated in the inside unit pulls all the hot air inside your home. 

The air passes through a filter to remove all the dust and dirt. After this, the hot air goes from the evaporator coil, where the air temperature is lowered and it becomes cool with the help of chemical refrigerant, then the ductwork sends the chilled air all over the house. A copper tube helps refrigerant gas to go into the compressor, which is part of the central air conditioning system’s outside unit. The gas refrigerant is pressurized by a compressor and then sent to a condenser coil, where it becomes liquid. The liquid refrigerant goes inside the unit with the help of a copper tube, and the cycle continues.

What Is An Air Filter?

An air filter is an important part of your central air system; it is a medium between air and the system from where air passes and airborne particles like dust, dirt, pollen, etc. are captured in it. Air filters are made with different materials, such as fiberglass and activated carbon.

There are many types of filters with various functionalities; here they are:

• HEPA Filters: These filters are also known as high-efficiency particulate air filters and are considered the best filters on the market. They remove 99.97 percent of airborne particles indoors of size equal to 0.3 microns or less. Viruses, bacteria, and other microscopic organisms are filtered efficiently by HEPA filters.
• Pleated Filters: filters that are made with pliable materials like paper, cotton, or polyester are known as pleated filters. The materials are folded into small series of pleats that increase their surface area, which helps in capturing huge amounts of particles like pet dander, pollen, mold spores, etc.
• Fiberglass Filters: Use of these filters indoors is common because of their affordability. It consists of a thin layer of fiberglass that helps to eliminate large particles like dirt, dust, debris, etc. These filters are good choices for those people who want decent air purification in their homes.
• Activated Carbon Filters: These filters are also called activated charcoal filters because the main material used to purify air is charcoal. It adsorbs (captures pollutants on its surface) VOCs, smoke, and chemical fumes. Activated carbon filters are also efficient at removing odors from your home.

Why Does Your Central Air Conditioning System Have Two Filters?

The presence of two air filters can happen due to some circumstances. Houses that are large in size or big buildings most of the time require more than one air filter because a large amount of air is going through the process of cooling. Here are some of the reasons that led to having two central air conditioning system filters:

Multiple Return Ducts

Large houses or buildings will have an impact on the HVAC system’s design, and due to this, the chances of multiple return air ducts (a system that pulls home air) increase. Air conditioners that are 3 tons or more will most of the time have more than one filter grill. A properly designed central air conditioning system consumes the same amount of air that it throws out with the help of vents and registers. The simple rule is that when the number of rooms increases, the requirement of supply vents increases, which needs more amount of return air. The high amount of return air needs more effective filtration, which is not possible with one return air duct, so the system uses more ducts to tackle the filtration issue and requires more than one filter.

Multiple Central Air Conditioning Systems

Houses and buildings with multiple floors sometimes face the issue of not cooling of upper flower. In this situation, the temperature of the upper flower doesn’t properly change compared to the bottom floors. The solution to this problem is to invest in a central air conditioning system for each floor. When the amount of air increases, then the number of filters will too because each floor will require air filtration.

Air Handler Have Two Filter Slots

Some manufacturers add dual filter slots in the air handler, but many HVAC professionals are against using two filters at the same time. The air handler with two filter slots is designed in a way that the first filter will remove large airborne particles and the second will eliminate smaller particles. Sometimes both filters are different; one slot will use a 5-in filter and the other will use a 1-inch filter. This type of air handler can hurt the airflow, which may cause damage to the central air conditioning system in the future.

Components of Central Air conditioning system

Central air conditioning system helps to control the temperature of your entire house or building, but have you ever wondered what components are inside it? These parts help change the temperature of your entire living area according to your requirements. Here are the main components:

The Evaporator Coil

The evaporator coil is one of the important parts of your central air conditioner. The coil is lined with thin aluminum fins. When the air is consumed by your system and sent to the coil, the chemical refrigerant inside the coil absorbs heat to cool air, and then the air handler blows it through the duct. It is recommended to clean the evaporator by an expert during visits for maintenance.

The Condenser Coil

The condenser coil plays an important role in the central air conditioners. The main job of the coil is to release heat from the refrigerant. The fan of the condenser is situated inside the outdoor cabinet that sends outside air through the coil; here the coil uses airflow to eliminate the heat from the refrigerant, which turns hot refrigerant vapor into liquid.

The Compressor

The compressor is also known as the heart of the central AC, and it is important to control your home temperature. It is located alongside the condenser coil in the outdoor cabinet. The purpose of the compressor is to compress the refrigerant vapors into a denser form, which increases the temperature and pressure of the vapor. After this, the vapors are sent to the condenser coil.

The Expansion Valve

This component of the system helps convert the liquid form of refrigerant into vapor again. When the liquid refrigeration passes through an orifice, the pressure decreases, which is put on refrigerant. This reduction in pressure allows the chemical to turn back into cold vapors and go to the evaporator coil, and this process continues.

Ductwork

The central air conditioning system takes the help of ductwork that allows the system to cool your entire home or building. The air handler throws cool air into the central duct, which sends all of the low temperatures to every room in your house. In the air registers, ducts end, and they have grills that can be adjusted to control the flow of air.

Thermostat

Your central air conditioner is controlled by the thermostat. According to the settings of temperature, the thermostat detects the outside temperature and decides when to operate your air conditioner according to your requirements. This instrument is placed in a shaded area so its temperature-sensing ability doesn’t get disrupted.

Benefits Of Central Air 

Controlling your home’s temperature has now become easy with the help of a central air conditioning system. It changes the air to cool or warm according to your requirements and sends it all over the house or building, but the benefits don’t end here. Here are some of the key benefits of a central air conditioning system:

High Comfort Level

A normal single-unit air conditioner only provides its cooling effect to a small area like one room, but this is not the case in a central air conditioning system. This system spreads the cooled air to every corner of your house and room, and due to this, you can enjoy your favorite room temperature in every place in the house. The central air conditioning system is very beneficial for big houses and multi-story buildings.

Improve Indoor Air Quality

A central air conditioner has high-quality air filters that help to eliminate airborne particles like dust, dirt, pet dander, pollen, etc. When the air passes through the filter, all of the contaminants are captured, and this improves the indoor air quality. So it is ideal for those who are allergic to dust or have respiratory issues like asthma.

High Level Of Convenience

Central air conditioners come with an instrument known as a thermostat, which is situated in the center of your house. With the help of this, you can adjust the temperature of your entire house, and this eliminates the requirement of turning on the AC manually from one room to another. There are lots of central air conditioning systems that provide a programable thermostat that allows you to create a personalized cooling schedule according to your requirements.

Create Less Noise

One of the best benefits of a central air conditioning system is that it is quiet when you operate it. Other air conditioners, like portable or window AC, create a lot of noise that can be irritating sometimes. The central air conditioners are designed in a way that they do their work without any noise pollution. Due to this, they are best for places where a peaceful environment is necessary.

Energy Efficient

The central air conditioning system consumes more energy than a single unit AC, but with some measures, they can be energy efficient also. New models of central AC systems are manufactured to limit their energy consumption, and with the help of technologies like programmable thermostats and variable-speed compressors, you can control the energy usage of your system. 

Maintainance Of Your Central Air Conditioning System

Regular maintenance of your central air conditioning system is important, and if you don’t focus on maintaining the system, then over time its efficiency in controlling air temperature will decrease. You can take some measures to keep your system in the best condition, and here they are:

Change The Air Filter

An air filter starts clogging and becomes dirty over time, and this causes airflow restriction. Due to this, your central air conditioning system will work harder to keep the required home environment, and this will cause high energy consumption. It is recommended to change the filter every 1 to 3 months, and it depends on usage and filter manufacturer recommendations. You can clean the filter if you have a reusable or washable filter.

Clean Evaporator Coil

Dust and dirt build inside the evaporator coils over time of your central air conditioner, and this harms the efficiency of cooling the air of the system. Cleaning the evaporator coil regularly is crucial. To clean, you can use soft brushes or buy a specialized coil cleaner and clean the coil very carefully because it is very delicate and vulnerable to excessive force.

Check And Clean The Outdoor Unit

Your system’s outdoor unit is exposed to harmful things like vegetation, dust, and debris. So you should check the surroundings of the unit and remove those things that can cause any harm. It is necessary to cut any overgrown grass that can interfere with the airflow and clean the coils inside the unit with a vacuum cleaner or soft brush.

Clean Condensate Drain Line

The function of the condensate drain line is to tackle and eliminate extra moisture from the central air conditioning system. Things like algae, debris, or mold can clog the line over time, which can cause malfunction of the system or water leaks. To keep drain lines clean regularly, you can use a mixture of water and bleach or invest in a specialized drain line cleaner and use it. So always make sure that the line is working properly.

Schedule Expert Maintenance

A normal individual can do some tasks for maintenance, but it is recommended to schedule expert maintenance once a year. There are many problems that only an expert can see and fix. A professional will check and identify the flaws and repair requirements for your central air conditioning system. With the help of an expert, you can extend the life of your system.

Conclusion

A central air conditioning system helps to control the temperature of an entire house or a building. Unlike other single-unit air conditioners like windows and portable AC, it cools the air in all rooms simultaneously. Many central ACs have two air filters due to reasons like multiple air ducts, two filter slots in the air handler, and multiple central air conditioning systems in one building or house. Maintaining this system is important because carelessness can cause it to become less efficient in its work. A combination of an air filter and a central air conditioner will help you to have a clean environment in your home and office.

This combination will remove airborne particles like dust, dirt, pollen, etc. It also helps individuals who have respiratory issues by removing allergens from the air. If you are wondering where you will get the right filter for your central air conditioning system, then don’t worry; you have come to the right place. Here, at Custom Filter Direct, we provide customized air filters to our customers. What are you waiting for? Contact us at (877) 749-1748 and order your filter today. It will be our pleasure to help you.

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