Furnace Filters vs AC Filters: What’s The Difference?

Have you ever wondered how important it is to breathe clean and fresh air when you are in your home? Whether you're struggling with allergies, dust, dirt, or just want to improve air quality, the use of filters in the HVAC system can be extremely helpful in such cases. The HVAC system’s main function is to collect particles such as dust, debris, pollen, pet dander, and other airborne particles present in the air. The filters are very helpful in enhancing indoor air quality and preventing the circulation of harmful particles within your house and giving you hot and cold air as per your requirements.

However, you will see a lot of people who get confused between furnace filters and AC filters. Do both of these filters mean the same thing? What's the difference, if any? How do you determine which one you actually need? Understanding the difference is important since the quality of your air and the efficiency can be significantly affected by the filter you choose. Understanding the difference is important since the quality of your air and the efficiency can be significantly affected by the filter you choose.

What Is A Furnace Filter?

A furnace filter is a part of the heating system that works by filtering all dust, debris, and other particles from the air before they get to the furnace. This enhances the quality of the air inside your house and also prevents damage to the furnace's interior components. Air can move freely through a clean filter, which makes your furnace function more effectively and consume less energy.

Working Of A Furnace Filter

Here is a brief description of the working of furnace filters :

Step 1: The air that is present in your indoor space is pulled into the furnace through a duct known as the return duct. This duct normally passes through your home's ceiling or baseboard.

Step 2: Now, the air enters the furnace through the return duct and passes through the filters. Usually, this filter is situated near the blower fan.

Step 3: These filters are made up of mesh or fibers, which act as a barrier for particles such as dust, pollen, pet dander, and other airborne particles. These particles are captured in the fibers or mesh filters as the air passes through them.

Step 4: Once the air is filtered, it then enters the furnace's heat exchanger, where the air is heated using a fuel source like natural gas or electricity. After that, the heated air is sent back into the home through the supply ducts, filling your living area with heat.

What Is An AC Filter?

An air conditioning system is used to purify the air that passes through the system. Before the air is cooled and returned to your house, the AC filter performs its main function of collecting dust, pollen, allergies, and other airborne particles present in the air. This improves comfort levels and makes the system function with greater efficiency and increases the equipment's lifespan.

Working Of An AC Filter

Here is a brief description of the working of AC filters:

Step 1: The warm air that is present in your house is pulled into the air conditioning unit through a return duct. This duct is found close to the baseboards or ceiling.

Step 2: The air enters the AC unit through the return duct and passes through the AC filter. Usually, you may find this filter close to the blower fan.

Step 3: Usually the air conditioning systems are made up of mesh or fiber material, which is very helpful in trapping the pollutants that are present in the air. As the air passes through the filter, all these particles are collected.

Step 4: The filtered air now travels through the coils of the evaporator, which uses a refrigerant to cool the air. After that, supply ducts are used to circulate cool air throughout the living space.

Key Differences Between Furnace Filters And AC Filters

The work of both furnace filters and AC filters is to provide clean and fresh air that is free from dust, dirt, pollen, and pet danger. The difference between a furnace filter and an AC filter is as follows:

Furnace Filter

First, let's discuss the furnace filter in detail.

1. Purpose: Furnace filters are designed to clean the air that passes through your furnace, removing contaminants such as dust, pollen, pet dander, and other airborne particles. This helps improve the air you breathe inside your home and also protects the furnace's internal parts from getting clogged or damaged by dirt and debris. By keeping the air and the system clean, the filter ensures better air quality and keeps the furnace running smoothly.

2. Location: Furnace filters are usually located inside the furnace unit itself, near the blower fan. By placing the filter in this manner, impurities may be captured before the air is circulated throughout the house, resulting in cleaner air and furnace protection.

3. Size: Depending on the type of your furnace, there are many sizes available, but in general, furnace filters are smaller than AC filters. To guarantee enough airflow and efficient filtration, it is important that you use the appropriate size filter for the model of your furnace.

4. Filter Material: Furnace filters are usually made up of fiberglass for trapping larger particles and pleated filters are made of cotton or polyester for smaller particles. Some also use electrostatic materials that attract particles, while HEPA filters effectively capture tiny allergens and pollutants.

5. Types: There are usually three types of furnace filters. Pleated paper filters, which are widely used and provide good filtration for most homes; fiberglass filters, which are less expensive but effective at capturing large particles; and HEPA filters, which are extremely effective at capturing the smallest particles and perfect for homes requiring high air quality, particularly for allergy sufferers.

6. Cost: Furnace filter prices vary according to size and type of filter. The cost of Furnace filters ranges from $15 to $25 for a single filter; however, there are many factors to take into account. HEPA filters, which provide better filtration, are usually more expensive as compared to fiberglass filters, which are generally affordable.

AC Filter

Now let's discuss the AC filter in detail.

1. Purpose: The purpose of air conditioner filters is to purify the air that passes through them. The AC’s collect all the impurities, such as dust, pollen, pet hair, and other debris, from the air and help improve the air you breathe. This keeps your air clean and helps the system to operate smoothly.

2. Location: AC filters are usually found inside the external unit of your air conditioner and these are usually placed next to the place from where the air enters the system.

3. Size: Although AC filters come in a variety of sizes, they are usually larger than furnace filters as AC systems can generate higher airflow. When you plan to change your air filter, ensure that you buy the appropriate size filter for your air conditioning device.

4. Filter Material: In AC filters, pleated filters are made of cotton or polyester so that they can more effectively collect small particles, whereas fiberglass is used to capture larger particles. They can also have HEPA filters and electrostatic filters to collect microscopic allergens in the air.

5. Types: There are several types of AC filters. Some of them are pleated paper filters, which are common and are good for home filtration. Pleated air filters are more effective than Fiberglass filters but less effective as compared to HEPA filters. HEPA filters nearly capture all small particles, making them ideal for people with allergies or those who need cleaner air.

6. Cost: Depending on the type, size, and brand, AC filters might have different prices. HEPA filters are more expensive than regular filters as they can very efficiently capture the tiny particles. Costs for pleated or fiberglass air filters vary from $6 to $50 per unit, and they are generally used in the majority of houses as air conditioning systems.

How To Choose The Right Filter For Your Home

There are some important things that should be taken into consideration when choosing the ideal filter for your house, whether you choose an AC filter or a furnace filter.

1. Know Your HVAC System: The first thing that you should do is to know which type of HVAC system you have. The needs for filters differ in each system. You can choose an air filter that fits well with your system and performs the best for your requirements.

2. Analyze Your Needs: You may start by determining the objectives you have for your HVAC system. Whether you want to maintain the air quality, protect your heating system, or perform cooling in your house, select the appropriate filter for your needs that can satisfy all your requirements.

3. Evaluate Filtration Efficiency: Check whether the filter you are thinking about has an effective filtering rate. Check out the rating provided by MERV (Minimum Efficiency Reporting Value). Although HEPA filters are excellent at removing minute particles, to guarantee good air quality without causing problems, select a filter with a MERV rating that matches your system and your needs.

4. Consider Filter Types: Discover the various types of filters that are available. You can choose from pleated filters, which have greater surface area for better performance, electrostatic filters, which use static electricity to catch particles, and fiberglass filters, which are more affordable and can collect bigger particles. Consider HEPA filters for smells, carbon filters for fine particles, and electrostatic filters for improved overall capture when choosing air filters.

Conclusion

Once you are aware of the differences between an air filter and a furnace filter, it will help you to maintain a healthy and comfortable environment in your indoor spaces. As you know, both types of filters contribute to improved air quality by capturing the dust, allergens, and other particles present in the air. Furnace filters protect your heating system and guarantee clean air in your home, while air filters clean the air that your air conditioning system cools. When selecting a filter you should first know about your HVAC system, your requirements for air quality, the filter's effectiveness, and how frequently maintenance is required.

To get detailed knowledge about the types of filters you can get knowledge from our expert team at Custom Filters Direct. We will guide you to know about the best filter which will help you improve the efficiency of your HVAC system, save energy costs, and provide you and your family with better indoor air quality. Contact us today at (877) 556-2862 to get the best advice to choose the best filter as per your needs.

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