In today’s world, the problem of declining air quality is rising at a very fast pace, and this issue is affecting every living organism on the planet Earth. Many reasons are causing this issue, including deforestation, urbanisation, industrialization, climate change, and many other factors. Because of this global crisis, indoor air quality is also affected, and according to the US EPA (United States Environmental Protection Agency), the quality of indoor air is 2 to 5 times lower than the air that is outside. To fix the problem of indoor air, air filters were invented.
An air filter is an important part of an HVAC system, the word HVAC means heating, ventilation, and air conditioner. This system helps to provide proper ventilation and controls the temperature inside a house or building. But the people who want to keep their home’s environment temperature according to them and want clean indoor air must use an air filter. In this blog, the readers will learn everything about an air filter and how it works.
What Is An Air Filter?
An air filter is a type of device that is made of porous or fibrous materials that help it remove airborne pollutants like dust, pollen, mould spores, pet dander, etc. The time when the first air filter was invented isn’t confirmed yet but the first filter was patented in 1848 by Lewis P. Haslett. The first residential air filter was created by two brothers Manfred and Klaus Hammes in 1963 in Germany. In all of these years, air filters have evolved and become efficient at removing airborne particles. Today some filters consist of activated carbon which helps to reduce gaseous substances from the air effectively.
How Does An Air Filter Work?
As mentioned in the above section an air filter helps to clean the air but understanding how it works is very important because this will help individuals to know the importance of an air filter. So here steps that an air filter follows to remove contaminants from indoor air:
Step 1: In the initial stage of air filtration the HVAC system pulls the air with the help of a return air vent and the air travels from the return air duct.
Step 2: An Air filter is situated between the return air duct and the air handler. The filter acts as a medium and the air passes through it according to its efficiency, it will remove contaminants from the air.
Step 3: After the filtration of air it goes inside the HVAC unit components and the unit changes its temperature and blows the air in rooms with the help of a supply air duct and the cycle of air filtration is continuous.
Types Of Air Filters
Air filters come in many varieties and each of them has different abilities and functionalities. To understand what air filter will work the best people should know the filter’s type. So here are 6 best types of air filters that are used by many HVAC users:
1. HEPA Filters
HEPA air filters are the top-ranked filters in the world of air filters because of their extremely high efficiency in capturing airborne contaminants like bacteria, viruses, and other types of microscopic pollutants from the air. The word HEPA stands for high-efficiency particulate air and these filters can remove almost 99.97% of airborne contaminants. These filters are often used in medical facilities like operation rooms, chemical laboratories, and places where a sterile environment is very crucial.
2. Pleated Filters
Pleated air filters are one of the most commonly used filters in residential and commercial areas because of their efficient filtration ability. A pleated filter is made of a small series of pleats of cotton, paper, polyester, and other pliable materials. These filters eliminate airborne particles like pet dander, pollen, dust, and some bacteria. The important feature of a pleated filter is it removes a high amount of contaminants because of the high surface area for filtration.
3. Fiberglass Filters
Fibreglass air filters are one of the most used air filters in households because of many reasons. Reasons like budget-friendly, easy to replace, decent air filtration, and not restricting airflow made a fibreglass filter most commonly used filter air homes. These filters can remove particles like dust and pet dander but not very fine airborne particles. So people who want decent air filtration at a low cost should go for fibreglass filters.
4. Activated Carbon Filters
Activated carbon filters are one of those filters that can easily terminate gaseous substances from the air which includes VOCs (volatile organic compounds), odours, and other harmful gases. These filters are also known as activated charcoal filters because they use charcoal’s activated form that attracts pollutants from the air and adsorbs (sticks on carbon’s surface) them. The best feature about these filters is they can be used with other types of air filters for better air filtration.
5. UV Light Filters
UV light filters are best for eliminating bacteria and viruses from the indoor air. These filters use UV-C light which is short-wave ultraviolet light for the air filtration process. When the contaminants of air pass through a UV light filter they get exposed to the UV lamp that kills the microorganisms by damaging their DNA or RNA. These filters help to prevent illnesses that can be caused by airborne viruses.
6. Washable Filters
Washable air filters are those HVAC filters that are reusable after a wash. These filters have a very long life span of around 5 to 10 years which helps to save money in the long run. Because of its long lifespan, a washable filter is also environmentally friendly. These filters provide decent filtration and only capture large-size airborne particles. It is essential to wash these filters once every 1 or 3 months to keep the air filtration at optimal level.
Benefits Of Air Filters
An air filter can provide many benefits to the HVAC system and its user and these benefits not just have a positive impact on the indoor environment but on the savings of an individual also. So here are 4 main benefits provided by an air filter:
1. Remove Pollutants From Air
An air filter’s main and most important benefit is eliminating airborne pollutants from the indoor air. As mentioned in the above sections when the HVAC system pulls the air the pollutants in the air get captured by the filter while air passes through it. This helps to increase the indoor air quality and creates a healthy environment for the elderly and infants.
2. Protects HVAC System From Damage
Airborne particles like dust, debris, mould spores, etc can be harmful to the HVAC system because these particles enter the system’s components and can cause unnecessary damage. An air filter eliminates large particles as well as small ones and this ensures that the HVAC system will not get damaged by any contaminants of the indoor air.
3. Enhances HVAC’s Temperature Controlling
The HVAC system requires a proper air supply so it can do its work of controlling the air temperature but airborne particles interrupt the air supply. Unclean air makes the HVAC unit inefficient at changing room temperature so an air filter removes the pollutants from the air which provides a clean air supply and this enhances the HVAC’s temperature controlling ability.
4. Increases The Life Of The HVAC System
Airborne particles don’t let the HVAC system work smoothly without any problem because as mentioned earlier particles cause problems to the system’s components. Air filters provide clean air to the HVAC unit and because of clean air, the system works efficiently. A smoothly working system will have a long lifespan because of fewer interruptions to the HVAC components’ work.
Effects Of Dirty Air Filter
Over time air filters get dirty and if this issue isn’t fixed on time the filter will get clogged and it will cause many negative effects. These effects will impact negatively on the HVAC system as well as the user of the system. Here are some of the major effects of a dirty air filter:
1. Increases Electricity Usage
The use of electricity will increase when the air filter is dirty or clogged. A clogged air filter will not let the air pass through it properly and due to that, the HVAC system will force its components to maintain a proper air supply. When the components work more they consume more electricity and because of this individuals can see a rise in their energy bills.
2. Temperature-Controlling Time Increases
A dirty air filter affects the HVAC system’s temperature-controlling time because of improper airflow. Clogged air filters restrict the airflow and due to that HVAC unit can’t get a proper air supply to control the temperature of the indoor environment. The system will take a longer time to change the temperature of a room than usual because the temperature-controlling process becomes slow.
3. Decreases Indoor Air Quality
One of the biggest side effects of a dirty air filter is that it decreases the indoor air quality. When the HVAC system pulls air for filtration, a clogged filter doesn’t remove any contaminants from the air and it throws back the air which is full of impurities to the home. A dirty air filter will make the indoor space more polluted as compared to the HVAC system that does not have an air filter.
4. Decreases HVAC System’s Life
Usually, HVAC system manufacturers provide a 10-year warranty and some systems can stay up to 10 to 25 years or more. But a dirty air filter makes the HVAC’s components push their limit as a result the system may not stay as long as it should be and due to this people may need to buy a new system which will be very costly.
How To Change An Air Filter?
As mentioned in the above section a dirty air filter causes harm to the HVAC system and the indoor environment so changing the filter is a crucial thing. So here are steps to change an HVAC air filter:
Step 1: The most crucial step before changing the air filter is to turn off the power of the HVAC system and to do that individuals can flip the switch which is situated on the side of the unit.
Step 2: The second step is to locate their filter in the HVAC system. Usually, the air filters are situated between the return air duct and the air handler. Checking the HVAC manual also helps to find the location of the filter.
Step 3: After finding the location of the filter it should be removed carefully because all of the captured pollutants can be released into the if a person drops it. One should remember the arrows on the filters while removing them because it will help to insert new filters properly.
Step 4: The last step is to insert the new air filter in the filter slot. So while placing the filter in the slot make sure that the arrow on the filter’s edge is in the same direction as the previous filter was. After this turn on the HVAC system.
Conclusion
For HVAC systems to work well and to keep clean indoor air, air filters are necessary. Using an effective air filter is more essential than ever because of the decreasing quality of outside air caused by pollution and other environmental issues. By removing impurities from the air, such as mould spores, pet dander, and dust, air filters enhance indoor air quality and shield HVAC systems from harm. Various demands are satisfied by several filter types, including pleated, activated carbon, and HEPA filters. Maintaining your HVAC system’s filters on a regular basis will improve airflow, temperature management, and energy efficiency. Using and caring for air filters prolongs the life of your HVAC system and makes your house safer and healthier.
Frequently Asked Questions
To know an air filter’s filtration efficiency MERV ratings come in handy. The word MERV means minimum efficiency reporting value and it is created by ASHRAE. The ratings range from 1 to 20 and every air filter is rated based on the size of airborne particles it captures. Remember high ratings mean more efficiency.
Your air filter gets dirty easily because of some factors. If your house is filled with dust all the time and you don’t clean it regularly then the dust will decrease the quality of air and it will make the air filter work more. Frequent use of the HVAC system can also make the air filter dirty quickly because the filter will capture airborne particles continuously.
You should use an air filter because it helps to provide clean indoor air to you for breathing. Poor indoor air quality can cause health issues and worse respiratory issues like asthma. Longer exposure to low quality air can be dangerous for the elderly and infants so it is important to improve indoor air quality.
Yes, you can use your HVAC system without an air filter but it is not recommended because airborne particles like dust and mould spores can cause damage to the HVAC system. An air filter removes every type of large particle and it prevents any unnecessary damage. So it is wise to use your HVAC system with an air filter.
Yes, an air filter can cause damage to your HVAC system if it is not replaced on time and regularly. Over time an air filter becomes dirty and clogged and due to this air can’t pass through it properly. Your HVAC system will work harder to maintain proper air supply which will cause it to overheat and damage can occur.
Pleated and fibreglass air filters are the best types for residential use because these filters allow balanced airflow and efficiently filter the indoor air. Both pleated and fibreglass filters are affordable for most individuals and support most residential HVAC systems.
Yes, you can use a dirty air filter because it will not stop the HVAC system from working but there are some consequences. A dirty air filter will restrict the airflow and due to that HVAC system will force its components to work more, increase the electricity bill, and may cause damage to the HVAC unit.
