The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHARE) recommends a MERV 6 or higher filter for air conditioners. Most people opt for a MERV 8 filter, which can remove contaminants from MERV 8 to MERV 13. Hospitals usually use MERV 14 to MERV 20. Washable air filters are fabric-based filters that can be washed and reused, but they usually have a MERV rating of 1 to 4, making them unsuitable for environments with high levels of contamination.
A central air conditioner filter is usually made of spun fiberglass or pleated paper or cloth, enclosed in a rectangular cardboard frame. Fiberglass filters, the cheapest, are about an inch thick and are common in older systems. Newer central air conditioning models use thicker pleated filters. We measure how well an air filter removes dust, pollen, and smoke from the air, and we check how freely the air flows through the filter at any fan speed.
When buying a new air conditioning filter, you should take care to select the most suitable one for your air conditioning system. In the summer, when your air conditioner is working really hard, you might want to change it more often. Compared to the cheapest basic filters available, medium-efficiency MERV filters, such as the Nordic Pure MERV 12, can significantly reduce airborne dust, mold spores, pollen, and even smoke. This can help alleviate respiratory conditions according to an NIH study.
HEPA filters are capable of trapping bacteria and tobacco particles from the air due to their high MERV content. A fiberglass filter for heating, ventilation and air conditioning may be right for you if you don't have pets, allergies, or chronic respiratory conditions. However, this means that the heating, ventilation and air conditioning (HVAC) system must work harder to get air through the filter, and not all systems are equipped to do so. A greater amount of air flow can be achieved through such a filter since there is more space for air to pass through. Manufacturers may be exaggerating their concerns about high MERV ratings because recent innovations in air filters allow for high MERV ratings (11 to 1) with a low pressure drop.
The larger surface area has a lower resistance to airflow and makes the filters last longer. How often you use your air conditioner and the type of filter or filters you use will determine how often you should change them. Generally, you should change the cheapest fiberglass filters every 30 days and the higher-quality pleated filters every 60 to 90 days. If less air is passing through your air conditioner's air filters, you'd have to turn up your air conditioner's fan settings a bit to achieve the same effect. When it comes to selecting an air filter for your home's HVAC system, it's important to consider both efficiency and cost. The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) recommends using a MERV 6 or higher filter for residential applications.
Most people opt for a MERV 8, which can remove contaminants from MERV 8 to MERV 13. Washable air filters are fabric-based filters that can be washed and reused but usually have a MERV rating of 1 to 4, making them unsuitable for environments with high levels of contamination. The cheapest option is usually fiberglass filters which are about an inch thick and common in older systems. Newer central AC models use thicker pleated filters which offer better filtration capabilities than fiberglass ones. Medium-efficiency MERV filters, such as Nordic Pure MERV 12 can significantly reduce airborne dust, mold spores, pollen and even smoke which can help alleviate respiratory conditions according to an NIH study. HEPA filters are capable of trapping bacteria and tobacco particles from the air due to their high MERV content but they require more energy from your HVAC system in order to get enough airflow through them.
It's important to consider both efficiency and cost when selecting an air filter for your home's HVAC system.