High Efficiency Filters Are Here To Stay.

Since the beginning of the pandemic installing higher efficient filters has been on everyone’s must-do list as they are better at capturing smaller particles.

ASHRAE (American Society of Heating, Refrigeration and Air-Conditioning Engineers) stated that they recommend using “combinations of filters and air cleaners that achieve MERV 13 or better levels of performance for air recirculated by HVAC systems.”

Since they made this statement a MERV 13 rating became the overnight standard for your basic HVAC filter. Replacing the MERV 8 standard rating which has been in effect since the MERV rating began in 1999.

But will this new standard last as we have now come out of the COVID-19 pandemic? That is the question we’ve been asked by our clients and friends. And according to ASHRAE, there has been no indication of change and it looks like higher efficient filters are here to stay.

High-Efficient Filters

The term efficiency in air filters can relate to energy efficiency and/or particle efficiency. In short, the filter is either good at capturing particles or good at being energy efficient. And there are a few types of filters that can be efficient at both, but for the majority, high-efficiency filters are considered filters that are efficient at capturing smaller particles. Because of this, you can expect energy costs to increase due to the higher restriction with higher MERV-rated filters.

High-efficient filters have been known traditionally as your 2nd stage or final filters. They were never designed to have in your home or standard package unit and typically range anywhere from 6” to 12” in depth. They are designed for large Air Handling Units used in large commercial buildings, schools, hospitals, clean rooms, and research labs. Applications like this require a high-efficiency filter as they can capture 75% - 95% of particles across all 3 size ranges.

Technically speaking though, a high-efficiency filter can begin at a MERV 11 but we do not consider these as high efficiencies. As you can see in the chart below (Table 3), MERV 11 is the first MERV rating that has any percentage of capturing particles in the smallest micron range. But that percentage sits only at 20%.

One of the main reasons ASHRAE is recommending at least a MERV 13 filter is that it can be found in almost all filter types and can be used in a wide range of applications. Another reason for having MERV 13 or higher rated filters in your units is because of how COVID-19 and other diseases travel through the air. The COVID-19 virus attaches itself to droplets and droplet nuclei that are predominantly 1-4 microns in size.

So really, starting at a MERV 13 just gives us more opportunity to have a filter in our everyday units that have an 85% - 90% at capturing how COVID travels and a 50% capture efficiency at the smallest micron range.

And as you can see from the chart (Table 3), MERV 13 filters are 85% efficient at removing particulates from the air in that 1.0 - 3.0-micron range and 90% efficient in the 3.0 - 10 micron range.

And a MERV 14 is 90% efficient at capturing particles in the 1.0 - 3.0-micron range. So the higher the MERV rating, the more efficient it is at removing particles in that particle range.

Can your unit handle high-efficient filters?

So with ASHRAE’s recommendation to use MERV 13 or higher filters, we have to be careful not to order and put in the highest-rated filter we can in your units. HVAC units are specifically designed with specific filters in mind. They account for the pressure drop that the filters will carry with them to fine-tune the motor speed.

So putting a higher MERV-rated filter in a package unit that it’s not designed for will increase the chances of overworking the motor as it’s trying its hardest to pull air through a more tightly-woven media. So just be cautious and pay attention to your unit when putting higher MERV-rated filters in.

What type of high-efficient filter is right for your facility?

So now that higher efficiency filters are here to stay what options do you have? When looking at the different types of high-efficiency filters you have several MERV ratings, sizes, and types of filters you can choose from.

High Capacity Pleated Filters

• 1”, 2” and 4” Depth

• MERV 12, 13

• Synthetic Media

• .24 Beverage Board

• Light Weight

High Capacity Minipleat Filters

• 2”, and 4” Depth

• MERV 14A/15

• Synthetic Media

• .24 Beverage Board

• Low Resistance to Airflow

• Light Weight

• High Dust Holding Capacity

Syntetic F-Cell Filter.

• 4”, and 12” depth

• MERV 11, 14, 15

• Synthetic Media

• Plastic Frame

• Low Resistance to Airflow

• Light Weight

• High Dust Holding Capacity

High Capacity Bag/Pocket Filters

• 14”, 15”, 18”, 22”, 25”, 33”, and 36” Depth

• MERV 11, 13, and 14, 15

• Synthetic Media

• Low Resistance to Airflow

• Light Weight

• High Dust Holding Capacity

• Long Life

High Capacity V-Bank Filter

• 12” Depth

• MERV 11, 13, 14, 16

• Synthetic or Fiberglass Media

• Low Resistance to Airflow

• High Dust Holding Capacity

• Long Life

High Capacity Rigid Cell Filter

• 6”, and 12” Depth

• MERV 11, 13, 14

• Microglass Media

• 24 Gauge Stell Cell Sides

• Long Life

High Capacity Rigid Pleat Filter

• 6”, and 12” Depth

• MERV 11, 13, 14

• Synthetic or Fiberglass Media

• Low Resistance to Airflow

• Long Life

Having high-efficient filters in your units even after the pandemic is over still has its benefits too. One, you have filters in place that can combat smaller particles including bacteria, fumes, pollen, and viruses for future pandemic prevention. Also, because of the pandemic, raised awareness for respiratory health took a front seat and more and more of our clients have requested higher efficient filters be in their units permanently.

Overall, having the highest-rated MERV filter in your units is best for having the cleanest air possible for your building and the best defense against any airborne bacteria, viruses, etc. If you would like more information on higher efficient filters contact us today.