What Are the Differences Between MERV Ratings?

Do you know how to tell the efficiency of an HVAC air filter? The easiest way to tell is by its MERV rating. That's why you need to understand what MERV is and what the differences are between the different ratings.

What Is MERV?

The MERV acronym stands for Minimum Efficiency Reporting Value. It measures how efficient an air filter is at removing airborne particulates. It's a scale that runs from 1 to 16, with 1 being the least efficient and 16 the most. This scale was developed by ASHRAE to give consumers a way to compare air filters for efficiency. Let's look at the difference between different MERV ratings.

MERV 1-4

Filters with MERV ratings between 1 and 4 offer the least air filtration. They are good for keeping dust from getting inside the heating or cooling system. This dust can damage the coils and reduce the efficiency of the entire system. They do capture pollen and dust mites, so they offer minimal improvement in air quality. For the budget-conscious, these are the least expensive.

MERV 5-8

For those who want a bit more air filtration while remaining budget friendly, filters between 5 and 8 MERV are a good choice. They remove mold spores and dust, on top of the pollen and dust mites of the lower rated filters. They also have a price that's still good for the budget.

MERV 9-12

A filter with a MERV rating between 9 and 12 is good for those with mild allergies or breathing ailments like asthma. These filters capture particles like pet dander and auto emissions. According to an HVAC professional, they prevent build-up of dust inside the heating/cooling system. They are more expensive than lower rated filters, however.

MERV 13-16

For the most efficient filters, you need to look at MERV ratings between 13 and 16. They can capture fine particles like bacteria and viruses. These are good choices for anyone with a compromised immune system or severe allergies. They are more expensive, however. You might be thinking that a filter rated MERV 16 is the best choice. Before you go out and by one, however, you need to consider one thing. Can your current system handle it?

Higher rated MERV filters use a fine mesh to capture the tiny particles. This fine mesh makes it harder for air to get through the filter. This air resistance causes the air handler to have to work harder. Older systems may not be able to handle this higher resistance. You need to have an HVAC professional assess the situation.

Call Romano Brothers today. We can advise you on which filter will improve your air quality without stressing your HVAC system.