Can Some Types of HVAC Filters Damage Your System?

The air filter prevents particles like dust from ruining the interior components of your heating and cooling system — but only if you put in the right one. The wrong filter will damage the very system it's supposed to protect. Astonishing, isn't it? If you don't want to have an air filter damage your HVAC system, you'll need to avoid these two types of filters:

Wrong High-Efficiency Filter

MERV, or the Minimum Efficiency Reporting Value, expresses how well a filter traps small airborne particles. A higher MERV number represents greater effectiveness at catching small particles.

To improve indoor air quality, some homeowners buy the most powerful HVAC filter they can get. Getting a good filter isn't about buying the highest-efficiency model you can afford. A filter with a higher MERV rating has a tighter weave on it than one with a lower rating. Consequently, the higher-efficiency filter places more resistance against airflow.

Your HVAC system may not have the capacity to accommodate filters with a MERV rating above 12, which could put you at risk for filter damage. The airflow blockage by a high-efficiency filter increases the air pressure in your HVAC system. That could damage your ductwork and even your furnace or air conditioner.

Take care to not replace your filter with a high-efficiency model that your HVAC system can't handle. If you really want clean air, you could install an air cleaner in your ducts. Air cleaners capture small airborne particles without restricting airflow.

Dirty Filter

An air filter will accumulate excessive dirt if you leave it in the return duct for very long. A clogged filter slows down airflow through your HVAC system. With a clogged filter, the system works harder to keep your house warm or cool, which could accelerate wear and tear and increase the need for HVAC repairs.

Check your air filter every month and replace it if it looks dirty.

Always ensure you have an air filter that does its filtration job without causing filter damage that harms your HVAC system. If you need more information on avoiding air filter damage, contact us at Air Assurance. We offer a variety of heating, cooling, and air-quality products to homeowners in the Broken Arrow area.

What Do Those Air Filter Ratings Other Than MERV Mean?

The heating/cooling (HVAC) system in your Tulsa-area home requires relatively little maintenance, but this maintenance needs to be provided on a regular basis. Besides annual check-ups from a qualified HVAC technician, the most important aspect of an efficiently running heating/cooling system is the proper selection and regular replacement of your equipments' air filters. Choosing appropriate filters according to universally accepted air filter ratings such as MERV is where you should start.

Air filters generally carry MERV ratings, a widely accepted rating system developed by ASHRE, the American Society of Heating, Refrigerating and Air Conditioning Engineers. The acronym MERV stands for Minimum Efficiency Reporting Value. The rating numbers, which extend from 1-16 for residential air filters, apply to the particle size a specific filter is capable of trapping. MERV 1-4 filters can capture particles that are 10 microns or larger in size. Filters rated between 5-13 capture increasingly smaller particulate down to as tiny as 1.0 micron. Most experts recommend homeowners use air filters with ratings of from MERV 8-12 for the best balance of economy and efficiency. Anything higher than a MERV-12 will certainly be more aggressive in its filtering capabilities but may also restrict airflow to a point that could be harmful to your equipment.

Some air filter sales outlets have started using alternative air filter ratings other than MERV. These are not approved by ASHRE and may cause some confusion when you're trying to compare efficiency and cost of different filters. Home Depot is one example of a company that's switched from MERV to something called FPR, which stands for Air Filter Performance Rating. An FPR-8, however, is not equal to a MERV-8. MPR, or Microparticle Performance Rating, is another arbitrary rating system used by a certain filter manufacturer. Neither FPR nor MPR are recognized by ASHRE, whose MERV system has been universally recognized and used for decades.

As the largest full-service HVAC equipment and service provider in the Tulsa area, Air Assurance has been providing excellence to our clients since 1985. Contact us for more info or advice on air filter ratings or any indoor air topics.

Our goal is to help educate our customers in the Tulsa and Broken Arrow, Oklahoma area about energy and home comfort issues (specific to HVAC systems). 

Image courtesy of Shutterstock