The Skinny on Filtration

Have you ever changed the filter in your air conditioner? Getting to the thing can be a chore… but then comes the onslaught of options available on the filter aisle at the store. Holy cow! Read along below and I’ll try to make some sense of it all.

Before we get started though, let me introduce you to the American Society of Heating, Refrigeration and Air Conditioning Engineers. These boys sat around the science lab and developed a standardized test for evaluating filters. They call it the MERV. Skipping all the technical mumbo jumbo, it all boils down to a scoring system ranging from 1 to 16, with 1 being the worst and 16 being the cream of the crop.

Okay, now we can move forward. Let’s return to the filter aisle at your local filter store.

First, and worst, we have the one-inch fiberglass throwaway filters. Sure, they’re the cheapest on the store aisle, but there’s a reason: They may protect the HVAC blower compartment from large particles, but they do just about zilch against the smaller stuff, not to mention cleaning the air in your home. On the MERV test, they score a 1 or 2 rating.

Next up are the one-inch pleated media filters. They’re the ones that look like accordion folded paper in a cardboard frame. They score a MERV 5 rating. In short, they protect your HVAC equipment a little better than the fiber glass crew, but still do little to improve your indoor air quality.

Stepping it up a notch, let’s consider the six-inch deep pleated filters. They’re definitely better (MERV 8 or 9) and only have to be changed 2 or 3 times a year. Now we’re talking improvement in the air you breath.

And finally, the big dogs: HEPA filters. These guys aren’t MERV rated… because they are off the chart, at least 50% better than anything else mentioned above. If you want the best from a filter, go HEPA.

If you really want to get crazy, consider electronic or UV filtration. More on this later.

Pennington Service Company is regulated by the
Texas Department of Licensing and Regulation
P.O. Box 12157 - Austin, Texas 78711
(800)803-9202 - (512)463-6599
TACLB26170E