Pleated Filters: Why They Are So Effective

August 20, 2020

Filters are an important part of many devices that you use every day in Seattle. Engine filters help to keep your vehicle’s engine running strong, coffee filters help to keep bitter coffee grounds out of your morning cup of joe, and pool filters help to keep your pool’s water clean and refreshing.

One of the most important filters in your life, though, is the air filter for your HVAC system. Without this filter in place, your HVAC system won’t work properly, and your family will be breathing in dust-filled air. One of the most common types of filters, the pleated filter, is also one of the most effective. Here’s why the pleated shape works so well.

Larger Surface Area

Here’s an interesting fact: Your small intestine, an important part of your body’s digestive system, is over 22-feet long. How can something so long fit in such a small area of your body though? It’s all because your small intestine is folded. This allows your small intestine to have a longer length without taking up unnecessary space.

This same principle of folding is one of the reasons that a pleated filter is so effective. If you were to remove the frame from a pleated filter and stretch it out, you would discover that the actual size of the filter is far larger than its frame. However, thanks to the pleats, it is able to fit this large size into a small package.

This extra surface area allows your filter to remove far more dirt than it could if it weren’t pleated since there are far more possible locations where a single piece of dust can land. Plus, the pleats in the filter add strength to its structure so that it stays in place until it needs to be changed out.

Changing Airspeed

Another advantage of the pleats on a pleated filter is that they help to capture smaller particles. While some filters are rated to capture tiny particles, these tend to be reserved for people with severe respiratory illnesses. For most people, a standard filter that captures a majority of dust particles will suffice.

However, just because you have a less-dense filter doesn’t mean that you want all of the smaller particles to get through. Fortunately, though, a pleated filter changes the airspeed and disturbs the air as the air flows through on its way to your HVAC system. Though it’s a small change, it can be enough to cause some smaller particles to stick to the filter instead of being pulled through the system.

To illustrate this concept, think of a valley in the middle of a mountain range. If a front moves through, the winds in the valley are likely to be faster and more tumultuous than the winds on top of the mountain because the winds accelerate as they go down the side of the mountain and mix with air from other areas in the valley.

This same basic principle takes place in the “mountains and valleys” created by the pleats on your filter, which makes even the most basic pleated filters quite effective at capturing many types of airborne contaminants.

Heightened Fiber Density

If you remember from elementary school science, the word “translucent” means that light can pass through an object, but the object can’t be seen through. “Transparent,” on the other hand, identifies an object that can be seen through. When it comes to an air filter for your HVAC system, a translucent filter is key.

If a filter is translucent, it means that the gaps between the individual fibers are so small that they can’t be detected by the human eye. Since the gaps are so small, it is easy to understand why it is very difficult for dust to pass through. However, if a filter is transparent, it indicates that the gaps between the fibers are much larger, providing many more places for dust to pass through.

Transparent air filters exist in the form of fiberglass filters. These older filters, identifiable by their distinct blue color, have large gaps between the fiberglass fibers. Therefore, even though a fair amount of dust will still be captured because of the disturbance of the air as it flows through the filter, quite a bit of dust will make it through. Unfortunately, this allows the dust to become increasingly dispersed, which can lead to respiratory issues for your family members.

Fortunately, pleated filters utilize coverings such as polyester or cotton, which are more finely spun than fiberglass filters. Thus, these filters are, as far as the human eye is concerned at least, translucent, meaning that they are effective at capturing a wide variety of contaminants.

Higher MERV Rating

Another important consideration when choosing a filter is the MERV rating of that particular filter. The acronym “MERV” stands for minimum efficiency reporting value. Filters with higher MERV ratings are able to capture smaller particles in the air. Typically, a filter with a higher MERV rating will use cotton for its filter material, taking advantage of the high fiber density of cotton.

Fiberglass filters are typically rated from 2-4 on the MERV scale. Low-end pleated filters typically rank around a level 6. A filter that’s rated MERV 6 can capture most household dust, lint, and pollen. The MERV scale goes all the way to MERV 20, which is reserved for HEPA-type filters that are typically found in hospitals.

For the most part, a MERV 20 filter isn’t necessary for a residential application. In fact, a filter that’s this dense would likely damage most HVAC systems because it wouldn’t allow enough air to get through. If you need exceptional filtering, though, you’ll be fine with a filter in the MERV 11-13 range.

We Keep Your HVAC System Going Strong

At Brennan Heating & Air Conditioning, we know what it takes to keep your HVAC system running efficiently. In our 30-plus years of experience, we have learned a lot of tricks and insights that help us take care of our customers’ needs. That’s why so many residents in Seattle, Lynnwood, and the Puget Sound area trust us.

In addition to handling HVAC installations, repairs, and tune-ups, we can work with water heaters. We can also take care of electrical needs to ensure your home runs safely and efficiently. To ensure that your HVAC system runs efficiently at all times, we offer duct cleaning services so that your air will flow freely without being restricted by dust.

Our commitment to service has resulted in several awards for our company. These include the Puget Sound Energy-Efficiency Action Award, the Snohomish PUD’s Top Producer Award, the Angie’s List Super Service Award, and an A+ rating from the Better Business Bureau.

Most importantly, though, our customers consistently leave us five-star reviews, thanking us for our professionalism and commitment to integrity and value. If you want to increase the performance of your HVAC system, contact us at Brennan Heating & Air Conditioning today.

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