All About Filters

Yes, we know. We talk about filters…a lot! Why? Because they are so darn important!

Sometimes called an HVAC filter or media filter, they get a lot of attention because they’re key to keeping your home’s comfort system—including your heater and AC—running at its best.

Let’s answer a few common questions, and get to the bottom of why media filters are so important, and our recommendations for how often you should be switching them out.

First up, what is a media filter?

If you want or need to improve the indoor air quality, media filters are an HVAC system’s best defense. Media filters do an exceptional job giving you clean air and are one of the highest quality filters available for homes. They catch all sorts of particles and contaminants in the air, stopping stuff like mold, pollen, dust, dirt, pet dander, smoke and other contaminants.

Media filters are mounted on a return duct line on your home’s HVAC system. They protect against particulates from entering your home through the air system. Media air filters last much longer than a basic 1” air filter along with being more effective in a number of ways.

Okay, but how do they work?

A media filter is installed on the return air duct of an HVAC system. Air going through the system goes through the filter. The filter removes airborne contaminants and material before it is sent out into your home.

The primary difference in a media filter and a typical air filter in most HVAC systems is its size. Media filters are 4-5 inches thick compared to a 1” filter. This is part of its better output and efficiency.

Are there different kinds of filters?

Yep! In fact, there are seven types of common filters which are made for home use.

• HEPA filters

• UV light filters

• Electrostatic filters

• Washable filters

• Media filters

• Spun glass filters

• Pleated filters

Each type of filter has pros and cons. What’s important to you will differ based on your family’s needs and your home. Some people need HVAC system filters that will maintain their home’s air free of irritants and pollutants. Others just need a standard filter to get the job done.

Normally, high-efficiency filters that are cost-effective are best for homes. However you could well have more factors to consider. Homeowners with pets is one simple example. Do you live in a climate where mold is more likely? Have you had mold in the home before? Do you have specific allergic concerns or needs? These are just a few examples.

What do I need to know about MERV Rating?

Filters are rated and categorized by a MERV rating – Minimum Efficiency Reporting Value. This rating number is from ASHRAE – the American Society of Heating and Refrigerating and Air Conditioning Engineers. The MERV rating of a filter ranges from 1-16. The range gives you a measurement of the size of pollutants the filter will stop, from 10 microns to as small as 0.3 microns.

I’ve got a simple 1” filter. Should I be concerned?

A basic air filter is affordable, easy to buy and will do a satisfactory job keeping an HVAC system and your home clean. There are additional issues you might want to consider. Are you still experiencing some of these problems?

• High static pressure. 1″ filters come in different MERV ratings. The greater the MERV, the smaller impurities it can remove from the air. Unfortunately, pleated 1″ filters with a MERV rating over 12 can raise the static pressure in your HVAC system. If the pressure becomes too high, it may hinder airflow. This may lead to uncomfortable conditions in the home and an inefficient – or in time damaged or failed – heating and cooling system.

• Poor filtration. To avoid the static pressure problem, you might use a low-MERV filter. While it might do the job in some categories, it won’t be helping the indoor air quality of your house much. It can be difficult to balance adequate air filtration with good, proper airflow.

• Remembering to change the filters. In most cases with standard 1” filters, you need to wash or change the filters every 1-3 months. This depends on your home environment, your family’s health and comfort needs and how often you’re running the heat or AC. Then, if you’re guilty of not changing the filters as often as you should, what does using 1” filters actually mean?

• No smell control. 1″ filters catch particles and contaminants in the air, however they do little or nothing to fight odors or smells.

What advantages does a media filter have over my 1” filter?

Media filters provide a higher filtration capability without the disadvantages. Generally, you have a high-MERV level without the poor airflow or static pressure. A media filter is excellent because:

• They are thicker. A media filter simply has a lot more surface area than even a high-MERV 1” filter. 1″ filters don’t have enough area to supply good filtration and good airflow. A media filter’s surface area means you get filtration of bacteria and allergens down to 0.3 microns without the static pressure problems.

• Easy upkeep. To switch filters, which needs to be done only 1-2 times a year, open a door on the side of the box, remove the old filter, put in the new filter, close the door.

• You can upgrade the media filter. A F100 filter has a MERV rating of 11. It’s easy to go to an F200 (MERV 13) or F300 (MERV 14) with the same filter box.

• Odor control. Another option with a media filter is using a carbon-coated filter. This is a great option if you need odor control in your home. A filter with activated carbon absorbs odor. Carbon media filters have a 16 MERV rating. It will filter out mold, bacteria and viruses.

I know I should be switching my filters, but how often do I really need to change them?

Depending on the type of filter you have, we recommend swapping them out as follows:

• Standard 1” Filters: We recommend inspecting these monthly and changing as needed. At the very least, a 1’ filter should be switch out every 3 months.

• Media Filters: We recommend inspecting and replacing your media filter two times per year. A handy way to remember is when you switch your system over from cooling to heating and vice-versa. If it’s time to replace your filter, we have filters for nearly every make and model of HVAC system at THE VERY BEST PRICES. Seriously…we’re cheaper than Amazon, WalMart, and the big-box hardware stores. Oh…and they ship for free. You can visit our filter shop here.

At CTR Heating and Air we specialize in HVAC, furnace repair, a/c repair, and installation of new equipment, call us for a free estimate. We’ll evaluate your system and help make recommendations for optimum value. After all, we want to keep you cool all summer long and warm in the winter. You can also schedule a visit online and one of our technicians will talk about how we can help with your heating and cooling needs.