Can You Run an Air Conditioner Without a Filter?

Can You Run An AC Unit Without a Filter

Never run an AC without a filter; it will cost you more money than you can imagine. You may think that the AC will work better if you run it without a filter, but that’s not true, and this will be the same case for all HVAC systems. (Below) you can read more about the consequences when running an AC without a filter.

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What Happens If You Run an AC Without a Filter?

The blower motor, electrical system parts, and all air ducts throughout your home will get dirty. But then you have the air conditioning evaporator coils; now they call it an A-frame. Typically there are two A’s shape design coils, and the fins are tiny so that any hair dust will block these coils. It becomes less efficient, so it needs more energy to run and is not moving as much air resulting in ice build-up due to low airflow. 

An AC with low airflow will result in ice build-up in the system leading to a water leak and other costly issues. When ice build-up occurs in the system, the ice will drip straight to the floor and, even worse get all electrical parts wet. And now you have to deal with water intrusion in your home, resulting in drywall and carpet repair. So, as you can see, one problem leads to another, which means you will end up spending more money than expected.

Also, the heating system is not as susceptible to dirt and stuff like that. As I mentioned earlier, all air ducts in your home will get dust build-up resulting in the dust flying all over the place. But at the very least, it will cost you extra money because you will not get the airflow through the system that you should. So remember, never run an AC without having a filter in place. 

After placing a new AC filter, I now recommend installing a weatherstrip around the system’s closet door; use this tip if the system is in the hallway, built-in in a closet. After installing a door weather strip, you will have to push it a little harder when you close the system closet door. Because the weather seal seals it well and tightly around the door, providing greater efficiency. (Below) you can read what to look for when buying an AC filter.

When Replacing an AC Filter

Replacing your AC filter is also vital to keeping your home clean, as we know, and choosing the right filter will definitely make a difference. Let’s continue reviewing how important it is to replace these filters and what factors you’ll need to consider before buying your new AC filter as follows: 

How Often Should You Replace an AC Filter When Living Alone?

First, the general rule of thumb is this, you should replace your air filter if you have a perfect one every three to six months, and that’s if you’re a person who lives alone. You don’t need it that often, but make sure it’s on a schedule and get it on your calendar. So you know when you’re going to change those air filters and don’t go a year in between because that’s when everything gets clogged up.

How Often Should You Replace an AC Filter When Living With Family?

Now, if you live with family and many people come and go and doors open and close. The house is frequently lived in; then you want to change your air filter, even if you have an expensive filter, probably every three months

How Often Should You Replace an AC Filter When Living With Family and Pets?

Now, if you add pets into the mix, that’s when it gets a little bit interesting. If you have only one pet, I will replace it every two months because now you have a pet dander. You have the pet going in and out and bringing things in their fur that you usually wouldn’t have if it were just people. 

If you have more than two pets, I recommend every thirty days because you will have a lot more stuff in your house. Still not sure why you should replace your existing AC Filter? (Below) you can read more about why you should replace your existing AC filter and why.

Why Should I Replace My AC Filter?

We’re looking to get all those things out of the air that’s circulating in the air that we breathe inside our homes. If we can create a clean ambient to live in, cleaning the house, like regularly dusting and vacuuming. And always replacing the AC filter on a schedule will keep your house free of dust. Again, something as small as an air filter in your house can make a difference and if you have pets, do it regularly, every month or so. 

How to Choose the Right AC Filter

The best way to choose the right AC filter is by understanding the MERV ratings. When shopping for AC filters and your heating system, you may have seen filters that claim to have different MERV ratings. And you may be impressed by the number of choices available in AC filter size. Once you have a clear understanding of how MERV ratings work, you’ll be able to choose the right AC filter for your home. Let’s review (below) how MERV ratings work so you can have a clear understanding.

What is MERV Rating on AC Filters?

The MERV rating system is a handy way to compare air filter performance. MERV stands for (Minimum Efficiency Reporting Value). The MERV rating of a filter is derived from a somewhat complicated test developed by ASHRAE (American Society of Heating, Refrigerating & Air-Conditioning Engineers). 

How is the MERV Rating on AC Filters Obtained?

A collaborative aerosol generator produces a mist of known particle size, such as a fine dust mist sent through a filter being tested. A particle count is pulled before and after the filter and repeated several times for each particle size; twelve different particle sizes are tested. Filtration efficiency is indicated as a ratio of downstream to upstream particle counts. These ratios are ultimately averaged to help label a filter with a MERV rating. 

Now that we understand how the MERV rating is developed let’s review what it means to you. The MERV rating tells you how capable the filter is at removing small allergenic particles and other air contaminants and promoting good IAQ (Indoor Air Quality). So, (below) you can read the MERV rating numbers that you’ll need when choosing the right AC filter. 

How to Choose an AC Filter By MERV Rating

MERV ratings are assigned in values from 1 to 16; the higher the number, the better the quality. 

  • MERV rating 1 to 4. 
  • MERV rating 5 to 8. 
  • MERV rating 9 to 12 (Recommended).
  • MERV rating 13 to 16.

How Does an AC Filter MERV Rating 1 to 4 Work?

MERV ratings of 1 to 4 mean that the filter will provide the minimum filtration and protection for your AC. In contrast, generally inexpensive filters in this range do not promote good indoor air quality. 

How Does an AC Filter MERV Rating 5 to 8 Work?

MERV ratings of 5 to 8 are widespread pleated filters that will trap about half of the particles of a small micron flux that effectively promote good indoor air quality. 

How Does an AC Filter MERV Rating 9 to 12 Work?

MERV ratings of 9 to 12 (Recommended) represent better-pleated filters and trap most particles down to 3 microns; these promote better indoor air quality and are the most popular filters. 

How Does an AC Filter MERV Rating 13 to 16 Work?

MERV ratings of 13 to 16 are very efficient but can restrict airflow in the system. They collect particulates at the sub-micron level that promote excellent indoor air quality and can also be very expensive. However, this particular MERV rating of 13 to 16 can also affect the airflow in the system. Therefore, I recommend choosing the MERV rating of 9 to 12 to avoid low airflow in the system. Remember, as I mentioned earlier, low airflow results in ice build-up in the system. 

Should You Put an AC Filter in the Return Vent?

In this case, it is either one of the two, meaning if you already have a one-inch filter in the system, don’t use the media filter in the return vent. In other words, don’t double filter because this will create airflow restriction, and as I mentioned earlier, this is going to lead to other issues with your AC.