What happens if I run my A / C without a filter is a common question posed by many homeowners. It seems like it would be no big deal if there were no air filter in the air conditioner unit. After all it’s just a flimsy, little paper item. And what difference could it make if there were no air filter in the house anyway? Well, you’d be wrong. Dead wrong.

Consider this: you already know if you don’t clean your house on a regular basis: your counters, floors in the bathroom and other living spaces, they would—in the space of a month—gather a noticeable amount of dirt and dust. This equals the amount of debris your air filter builds up in the same period. And we’re talking about a little filter, in which all that particulate matter would be concentrated, not spread out over the larger areas of your home. Are you starting to get the picture?

People ask: well, how important is a clean air filter? They misunderstand what the function of an air filter is, believing the purpose of it is to clear the air of dust, pollen, pet dander, and other allergens you breathe into your system. The air filter mesh can capture some dust coming from the vents. But the standard air filter is not designed to snare very fine particulate matter in the form of pollen, pet dander, and additional types of allergens. HEPA filters are designed for removing these types of things, but that is a topic for another blog.

The core task of an air conditioner filter is the protection of the air conditioning alone. It is engineered to keep damaging debris away from the components of the central air conditioner. Not changing the air filter of your air conditioning unit will interfere with the air conditioner’s ability to keep you and your home cool.

Clogged A / C Filter Symptoms

Duct and Blower Fans

Air conditioner air filters have a time limit on how well they can continue to remove fine particulate matter from the air. Being a small part, they will soon accumulate enough dust and dirt, thwarting their ability to protect the central air conditioning unit from harmful material.

When to replace the air filter in the home is important to know; otherwise your air conditioner will run less efficiently; your power bills will start to surge; and the air filter will be choked with debris, unable to accept the debris traveling from your ducts and blower fans. What happens instead is the ducts and fans experience the buildup of debris the air filter can no longer handle.

Debris such as dust will congest the moveable components: the ducts, blower fans and valves. As a result of jammed-up parts the air conditioning will use more power to overwhelm the blockage. Too much dust on the air conditioner parts forces it to consume more energy and drive up your power bills.

Wear-and-Tear Problems with Running the A / C Without a Filter

It isn’t only the dirty air filter, whose performance is affected; the ducts will suffer as well. Built-up dust on the ducts will cause deterioration of the moveable components, forcing them to operate at a slower rate, using up more power. The increased wear-and-tear on the unit will shorten its service life from five to ten years. That means the average life of a central air conditioner of 15 to 20 years will be shortened to—at the most—5 to 10 years instead. This is what can possibly happen if you don’t change your air filter on a consistent basis.

Moreover, not changing a dirty air filter regularly will cost you in replacement parts as they are wearing out faster than they were intended to. Buying replacement filters is a drop-in-the-bucket compared to how much more money you’ll end up spending to cover major repairs brought on by a clogged air filter of your air conditioner.

Can I Run My A / C Without a Filter for One Night?

You say, okay, I get it. But in the next breath some homeowners ask: can I run my A / C without a filter for one night? Or, can I run my A / C without a filter for one day? The answer is the air conditioner will still not run as well whether it’s one day or one night. It’s a slippery slope. One night becomes one day becomes one week because you’re too busy right now.

So now you know what happens if you don’t have an air filter in your house.