Where Does the AC Drain Line Go?

Apr 06, 2021

Besides changing your home’s air filter, the most commonly-needed maintenance service is drain line clearing. So what is a drain line? Where does it go? How can you tell if the drain line is clogged? Newcomb and Company is here to answer some of the most common questions we get from customers about AC drain lines.

What is a Drain Line?

Before we dive into the drainage pathway, you might be wondering, “What is a drain line?” Your drain line—also known as a condensate line—is responsible for carrying excess condensation away from your air conditioner.

Have you ever noticed that warm air in the south tends to feel “muggy?” This sensation happens because the warm air molecules can carry more water than cool air—making the air feel both hot and moist. When your air conditioning system cools the air, it also causes the air to release this extra moisture. This condensation is caught by your AC drain pan and carried away by your drain line. So where does the AC drain line go?

Where Does the Air Conditioning Drain Line Go?

So what does the AC drain line do with excess water? It carries the water from your indoor unit outside and deposits the water onto your grass. Your drain line often travels from your indoor units to outdoors near your external AC units. If you walk outside and look near your HVAC system, you may see a pipe connected to your home. This is where your drain line ends.

Is My AC Drain Line Clogged?

Because your drain line ends outdoors to deposit excess moisture, this also leaves a clear pathway for debris, dirt, and other contaminants to enter your system. The dark, moist environment of your drain line also makes it susceptible to mold, algae, and sludge buildup. Collectively, these factors can cause your drain line to become clogged. In these cases, the extra moisture produced by your AC system will fill up in your drain pan and eventually begin leaking into your home.

What Happens When Your Drain Line Clogs?

Clogged drain lines can spell trouble for your home, presenting two primary problems you should keep an eye out for—water damage & ineffective AC systems. Let’s take a look at these two issues:

Water leaking and damage

The water leaking caused by a clogged AC drain line can present risks for your home. This moisture can cause mold, high home humidity, water damage, bacterial growth, and other water-related problems. [see also: what should I do when I have a water leak?]

Ineffective or Shut Off Air Conditioning

There is a float switch underneath most drain pans that will detect when the water is overflowing. This safety switch will shut off your full or partial AC functioning to prevent serious water damage.

Some units are designed to turn off partial functioning. In these cases, the outdoor system will shut off to prevent moisture intake. Meanwhile, the indoor unit will continue to run—but it will likely be blowing warm air. Other units will shut off entirely when the float switch is triggered. As your drain line is slowly capable of carrying away some of the extra moisture, your system may begin working in cycles.

Thankfully, early drain line issue detection can prevent serious damage to your home and our AC system. Here is insight on how you can clean your AC drain line. Your AC drain line is also checked and cleaned during your annual maintenance visit. Keeping up with manufacturer-recommended maintenance can help prevent drain line issues from occurring and keep your system working efficiently.

Newcomb and Company HVAC Service

If your drain line becomes clogged or you are due for an annual maintenance visit, the experts at Newcomb and Company are here for you. We proudly serve homes and businesses throughout Raleigh, Wilmington, and nearby areas like Knightdale, Clayton, Cary, Garner, Castle Hayne, Leland, Carolina Beach, and beyond. Make your appointment here to get started today!


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