How to keep ac drain line clear

So your AC drain line is clogged and you are trying to figure out what to do next. You've come to the right place.

Being an air conditioning company located in the heart of Central Florida, we are well acquainted with clogged AC drain lines. Our year round high temperatures and high humidity make us prone to higher rates of clogged AC drain lines than just about anywhere else in the country. And our technicians collectively unclog and clean thousands of AC drain lines each year. 

So please trust us when we tell you to put away your bleach and your vinegar. 

Despite it being common for people to recommend using a vinegar or bleach solution to clean your AC drain lines, we're going to tell you why it's not a good idea.

Bleach and Vinegar are Corrosive to metals

The reason you shouldn't use bleach or vinegar to clean your AC drain line all boils down to the fact that these chemicals are corrosive to metals. In other words, they literally eat away at metal.

Why is that a problem you ask?

They Can Damage Your Evaporator Coil

The evaporator coil is inside of your indoor air handler. It is normally just inches away from your AC drain line.

The job of an evaporator coil is to cool your air by removing moisture. The moisture from the evaporator coil then collects in the drain pain and is directed into the drain line and out of your home.

Evaporator coils are normally made out of copper or aluminum. So what happens if a corrosive chemical such as bleach or vinegar comes into contact with your evaporator coil? It's going to corrode!

Using bleach or vinegar can be especially risky if you think your AC drain line is clogged. If the drain line is clogged, the corrosive mixture will simply back up in your drain line and flow into your drain pan, which in turn can damage your evaporator coil.

So if using bleach or vinegar can damage your evaporator coil, what should you do instead?

How To Clean A Clogged AC Drain Line

Failing to clean your AC drain line will cause your unit to turn off when it's clogged and potentially cause water to pour out onto the ground.

So you definitely need to be cleaning your AC drain line regularly. 

But what is the best way to do it? Well, here is how we do it when we perform an annual AC maintenance for our customers.

Attempt To manually Clear any blockage

The first thing you should do is to use your hands to manually clear blockage. Find the end of your drain line (located outside of your home) and make sure it's not clogged. Reach your fingers inside and attempt to clear away debris.

Use A Shop Vac And Water

Next, connect your shop vac hose to the end of your drain line (the one outside). If the hose connects loosely, you can use a cloth or duct tape to create an airtight seal. Turn the vacuum on.

At the same time, get a gallon jug of water and a funnel. Slowly pour water into the drain line access point near your air handler. The shop vac should suck the water (and any debris) out of your drain line and into your vacuum.

Be careful because if the clog does not loosen, water will back up into your drain line and potentially leak onto the floor.

Use A Drain Snake

If you have a very stubborn clog that doesn't come out with a shop vac and water, then you can try using a drain snake. Push the drain snake down into the drain line access near the air handler. Make sure the that the drain snake does not go towards your air handler or you could potentially damage the evaporator coil.

Rebuild The Drain Line

In some worst case scenarios the clog is so bad and hardened, that the only way to fix it is to completely rebuild the drain line. We have only had a few situations that warranted this extreme approach, but we do want to include it as another option.

Join Our Comfort Club Preventative Maintenance Program

If all of this sounds "nice", but you just don't have the time or desire to do this on a regular basis, then we invite you to sign up for our Comfort Club annual AC preventative maintenance program.

We'll come to your house once or twice a year (you choose) and do a complete tune-up on your system. This always includes cleaning the drain line.

And if you choose to sign up for the twice a year plan, then we will always come unclog your drain line for free, which can end up saving you a lot of money (Call (407) 291-1644 to sign up).

How To Unclog An AC Drain Pipe

Reading Time: 3 minutes

A clogged AC drain pipe can cause serious headaches for you as a homeowner, but it shouldn’t have to. Because your AC plays such an important role in your households’ daily comfort, you’ll want to address a clogged AC pipe right away. The great news is, it is relatively straightforward to do, with some guidance from the experts at Art Plumbing AC & Electric. Staying on top of all the elements that keep your property going can be stressful and seem tedious at times but the best way to avoid a clogged condensate drain line is through regular care and preventative AC maintenance.

Signs Of A Clogged AC Drain Pipe

One of the most obvious signs of a clogged AC pipe is that your air-conditioning system has stopped working. Your AC drain line ensures that excess condensation is removed from your air-conditioner. When operating properly, you’ll probably notice a small trickle of water at the end of a PVC pipe outside your home somewhere, which is where the moisture travels. This is where problems occur and may lead to a backlog of water and/or a blockage. Other signs of a clogged AC drain pipe include:

• Water flooding around the air handler unit.


• If your AC is not cooling or running at all due to a clogged AC pipe, the water safety switch would have been triggered preventing it from operating. There could be water around your safety switch which would have triggered it to cease functionality.


• A moldy smell throughout the house. This could be as a result of a build-up somewhere inside the system. Your AC is still running but doesn’t smell good. Mold has been known to cause health issues so be sure to act on this right away if it is the case.


• If your condensate pan is full more often than not, you could be dealing with a potential clog. In order to prevent mold from growing, act on this as soon as possible.


• If you notice water damage around your AC unit, near the fan or on the floor, this could be a sign of a blockage somewhere along your drain line.

Why Is My AC Pipe Clogged?

An AC pipe usually develops a clog due to algae. Because of warm air that blows over the cold evaporator coil of the HVAC, the drain pipe can get pretty humid; and along with the condensate traveling through the pipe, these conditions are perfect for algae to thrive. If your AC is constantly running (which in most South Florida homes it does), it is more likely to clog up more often than not. Mildew, mold and other types of bacteria and fungi have been known to cause issues for your AC.

Unclogging Your AC Pipe 

Regular, smaller clogs will be relatively easy for you to fix. We suggest steering clear of using bleach to unblock your drain as the chemicals may cause more damage to the essential elements of your AC system. The following steps will assist you in getting rid of any mold, algae or mildew that has built up and possibly causing a clog.

• Step 1: Turn Off The Power To Your AC

  Turn the power off at the thermostat and at the breaker.

• Step 2: Find Your AC Drain Line

  This is a PVC pipe that is usually situated outside, near your condenser unit. You might require a bucket at this point should your drain line be full.

• Step 3: Identify The Point Of Access On The Drain Line

  This will most likely be a T-shaped vent with a cap covering the top of the drain. You can inspect for a blockage by removing this cap.

• Step 4: Assess The Clog

  Have a look at the AC drain pipe and see if the blockage is visible. If you can see what is blocking the pipe and can remove it manually, do so by wearing protective gloves. If the clog is too far down, move on to step 5, below. IMPORTANT TIP: Make sure you don’t push the blockage further down.

• Step 5: Flush With Vinegar Solution

  Vinegar has cleaning properties due to its acidity. If the smell of vinegar is too strong, you can mix it with some soap and warm water. Throw a quarter cup of regular, white, distilled vinegar into your drain line through the opening where you have removed the cap. Once it is full, you can stop.

• Step 6: Leave The Solution For 30 Minutes

  After 30 minutes, flush the pipe out with water and ensure that the water is flowing as it should do. If it does not flow normally, the clog is too big for a DIY remedy and will need to be addressed by a professional, offering air-conditioning services.

• Step 7: Repeat Every Month

  Repeat steps 1-5 every month to ensure that you stay on top of any build-up and prevent running into issues with the usage of your AC.

We don’t suggest undertaking serious HVAC repairs on your own simply because of the risk of causing further damage, however, if you are sure you’re sitting with a clogged AC pipe, you shouldn’t have much trouble with this fix. If you still can’t seem to get your AC running optimally, get in contact with our HVAC systems technicians to avoid further costly complications by calling 1-800-475-1504.

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