We are deep into summer now and our HVACs are running almost non-stop to keep our homes and businesses cool. This process will produce a lot of condensation and if your AC isn’t up for it it can cause some problems. How do ACs handle condensation? A little thing called the condensate line. Have more questions? What are condensate lines? How do they help? Read on and we’ll do our best to give you the rundown on this crucial component!

What are A/C Condensate Lines?

First, a little rundown on how the AC works. As air is cooled or heated inside the HVAC system, it produces humidity. This humidity eventually turns into condensation that must have somewhere to go, otherwise it’ll pool and can cause water damage, mold growth, and more. Enter the condensate line, which essentially functions as a drain line.

Typically made of plastic (like PVC) or on occasion metal, condensate lines connect directly to the AC unit and lead outdoors, through exterior walls. It’s job is a simple one: funnel condensation away from the unit. It does this through gravity, though some units might have a small pump to help get it going. Take a look around your home, chances are you’ll find a little white PVC pipe sticking out from the wall that seems to just drain onto the ground. That’s the end of your condensate line.

So, the evaporator coil works to remove humidity from the air, converting it into water. That water needs to go somewhere of course, so it drains to the condensate drain pan, then the condensate line which deposits the moisture outside. Pretty simple right? It is, until something goes wrong.

How does the Condensate Line Clog?

Any number of things can clog up the PVC or metal pipes. Goo, dirt, algae, rust, microbes, or any combination of them can begin to gather in the pipe. Over time these compounds might grow enough to clog the pipe and block the flow through the drain line.

Condensate Line Problems

There can be a few different kinds of problems caused by a clogged condensate line.

Ice can form on the AC coils and inside the drain line. Because the moisture has nowhere to go, it sits in the pipe or pan and freezes over, causing damage to the system.
Water in the drain pan can overflow and spill its contents inside your air conditioner.
Loose fittings on the drain pipe can cause leaks as well, damaging your drywall or dripping water from your ceiling. Depending on where the AC unit is and the severity of the leak, that could mean a serious amount of water damage.

How Do I Know if My Condensate Line has a Problem?

There are a few ways you can spot a problem in your condensate line. Look for water on the floor nearby your air handling unit/evaporator coil. That’s a sure sign of a problem in your drain lines. Okay, so your system works like this. Your AC will have a drip pan, usually sitting at the bottom of the AC unit. When that pan is full or clogged and/or if the line is clogged, the water will spill over the edges onto the ground.

Another way you may notice your line has a problem is to look out for musty odors or increased humidity inside your home. That’s a surefire signal that the drain system isn’t working as it should.

So, you’ve detected a problem. Now what?

Basic Process for Clearing a Clogged Condensate Line

With a little bit of know how and confidence, clearing a clogged condensate line is totally doable for most homeowners. You’ll need some rags, a wet vac, and vinegar. Here’s a handy, 6 point step to show you how:

Shut off power to your HVAC system. Turn it off at the thermostat, as well as the breaker.
Find your drip pan, which is typically positioned underneath the interior air unit. You may need to remove a sheet metal panel to access it.
There may be water in the drip pan. If so, there is likely a clog in the line. Remove all water from the drip pan using either rags or a wet vac.
Remove and clean the drip pan.Clean all mold, algae, and contamination with a mild soap.
Using your vacuum, remove clogs from the condensate drain line. Find the exterior exit of the line. Use your hand to create a seal around the line and vacuum hose. Turn the vacuum on for about a minute and check to see if the clog has come out.
1. If the vacuum does not clear the clog, you may be able to do so manually. Use a flexible rubber tube to run through the line. If you can’t or don’t feel comfortable with these steps, call an HVAC maintenance professional like ACE.
Clean the drain lines at the access point. This usually looks like a T-shaped vent with a PVC cover. Take the cover off, use distilled vinegar or hot water with mild dish soap and flush the drain. Let the vinegar or soap mix soak for about half an hour and then rinse with clean water. Keep an eye on the drain line exit to make sure water is draining freely.

What about Bleach?

So you saw we mentioned using vinegar to flush the line and you want to know about bleach. Makes sense, it’s a heavy duty cleaner and will kill just about anything it comes into contact with so why not use it to flush out your condensate line? Well, a few reasons.

For one, bleach is strong and the vapors from it can be hazardous to your health. For another, many condensate lines are made up of PVC or other plastics and bleach can eat away at the material as well as the glue used to hold it all together. Using bleach might kill everything in that drain line, but it’ll also destroy the drainline itself!

Meanwhile, white vinegar is potent enough to kill over 80 different mold varieties. It will do the job just fine for your condensate line, with no harmful vapors to worry about, and it won’t eat away at the line itself.

Long story short, choose vinegar for rinsing out your line, not bleach.

Now you know what they are, how they work, how to detect a clog, and even how you can clear the clog yourself!

Still have a problem?

Have any questions or an unruly clog you just can’t do? Would you rather have a professional come out and inspect your AC to avoid the headache? No matter the reason, ACE Home Services is here for you! We’re happy to perform routine maintenance and line clears, or total system replacements and everything in between.

A/C Unit Condensate Lines and You