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The Hidden Dangers of a Clogged Condensate Drain Line on Your AC

In a previous article, we discussed the importance of a good spring cleaning and tune up of home’s air condition system. We mentioned how some bargain HVAC technicians won’t even bother to take the panels off of an AC unit to clean the evaporator coil. This can ultimately defeat the original purpose of a cleaning and tune-up. Another area of concern is your condensate drain and the problems associated with a clogged condensate drain line. Once you understand the purpose of a condensate line and the problems a clogged drain or line can cause, you’ll better understand how important it is to make sure your condensate drain line is functioning properly.

What is your Condensate Drain?

If you’ve ever left a cold canned beverage on a picnic table on a hot summer day, even for just a few seconds, you’ll notice that moisture forms on the outside of the can drips down quickly to leave a water ring on the surface of the table. It’s why you probably use coasters inside your home, especially if you have wooden tables. This moisture from condensation can cause damage. Your air conditioning also produces this condensate as it cools the air through its evaporator coil. Your condensate drain is designed to provide a path to remove this moisture and dispose of it in a way that won’t cause damage to the unit or your home or property.

If you look at your AC unit, you may see a small pipe, generally made of PVC, that serves as your condensate drain. It is often located near the ground or a drain. If water is dripping from this line, that’s good news, as it is likely doing its job. The problem is, this line can get clogged, often without your knowledge. Like that cold can on a nice wood table, it can also cause some ugly, and potentially expensive problems.

The Potential Problems of a Clogged Condensate Drain Line

Your AC drain line will include a trap, not unlike the U-shaped traps under your sinks. This is to prevent unwanted air from getting into your closed AC system. This trap, along with the warm, moist air that is under most AC systems are, unfortunately, a perfect breeding ground for algae. If this algae builds undetected and unchecked, it can cause a clog in the drain line. This can back up moisture into your AC system and into the walls of your home. This, in turn, can lead to leakage and overflows which can lead to mold and even a complete system shutdown. These clogs can be disgusting and the damage significant.

Making Sure Your Condensate Drain Line Is Cleaned Properly

Quite simply, there is only one way to make sure your condensate drain line is cleaned properly. That is to have your AC unit tuned-up and cleaned each Spring from a trained, qualified, and quality technician like those at Althoff Industries. Some DIY’ers will attempt to determine if there is blockage present by pouring water down the line from the tee valve, assuming if they see or hear water coming out on the other end, the drain is clear. Sadly, this is also how some bargain HVAC technician assure themselves, and their customers, there is no blockage. But as you can see in the photos, nasty blockages can occur BEFORE the tee, at the outlet of the evaporator coil.

Why do we pay attention to something as seemingly simple as condensate drains? Because at Althoff Industries, serving the greater Chicago area, we’ve built our business by doing what we say we will do and by doing it the right way. You have a significant investment in your home and your AC unit. We have our reputation at stake. Call us for a quality AC check from the professional HVAC technicians at Althoff.

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