Is It Normal for Water to Leak Under the Car When the AC Is On?

Posted on: 10 April 2018

You park in the driveway, and it's a few minutes before you actually get out of your car and head to the house. When you do get out and look back, there is a huge puddle of water on the ground under your car where the AC was running. For most car owners, this sight immediately brings about some concerns, and they specifically want to know: Is this normal? Those puddles of moisture left on the pavement after your car has sat idling with the AC on can be worrisome for sure. Check out these tips to keep in mind if you find yourself in a similar situation.

Some drainage from your car's AC is normal.

Think about how an AC works, and it is easy to understand why there is some drainage. In order to cool the air, the AC compressor pulls in warm air and cools it down rapidly, which causes a lot of condensation to occur. All that moisture has to go somewhere. Therefore, your car should have a small drainage line that routes the moisture away from the engine and onto the ground.This will especially be common during the hottest parts of the year, and sometimes, the condensation can be so much that you can't help but think something is wrong. 

The drainage should never look oily or foggy. 

If you see puddling under your car and it is not clear, there could be something else going on. Of course, water dripped onto the ground is going to pick up contaminants that make it look dirty.  However, if the liquid coming from your car appears oily and dirty before it hits the ground, you could be seeing something besides condensation. For example, coolant could be leaking from your car or even oil, so definitely pay close attention. 

Watch out for leaks inside your car when the air conditioner is on. 

The hose that captures condensation from the car's AC unit sometimes deteriorates, and the moisture will leak into your car instead of onto the ground, and this is never a good situation. Pay careful attention to any extra moisture you see when using your AC. Sometimes, it will show up as fogged-up windows as the moisture evaporates in your hot vehicle. Any time you see signs of this, get in touch with an auto service professional, such as Modern Auto Air, immediately so mold and mildew do not develop in the car interior.