Why Do Air Conditioners Produce Water?

If you’ve ever stood outside near a window air conditioning unit, you may have noticed some water collecting below it. You may have had to clean up after your own air conditioner following a leak. Air conditioners produce water as part of the cooling process. Some of that water is needed to help cool the air, while the rest is sent out the back of the unit. Learn why air conditioners produce water to help them prevent leaks and work at top efficiency.

Humidity in the Air

Higher temperatures in summer frequently bring higher humidity. Humidity refers to the amount of water in air. One of the ways your air conditioner makes the air more comfortable is by removing some of this moisture, thus lowering humidity levels in your home.

How Air Conditioners Work

Air conditioners cool air through refrigeration. Inside your air conditioner are two sets of coils that are connected by a condenser. One of the coils is kept hot, the other cold. Chemicals inside the coils evaporate and condense over and over again, cooling the coils. This in turn cools the air blowing over them. The cooled coils also force moisture out of the air; when the air condenses on the coils, it wrings water out the same way that air condensing on a cold can of soda produces moisture on the sides.
Some of this water will re-evaporate and help to keep the coils cool. The rest of the water runs out of the back of the air conditioner.
Seeing your air conditioner produce water is a good sign; it means that the air conditioner is working properly. If your air conditioner is not producing visible water, it could mean that there is a problem —the water may be running somewhere it shouldn’t, or the water may be freezing into ice on the coils.

Leaking Air Conditioners

While all air conditioners produce water as part of the cooling process, this water is meant to run out of the back or out of a specific drain line. If the water is coming from somewhere else (pooling in your home, for example) it means that your air conditioner is leaking (and therefore not working properly).

Plugged Drain Lines

Your air conditioner needs to drain the vast majority of the water it produces. If the drain line is plugged or clogged, water will collect inside. This can result in problems such as leaks from seams or other areas of the air conditioner.
If you notice your air conditioner leaking water indoors, unplug it and take a look at the drain line. Unplug the drain line and make sure it’s clear before turning it back on.

Ice Collection

When there is too much water inside an air conditioner, the internal fans blow the excess water onto the unit’s cold coils. Over time, the coils can ice over, which can significantly affect your air conditioner’s performance. When you turn an affected air conditioner off and the air inside heats up, the ice melts and causes a puddle of water to appear beneath the air conditioner.
In case of icing, unplug the air conditioner and tilt it back slightly so that the water can drain out instead of in. Make sure the drain line is unplugged to let it drain — this can sometimes be the cause of excess water. If there is still ice, thaw it with a hair dryer to get your air conditioner working properly again.

Warm Air Infiltration

If your window air conditioning unit isn’t properly sealed, warm outside air could be infiltrating your home. While you may not notice this while your air conditioner is running, your air conditioner will. The warm outside air will hit the cold air conditioner and condense, which will force the humidity out of the air and cause it to drip down the sides of the air conditioner. If this happens to you, seal up your window to keep the warm air out.

Understand Your Air Conditioner

By becoming better acquainted with your air conditioning unit, you’ll be able to keep it in good working condition. Learn more about how your air conditioner operates and what behaviors are normal during its use in order to make better decisions regarding its maintenance.