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How the Condensate Drain in Your AC Works

waterYour refrigerant-based air conditioning system doesn’t use water to cool down the air (that’s what swamp coolers do). But the process of evaporating cold refrigerant in the indoor coils of the air conditioner creates water moisture. So when you hear the sound of water dripping inside your AC, that’s part of the normal process of cooling your home. The air conditioner is getting rid of the moisture that built up.

The way it removes this moisture is with the condensate pan and drain. We’re going to look into this component of your air conditioner, because if it develops problems, you need to call us for air conditioning service in Howell, MI.

The Purpose of Condensate Drain

The reason moisture forms while the AC runs is because the cold coils cause water droplets in the air to condense along their surface. It’s the same effect you see when you take a cold beverage can out of the refrigerator: as outside heat starts to enter the cold can, water moisture turns into droplets along the surface. It’s the same with the coils, except cold refrigerant in the coils is absorbing the heat and causing moisture condensation.

These water droplets have to go somewhere. If they aren’t properly removed from the AC cabinet, it creates numerous problems: water damage in your home, damage to the AC, a perfect environment for mold, mildew, and other growths to start in the air conditioner and the home. To prevent all this, a condensate pan catches the water and it then pulls it through the drain.

How the Condensate Drain Works

In the standard air conditioner set up, the condensate pan is placed below the set of coils, so the water drips from the vertical coils and down into the pan. The pan isn’t deep, only about an inch, but the drain quickly removes the water thanks to the action of a condensate pump. The water then either enters the wastewater system for the home or drains to the outside of the house through a PVC pipe.

Condensate Drain Problems

The condensate system for an AC can run into problems with years of use—especially if the cooling system doesn’t receive annual inspections and tune-ups to clean and check on the drain and pan. The plastic pan can crack over time, often because of heat from the furnace that’s located below it. This will let water begin dripping out. The drain can also become detached from the pan, leaving a hole for the water to escape through. If the drain isn’t effectively removing water, it can cause algal growth in the drain, and this will lead to the pan overflowing. The AC has a limit switch that activates if the pan overflows, and you’ll see your thermostat screen go blank.

Only HVAC technicians can properly repair a broken condensate drain and pan. When you notice water dripping from your AC or the AC suddenly shuts off, call for our repair pros right away to take care of it.

First Choice Heating & Cooling is here to meet all your AC service needs. If your home had a voice … it would call First Choice!

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