Why Is My Air Conditioner Not Dripping/Draining Water?

When air passes through an AC’s evaporator coils, it condenses and loses moisture. This moisture drips down from your AC’s drain pipe. So, what does it mean when there’s no water dripping down?

The air conditioner doesn’t drain water for several reasons, such as a clogged drainpipe, dirty evaporator coil, or improper drain line installation. Proper and regular cleaning of your AC unit can solve the problem. 

When the air conditioner does not drain water, it can affect the machine’s efficiency. Let’s keep reading the article to understand why your AC does not drain water and how to fix the problem.

Here’s Why Your Air Conditioner Isn’t Draining

The reason can be as simple as a clogged drainpipe. However, there may be other issues that require an expert’s help. 

Let’s see some other reasons why you can’t see any water dripping out of the drainpipe:

The Drainpipe Factor

As mentioned, dirt, algae, or mold can clog the drain pipe that does not let the water drain. The most common reason for a clogged pipe is the water itself.

The pipes are usually out in the open, where dust can enter them. So, when the dust and debris enter the pipe, they can clog it. A clogged pipe does not let the water pass through. The stagnant water receives sunlight and other nutrients that promote algae growth. This is how the drainpipe becomes completely clogged. 

Another reason could be a poorly connected drainpipe. The water will leak and not drain if the drainpipe and condensate pipe are not well connected.

Read: Why Window Air Conditioner All Lights Flashing And Beeping

Poor Condensate Line Installation

Another reason could be the poor installation of the condensate pipe. The line starts from the internal unit and goes out from the outer unit. When the drain line is clean, but the water doesn’t drip from the drainpipe, it may be due to the poor installation of the drainpipe. 

Improper installation can cause water leakage preventing the water from reaching the drainpipe. 

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Read: Why Air Conditioner Is Not Heating?

A Broken Condensate Line

When mold and installation aren’t the problems, it could be a broken condensate line. 

The breakage mostly happens when the air conditioner has a plastic pipe. The water can leak through cracks in the pipe before reaching the drain line’s outer end.  

In case of cracks or breakage, you may have to replace the pipe altogether. 

Read: Why Air Conditioner Not Blowing Cold Air But Running?

A Damaged Evaporator Coil

The evaporator coil absorbs moisture as vapors from the air using a refrigerant. The coil condenses the water vapors into liquid, which drips out of the drainpipe. When the evaporator coil does not work correctly, it fails to drain the water out. 

The coil malfunctions due to several reasons:

  • Dirt accumulation on the coil creates insulation, preventing adequate heat absorption.  
  • The drainpipe is clogged. It prevents the coils from condensing the water vapors, so the vapors freeze instead. When the vapors freeze, there is no water and hence no dripping. 
  • Corrosion can also create small holes or leaks in the evaporator coil, disrupting the condensation process. It usually happens when the moisture reacts with the chemicals found in the air inside the room. 

Read: Why Air Conditioner Heat Mode Not Working?

A Dirty Air Filter

There is no rocket science here. A dirty filter will not let the air pass through. So, when the air cannot pass through filters or minimal air passes, the coils can freeze, preventing condensation. When there isn’t enough condensation, the water does not drip out of the drainpipe. 

Air filters get dirty when they trap dust particles and other elements in the air inside the room or house. This clogs the filter, so you must keep them clean

What Happens When the Air Conditioner Doesn’t Drain Water?

If your air conditioner isn’t draining water from the back, it means it’s holding it in somewhere else. Stagnant water can cause mold in the unit, leading to an unhealthy bacteria buildup. 

Here are some problems you may face when your AC stops draining water.

More Humidity 

Poor water drainage can also affect your air conditioner’s efficiency. When the moisture or water cannot find the right exit, the air conditioner can release it inside, increasing your room’s humidity levels. This happens when the air conditioner retains more moisture than it can drain. 

It can also damage your walls, window frames, or whatever is under the unit. 

Air Conditioner Shut-Down

When the water cannot exit through the drainpipe, it accumulates in the AC’s water reservoir or drip pan. This is a common problem in portable air conditioners. Most of them shut down automatically when their reservoir fills up. The older models may malfunction. 

You must empty the drip pan regularly to keep the AC working, which is nothing but a hassle. 

Read: Why Does Air Conditioner Run At The Same Time As A Furnace?

How To Fix the Problem?

You can fix the water drainage problem if it’s just the drainpipe or the air filter. However, you may have to call an expert for more complex issues, such as the evaporator coil. 

Clean the Drainpipe

The best way is to clean the drainpipe regularly so it does not become the breeding ground for algae and mold. Cleaning the drainpipe is not too difficult, and you can do it yourself.

  1. First, you must switch the air conditioner off by turning its main power supply off.  
  2. Next, place a bucket under the drainpipe to avoid making a mess.
  3. Locate the point where the pipe connects with the drain line. You can take the pipe out from there and start cleaning. 
  4. Use a wire or pipe brush to clean the pipe from the inside. 
  5. Next, make a cleaning solution. You could mix bleach and water or use vinegar.
  6. Pour the mixture into the drainpipe and wait for 20 to 30 minutes. 
  7. Use lukewarm water to clean the pipe once more.
  8. Next, connect the pipe to the drain line and turn the AC on to see if the water is draining. 

Keep the Evaporator Coil Clean

Next comes the evaporator coil. Once the coil malfunctions, you may have to call in an expert. However, you can prevent damage by keeping the air filters clean. It will allow enough warm air to pass through, and the coils will not freeze. It’s good to clean the air filters regularly.

You can also clean the coils yourself: 

  1. First, open the air conditioner unit and locate the evaporator coils. 
  2. You need a coil cleaner for cleaning. You can make this cleaner at home by mixing detergent and water for DIY cleaning and put the mixture in a spray bottle. 
  3. Next, spray the coils. You must keep the spray light so it doesn’t have too much force. A forceful spray can damage the coils. The liquid should run down into the drip pan. 
  4. Let the coil dry after spraying. 
  5. Now, use a brush to clean dirt and debris but don’t brush too harshly. Rinse the brush between strokes to keep it clean. Brushing takes away stubborn dirt and residue.
  6. Spray the coils once more and let the coil dry.
  7. Close the coil panel after cleaning. 


Water dripping out of the drainpipe is a good sign. It shows that the air conditioner is efficiently cooling the room. However, you must ensure that the AC unit is draining, not too little or too much water. In both cases, something can be wrong with your air conditioner. The problem can be as simple as a clogged drain pipe or a little more complicated like a faulty evaporator coil.