Portable Mobile Room Air Conditioner in front of brick wall

One of the key maintenance procedures for a portable air conditioner is regularly draining it. The operation of air conditioners includes a condensation process that causes water to accumulate in the unit. Therefore, to keep it operating optimally, you need to know how to drain a portable air conditioner and you need to do it regularly.

There are three main methods to learn when it comes to how to drain a portable air conditioner.  These methods can be done without a house, with a hose, and using a pump.

Below is a detailed look at each method and the steps involved.

3 Ways How to Drain a Portable Air Conditioner

How to Drain a Portable Air Conditioner Without a Hose

Typically, portable air conditioners do not come with a drain hose. Therefore, you have to drain the unit manually. You can either move the air conditioner outdoors, drain the water to the ground, or place a bucket underneath. You could also use a pan.


  1. Power off and unplug the portable air conditioner
  2. Take a stool and place the unit on top.
  3. Place a bucket below the unit with the bottom edge aligned with the inner edge of the bucket.
  4. If there are louvers below the top drain plug, lay transparent kitchen paper over them to prevent water from splashing into the interior components.
  5. Open the top drain plug and allow water to flow into the bucket until all the water is drained. Close the plug.
  6. Open the bottom plug and let the water flow into the bucket until it stops coming out completely.
  7. You may slant the portable air conditioner slightly towards the bucket to ensure all the water drains out. However, be careful to prevent the unit from falling off the stool.
  8. When you finish draining, remove the paper. Then, plug in the unit and power it on.

How to Drain a Portable Air Conditioner With a Hose

Draining a portable water conditioner with a hose is a convenient method to continuously drain the unit. This method works best if you live in highly humid and extremely hot areas, which causes the air conditioner to accumulate water fast. However, it relies on gravity, and you need access to a nearby floor drain.

how to drain a portable air conditioner


  1. Turn off the unit and then plug it out from the wall power outlet.
  2. Identify the drain plugs at the back of the unit. Some portable air conditioners have one drain line at the bottom, while others have two, including a top one. If you have multiple drain line lines, you will need to install a drain hose on each port.
  3. Get a drain hose that is compatible with the size of your unit’s drain line. Drain hoses are readily available at an affordable price range in your local stores or online stores.
  4. Open the drain plug and insert the drain hose on the unit’s drain line. It should fit snugly to prevent leakage. You may reinforce the fit with a zip tie.
  5. Insert the end of the drain hose into a floor drain. Gravity will cause the water to automatically drain from the air conditioner to the floor drain.
  6. If your unit has multiple drain lines, repeat steps 3, 4, and 5 above for the other ports.
  7. Once done, plug the unit back and power it on to resume operation.

How to Drain a Portable Air Conditioner with a Condensate Pump

A condensate pump lets you drain your air conditioner continuously in areas where you cannot leverage gravity. You can use it to drain the unit through a window or a sink. It is a more expensive option than using a hose or no hose, but it works effectively.

A condensate pump comprises three main parts: the drain line attached to the air conditioner, the pumping unit, and the open-end drain line. The water is drained to a floor drain or outside using the pump. Usually, a condensate pump comes as a pumping unit and has separate tubing you cut and attach.

The condensate pump has a water reservoir where water collects through gravity from the air conditioner. It turns on automatically when water reaches a certain level to drain and then turns off when most of the water has finished draining.

how to drain a portable air conditioner 


  1. Turn off the portable unit and then unplug it from the wall power outlet
  2. Identify a location for your pump. It should be positioned lower than the air conditioner’s drain line
  3. Cut the appropriate length of tubing. Attach it to the air conditioner’s drain port and the other end to the pipe
  4. Cut another piece of tubing. Connect one end to the pump’s check valve and the other end to the point where you want the water to drain

How Often Should You Drain a Portable Air Conditioner?

The frequency of draining your portable AC unit depends on factors such as:

  • Humidity level in the immediate environment. The higher the humidity level, the more water will accumulate in the system during the condensation process. Therefore, the more frequently you will need to drain the portable air conditioner.
  • Surrounding temperatures. When the surrounding temperatures are extremely high, the unit works harder to cool the air. As such, it produces more condensation water as it has to cool off larger volumes of air.
  • How Recently You Installed the Air Conditioner. When you install a portable air conditioner in a room for the first time, it goes full-on to dehumidify the entire room. Therefore, it may release more water in the first few days, but it will slow down over time.

What Happens if You Do Not Drain Your Portable Air Conditioner

If you do not drain your AC unit, water will continue to collect to a level where the entire system shuts down. It does not turn on until all the water has drained.

Some units present with a warning indicator light while others simply shut off. Also, if the condensate tank has a faulty float switch, the unit may leak or overflow.


When learning how to drain a portable air conditioner, remember there are three main ways you can do so: into a pan or bucket, using a hose, or a pump. As discussed above, each method is appropriate in specific settings, and each has its pros and cons. Whichever method you choose, the goal is to keep the unit drained for optimal operating efficiency.