How Long Can You Run a Portable Air Conditioner Continuously?

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For the most part, you can run your portable air conditioner continuously without any issues. As long as you regularly empty the condensate tank and clean the air filters, your portable AC unit should be able to run all season long without having to turn it off. 

Of course, various factors affect your air conditioner, and keeping it running smoothly without damaging it, is essential. To learn the best practices and the answer to your question, “how long can you run a portable air conditioner continuously,” continue reading!

a person setting up a portable air conditioner

How Often Should You Drain a Portable Air Conditioner?

Regular maintenance is necessary to keep your portable air conditioner cooling your home for the entire summer season. A big part of this maintenance involves emptying the condensate tank. 

But how often you have to empty the condensate tank depends on the humidity where you live

For instance, if you live in a dry area like Arizona, you will have to drain your portable air conditioner less often. This is because the water that fills the tank comes from cooling warm, humid air. And dry air has very low humidity.  

However, if you live in a humid climate (like Florida), you’ll have to drain the air conditioner way more frequently. Depending on the humidity levels and the size of the tank, you may have to empty the unit as often as every few hours. 

Note: Air conditioners produce water as a byproduct as they cool the warm air in your home. As the air cools, water precipitates out of the air and collects in the AC’s condensate tank. This is great for dehumidifying the air in your home but not so great if you forget to empty the tank. 

Humidity may be the result of internal or external factors. For example, showering, cooking, or a large group of people can cause the humidity level to rise. 

External factors primarily fall to the outdoor climate. If the weather is hot and humid, the air conditioner will produce water as it cools and dehumidifies the warm, moist air. 

What Happens if You Don’t Drain it? 

picture showing the back panel of hOmeLabs portable air conditioner

To stay in the green with your portable air conditioner, you need to drain it. If you don’t, there are a few things that may happen. 

The unit will shut off and not turn back on. This is the most common outcome when you don’t drain the condensate tank. Most portable AC models, like the hOmeLabs 14000 BTU portable air conditioner, have a built-in float switch, which turns off the unit if the condensate tank fills with water. 

If the unit has a full tank, it will usually notify you via the indicator light or audible alarm.

The condensate tank could overflow if the float switch fails. This creates a significant problem since it could lead to water damage in your home. 

Additionally, mold can grow in your condensate tank. Although many people don’t consider this a possibility in a portable air conditioner, it can happen

Note: The chances of mold growing in the unit are slim if you empty it often. But, if you turn it off and let water sit in it for a long time, mold or mildew can grow.  So, remember to empty the tank before storing it for the winter. 

Consider a Portable AC Unit with Continuous Drainage 

a portable AC unit with continuous drainage hose

If you live in a humid climate, run your portable air conditioner continuously, or don’t like the hassle of lugging a water tank to a drain multiple times a day, you may want to consider investing in a unit with continuous drainage. 

Note: When you set up continuous drainage with your portable AC unit, you will never have to empty the tank again! 

So, how does continuous drainage work? 

Continuous drainage works via a drain hose. One side of the hose attaches to the condensate tank, and the other side feeds to a drain. Alternatively, you could direct the hose outside to drain. Make sure it drains at least six feet away from your house. 

Note: While you don’t need to worry about regularly draining the tank, continue to keep an eye on it. The air conditioner’s inside will still be slightly wet from the condensate, so watch out for mold and ensure you clean the filters at least once per month. 

Why the Right Size Portable AC Unit is Important

Correctly sizing your portable air conditioner is critical to making your space cool and comfortable. 

If you purchase a unit that is too small, it will constantly run and might never reach your desired temperature. This will drive up your energy costs exponentially.

On the other hand, if the unit is too large for the space, it could short cycle. While this might not seem like a big deal, it is. It results in:

  • High energy consumption
  • Poor cooling performance
  • Struggle to remove humidity from your home
  • Air conditioner will turn on and off repeatedly
  • Balmy, humid environment because short, rapid cycles aren’t long enough for the system to remove humidity from the air. 
  • Increases wear and tear on the AC unit, leading to a higher frequency of equipment failure and costly repairs

Since buying a portable air conditioner that is either too small or too large can cause issues, purchasing a correctly sized unit is essential. The standard rule for portable air conditioner sizing is 20 BTU per square foot of cooling space

Info: Several factors may affect the ideal system size, including the number of doors and windows, ceiling height, and insulation quality. However, you can easily calculate a generic idea of what size of portable air conditioner you need based on the 20 BTU per square foot rule. 

If you’re unsure which size is best for your home, reach out to a portable air conditioner dealer or HVAC technician for assistance. 

How Often Should You Clean Your Portable Air Conditioner Filters?

a person washing a portable air conditioner’s filter

When you run your portable air conditioner continuously, you need to keep an eye on the filters. Generally, you should clean the filters at least once per month. Depending on outdoor air quality in your area and inside your home, you may need to clean the filter more frequently. 

Note: While it’s imperative to clean the filter in your portable air conditioner at least once per month, you also need to clean it even if you don’t run the unit constantly. 

A good AC tip is to keep your filter clean since it will improve your indoor air quality. 

How To Set Up Continuous Drain For A Portable Air Conditioner

a woman installing the continuous drain for a portable ac

Setting up a continuous drain for your portable air conditioner doesn’t take long.

Here’s what you need to do to set up constant, gravity-fed drainage:

  1. Start by draining the condensate tank according to the manufacturer’s instructions. Usually, you just have to pour the bucket down the drain. But sometimes, you will have to let some excess water drain out the bottom after removing a plug. 
  2. Measure the drain port opening to the tank. 
  3. Purchase a hose with the appropriate thread type. In some cases, a regular garden hose is sufficient in place of a drain hose. Other times, the portable AC unit will have a barb connection for push-on tubing. Consult the AC unit’s instruction manual to determine the correct size hose (or tube) you need. 
  4. Determine where you want the water to drain. 
  5. Run your drain hose to this location, ensuring the hose remains as straight as possible and has no kinks. If possible, angle the hose downwards since the drainage is facilitated by gravity.

Screw hose clamps can be a helpful tool in ensuring a water-tight seal at the hose end. In addition, ensure you purchase a sturdy hose that stretches long enough to reach from the unit to the proper drainage area. 

Did you Know: That battery-powered air conditioners are available?


So, how long can you run a portable air conditioner continuously? You can run portable air conditioners indefinitely, provided you empty the condensate tank when it is full and clean the filter every month or so. Setting up the portable AC unit with continuous drainage makes your life easier and comes in handy in the sweltering summer months. 

All in all, portable AC units can usually run continuously without a hitch, but it’s essential to keep up on maintenance.

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Jonathon Jachura
Jonathon is a mechanical engineer with over ten years of experience in the HVAC industry. He has hands-on experience with all types of HVAC systems.

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