Self Evaporating Portable ACs

Most portable air conditioners need to be drained periodically of the water that condenses.

Self evaporating portable A/C's are different because they don't need draining at all!

Why is this seemingly insignificant point of any consequence? Why would you want to buy one of these more expensive cooling devices anyway?

Let's look at what they are and how they work to see what their advantages are over their cheaper counterparts.

Why Do Portable A/C's Need Draining?

portable air conditioner drain hoseAs I mentioned in the introduction to this article, most portable AC units need to be drained every now and then. That happens because moisture is condensed out of the hot, humid air in a room during the process that chills it and returns it nice and cold.

That condensation forms ever larger droplets that drip down into a catchment area that when full will either sound an alarm of simply shut off the machine.

Naturally, a turned off cooler isn't much use when it's hot.

To keep it running when you need it most, that collected water must be drained off. Fortunately, portable air conditioners are fitted with a drain hose at the bottom, usually round the back that you simply pull out, place the end in a tray or bucket and open the plug.

A small amount of water will drain out, after which you can replace the plug, push back the hose and restart the unit. Cold air again!

Oh, and don't forget to empty the bucket!

What is a Self Evaporating Air Conditioner?

Instead of having all that hassle, self evaporating models have been created to do away with the need to drain water along with some clever tricks to get more from the cooling process than regular AC units.

First of all, new technology is incorporated into the refrigeration process that reuses the condensed moisture to assist in cooling the air. After it has been used and naturally heated up, it is re-evaporated and expelled through the exhaust vent hose out the back, through the window vent to the outside.

That, in a nutshell is what this type of cooler is and what it does. What about the advantages over the regular models?

Benefits of Fully Self Evaporating Air Conditioners

There are two main benefits that come directly from the way they reuse the condensed moisture:

  1. No more hassle with draining any collected water
  2. Better efficiency means better energy economy, means it costs less to run

self evaporating portable air conditionersYou may not think that not having to empty a full drain collector is a big deal. At least not until you've had your cooler shut off on the hottest day and you're trying to figure out how to get it to work again.

Next, after searching around to find the user manual and reading about it, you have to fiddle around with a drain hose and a bucket or tray to empty it.

All of a sudden, it's a big deal!

Getting better energy economy from a cooler is a real big deal, since they use a lot of electricity anyway. Anything that'll help them use a little less is a good thing.

The energy saving is not massive, but even a little will make a difference when your next electricity bill arrives.

No More Negative Pressure

There is another advantage to these models. They generally come with two vent hoses (often referred to as "dual hose air conditioners") and I'll explain why that is.

AC units that have a single vent hose use it only for exhausting hot, moist air out of the unit and out of the room through the window vent.

They suck in warm air from the room, process it and pump out cold air out the front, while the hot air they produce as a by product of the refrigeration process goes out the back.

As the air flow is kind of one way, it creates negative air pressure inside the room, which is often closed up to prevent more warm air from getting in and making the cooler work harder to keep it cool.

Unfortunately, that negative pressure needs to find its own balance. Nature hates a vacuum, after all. So warm air from outside will find a way in through masonry cracks and gaps in door frames and windows even when you can't see them.

Dual hose coolers stop that all happening by using the second vent hose to bring in air from outside to assist with the cooling process. So it actually has two inlet points, one taking air from outside, the other taking air from the room.

No negative pressure means no hot air will get sucked into the room from outside. That means the unit runs more efficiently without having to cool the extra warm air.

Want to Buy a Self Evaporating Portable Air Conditioner?

Now that you know some more about these very attractive free standing cooling devices that you'll never need to put up with the hassle of draining, do you want to buy one?

Whether you do or you don't, it can't hurt to take a closer look at one or two of the top models that are currently on sale online at Amazon. Here are two of my personal favorite models with a short description, an image and a direct link to their respective Amazon pages so you can read all about them there:

Note: As an Amazon Associate I earn from qualifying purchases.

Whynter ARC-14S

My top pick free standing air conditioner is the powerful, efficient, dual hose Whynter ARC-14S.

It's one of the most popular models of its kind on Amazon, as you'll see from the 2,500+ reviews left by purchasers. And with an overall four star rating, that's a very good indicator this model is adored by its owners!


With dual hoses to improve efficiency and increase air throughput, this popular cooling appliance cools a room up to 500 sq ft faster and more economically than single-hose models.

It has a massive dehumidifying capacity of removing up to 71 pints of moisture per day from the air.

Operating noise levels are relatively low for a high power machine such as this at a max 56 dBA when running on full power. The unit also features eco-friendly CFC free green R-32 refrigerant along with RoHS compliant components.


Being a portable AC, it requires fixing a window kit to connect the two exhaust hoses to. Two hoses can look less appealing than a single hose, but one of two hoses is a necessary feature of all portable air conditioning units.

The extra cooling power also comes with another downside, being the weight. This model weighs in at 73 pounds.

If you want plenty of cooling power without the high electricity usage of some models, the AR14S is a great choice of eco-friendliness and low power consumption relative to its high cooling rating.

Click/tap the image above to visit Amazon for full details.

Whynter ARC-110WD

This is an eco-friendly, lower powered air conditioner that still packs a powerful cooling punch with its 11,000 BTU rating.

Dual hose operation means much greater efficiency when transferring heat into cold air without internal air pressure problems that single hose units can create.

Of course one of the most important features is the patented advance auto-drain technology that sets this device above the rest. It recycles the moisture that's collected during cooling and uses it to aid the production of cool air, increasing efficiency and reducing energy wastage.

The moisture recycling aspect works best in areas with lower humidity as there's less moisture to process, but it will provide plenty of cold air in all atmospheric conditions since it also acts as a dehumidifier while cooling.

That makes it perfect for use at home, in the work place and even in moisture-sensitive computer rooms and electrical wiring closets as well as workshop areas with machinery.

Click on the image or the link below it to visit the model's page at Amazon to see the full feature list and details for yourself!

Honeywell MN4CFSBB9

An honorable mention goes to the Honeywell 14,000 btu portable cooler with its auto-evaporation system that allows for continuous operation without the need to drain water or empty a bucket.

It's another popular brand model with a name most people already know and comes with a good many 4 or 5 star reviews on Amazon.

The main reason I didn't put this model first is it only has a single hose for ventillation and hot air exhaust, unlike the Whynter above that has dual hoses. That means it is not as efficient, which I personally place a high emphasis on.

The number of hoses aside, this unit does a great job of cooling the intended space of up to 550 square feet and acts as both air cooler and dehumidifier with a fan-only function if you need it.

It also comes with all the attachments you need to hook the hose up to a convenient window opening, which is fairly easy to install yourself.

Click on the image to the right or the direct link below it to view this model at Amazon and see it for yourself!

All Good in the End

self evaporating portable acSo you see, there are three main advantages to buying a dual hose, fully self evaporating portable air conditioner instead of trying to save a few dollars to get a cheaper, single hose alternative.

That's if you're in need of a portable AC anyway. Oh, and also if your local climate is pretty humid in summer as most the country tends to be.

Of course, if you're lucky enough to live in a really dry climate such as is common in the south-western states and dessert areas, you can save a lot of money on running costs by opting for a swamp cooler. But that's a topic for another article!

External resources: If this is a subject that really interests you, there is a lot more information available to be researched on ventless evaporative coolers here: and also here: