The best portable swamp coolers, also known as evaporative coolers, are a great alternative to portable air conditioners in hot, dry climates. They aid fan cooling by adding moisture into the air, essentially producing a cool but more humid breeze. They tend to be more energy-efficient than air conditioners too and are a better choice for outdoor spaces.
The best portable swamp coolers produce air that feels like a fresh ocean breeze, without leaving water on your floors and furniture. They also have the added benefit of not using coolants or compressors, so they’re more eco-friendly.
When deciding on the best portable swamp cooler for you, the two most important pieces of information are the cooling area they can cover and CFM (cubic feet per minute) rating. The CFM is how much air the fan can move. The higher the CFM, the more powerful the evaporative coolers is. If you’re looking to use a portable swamp cooler in a large space, especially an outdoor space, you’ll need to choose a model with a larger cooling area. As these tend to be the more powerful models, they’re also more expensive. This is also a good reason to avoid choosing an overly powerful model for a small space, less powerful models will do a good job here and save you some money too.
Most of the best portable swamp coolers are suitable for both indoor and outdoor use but some have features more suited to one environment over another. Indoor portable swamp coolers tend to be more compact, with smaller tanks and features like remote controls and fan oscillation too. Outdoor models tend to be more powerful and are built for durability. Tanks sizes are larger and they usually have the ability to connect a hose too. If you want to bring them indoors make sure you keep the windows open and check manufacturer instructions for any extra considerations. They tend to be on the noisier side too, so you might want to check whether this might disrupt you indoors.
Below, you’ll find the best portable swamp cooler for you.
1. Frigidaire FEC1K7GA00: Best portable swamp cooler overall
The Frigidaire FEC1K7GA00 portable swamp cooler combines powerful performance and lightweight maneuverability for an evaporative cooler that is on the expensive side but is still $100 less than our second choice, the Honeywell CO610PM.
The 10.6 gallon tank is great for anyone looking to run the swamp cooler for long periods of time and, if even that isn’t enough, you can attach a hose for even longer continuous use. The three extra thick cooling pads allow the Frigidaire FEC1K7GA00 to efficiently produce cool air that is humid without leaving moisture on floors and furniture.
It can effectively cool both indoor and outdoor spaces up to 650 square feet and, along with the maneuverability, makes it a great option if you’re planning on shifting your evaporative cooler from space to space. It also comes with a one-year warranty, which is pretty standard for portable swamp coolers.
- Read our Frigidaire FEC1K7GA00 review
2. Honeywell CO610PM: Best portable swamp cooler for large spaces
At around $430, the Honeywell CO610PM is the most expensive portable swamp cooler on our list, but it’s also the most powerful. It has an impressive power output of 2100 cubic feet per minute and can cool areas up to 850 square feet in size. An evaporative cooler with that much power also needs a large tank so it doesn’t run out of water quickly, and the Honeywell CO610PM doesn’t disappoint. The 14-gallon tank means this evaporative cooler can run for hours before running out and if that still isn’t enough, you can connect a hose and run it all day.
This portable swamp cooler has been designed with outdoor spaces in mind, so it’s that bit more durable than others. It also uses a long-lasting copper motor, which outlasts standard fan motors. It’s not a bad looking evaporative cooler, but power and durability have definitely been prioritized over looks.
- Read our Honeywell CO610PM review
3. Hessaire MC18M: Best small portable swamp cooler
The Hessaire MC18M may be small, but it outperforms some of the larger portable swamp coolers on the market. For such a compact model, the 500 square foot cooling area is great but the 4.8 gallon is smaller than some of the other portable coolers on this list. It can handle around three to four hours of continuous use before it will need a top up, or you can attach a hose for longer use.
This portable swamp cooler from Hessaire has great energy efficiency, costing only $0.01 per hour to operate and the high-density evaporative material means it also has great evaporative efficiency. It’s largely suited to outdoor areas, but can be used indoors too with good ventilation.
There’s no LED display, but controls are simple and easy-to-use. Fan and pump speeds can be set and adjusted with a dial. The Hessaire MC18M is constructed of strong but lightweight ABS resin, so it’s durable too.
- Read our Hessaire MC18M review
4. NewAir AF-310 portable swamp cooler: Best budget portable swamp cooler
At a third of the price of the Honeywell CO610PM above, you can’t expect the NewAir AF-310 to measure-up power-wise, but it does a great job of cooling smaller spaces and contains a few extra features for greater control. A remote control is included so you can adjust settings from across the room, while the control panel itself is clear and easy-to-use.
The one-gallon tank size is definitely on the small side, but it does have a water-level detector to alert you when it is running low. On humid days, you can disable the evaporative functionality and just use it as a fan.
With a cooling area of 100 square feet, it’s not designed for large areas, but doesn’t overpower small rooms either. It’s not so noisy that it can’t be used in bedrooms at night, so it could be a good option for anyone who needs to cool their sleeping space at night.
- Read our NewAir AF-310 review
5. Honeywell CS10XE: Best portable swamp cooler for spot cooling
If you’re looking for a swamp cooler for small spaces, such as around your desk area, as opposed to for whole rooms, the Honeywell CS10XE is a great pick. It has a cooling range of 175 square feet and a CFM of 300-412, depending on the setting, so it doesn’t have a lot of power but it does have plenty of features that make it a great pick for small spaces.
The remote control, carbon dust filter, and low water alarm are nice features that you don’t often find included with other evaporative water coolers. The carbon filter cleans air by capturing particles that pass through it, while the low water alarm is particularly useful considering the water tank is on the small side.
It’s light on energy use too, costing only around $9 for typical use over the summer season. Even when running on the highest settings, it’s cheaper to run than an air conditioner.
- Read our Honeywell CS10XE review
What’s the difference between a swamp cooler and an air conditioner?
Swamp coolers, also known as evaporative coolers, work best in dry and warm climates as they work by adding moisture to the air that passes through it by pushing it over moistened pads, as well as cooling it. They need a fresh air supply to avoid overly saturated air, so you will usually need an open window or two when placed indoors.
Air conditioners pull air in before cooling it with a refrigerant and releasing it out again. Air conditioners often remove moisture from the air, so they’re better for more humid areas. They do need venting to get rid of warm air created during the cooling process, which can usually be done with a kit that attaches to a window. They tend to be more versatile than swamp coolers as features like digital thermostats, heating, and programmable timers are more common. However, portable air conditioners can’t be used outside like evaporative coolers can and they tend to use more energy too.
How much does a portable evaporative cooler cost?
The cost of a portable evaporative cooler varies depending on your cooling needs. You can easily spend $70 on a small unit for a dorm room or small office or pay up to $300 to $400 on a much larger one to cool garages, warehouses and even outdoor spaces. Keep in mind, though, that these are basically portable swamp coolers, so they are only effective in hot, dry climates. If you live in a humid environment then you may still use a swamp cooler for the hottest and driest part of the day and then switch on the air conditioner in the more humid mornings and evenings. Evaporative coolers cost much less to run than AC so if you want to save on your power bill then this is an option.
As most portable swamp cleaners need pads to work, it is also important to consider the ongoing cost of the pads. Prices for these start at around $20 and you'll need to change them annually or every three to five years depending on the model.
Why use a swamp cooler?
Portable evaporative coolers cost significantly less to install and operate than central air conditioning units, although they have much less cooling power. They’re lightweight and require only water and electricity to function, which means you can put them to use in your home or office. Since these units cool by adding moisture to the air, you should never use one alongside a traditional air conditioner, which cools by removing moisture. In shared spaces, these different types of coolers cancel each other out and waste energy. However you can turn one off and use the other, just don't use them at the same time.
How does a swamp cooler work?
A swamp cooler works by taking dry, hot air and cooling it by adding moisture to it by evaporating water stored in an attached tank. The dry air is filtered through a wet swamp cooler pad to add moisture. This air is then spread through the room using a fan or motor. This process is known as evaporative cooling.
How to choose a portable evaporative cooler
When looking to buy a portable swamp cooler, always consider the following:
Climate and swamp coolers
Evaporative cooling technology is most effective in hot, dry environments such as the Western U.S., and it doesn’t effectively lower temperatures in places with high humidity.
How energy efficient are evaporative coolers?
Since evaporative coolers don’t have compressors, their power consumption is significantly lower than that of a central air conditioner. On average, evaporative coolers can make the ambient temperature anywhere from 20 to 30 degrees cooler than outside air. These limitations mean evaporative coolers don’t offer the same comfort as portable air conditioners.
Weight and portability
Since portable swamp coolers are intended to cool one room at a time, you may need to purchase a unit that’s light enough to move around your house. More sizable units cool larger areas, but they can be much harder to move than their lightweight cousins. The best-designed heavyweight units have caster wheels that make them easy to reposition.
Size and effectiveness
For portable evaporative coolers, bigger isn’t necessarily better. At the same time, choosing a unit that’s not big enough can leave you overheated. Evaporative coolers’ cooling efficiency is rated in cubic feet per minute (CFM). All portable swamp coolers have CFM ratings, which makes it easy to figure out if a unit is powerful enough to cool a given area.
To pick the right size cooler for your room, you must first determine how many cubic feet you need to cool. This is done by multiplying an area’s square footage by the ceiling height. For example, a 250-square-foot room with an 8-foot ceiling has a cubic area of 2,000 feet (250 x 8 = 2,000). You then simply divide the cubic area in half (2,000 / 2 = 1,000) to find out how many cubic feet your evaporative cooler needs to be able to cool per minute. So, in this example, you would need a unit with a CFM rating of 1,000.
The best portable swamp coolers often come with extra features that make them more convenient and easy to use. Some models have timers, remote controls and automatic thermostats that turn the unit on or off depending on the room’s temperature. Others include oscillating fans to evenly distribute air, alarms that notify you if the unit is running low on water, and adjustable speeds for gradual or rapid cooling. Some portable evaporative coolers also double as ionizers that remove pollutant particles from the air.
Swamp coolers and poor warranty support
One of the most unfortunate things about portable evaporative coolers is the poor warranty support across every brand we evaluated. We did not find a single product that offers more than one year of warranty coverage.
We suspect poor warranties come mostly from the design of these units and the water they use for cooling. For example, although the design uses four simple components – a water pump, a fan, a cooling pad and a water tank – using these components causes a lot of wear and tear. Furthermore, dissolved minerals from your water supply will remain in the unit after the water itself evaporates, which makes it difficult to keep the unit clean and functioning properly in the long term.
You may still get multiple seasons of use from a portable evaporative cooler, but you may need to double down on maintenance tasks, such as replacing the cooling pad and occasionally removing hard-water deposits. Check the unit’s manual for additional maintenance instructions.
Do evaporative coolers need to be vented?
Yes, but not to the same extent as a portable air conditioner. While evaporative coolers don’t produce any waste heat that would warm up an unvented room, they can raise humidity to a point where the cooling effect is not as strong. This is the same reason why evaporative coolers aren’t effective outside of dry climates. As such, you should consider cracking one or two windows in your home to create a cross breeze so humidity levels don’t get too high.
At what humidity do evaporative coolers become ineffective?
The effectiveness of evaporative coolers depends on two factors: relative humidity levels and air temperature. In general, you can expect a temperature drop of 10 to 12 degrees as long as there isn’t more than 50 percent humidity in the air. That said, lower levels of humidity will give you much better performance. With an average humidity of 20 percent, for example, you can expect a temperature drop between 16 and 22 degrees. With regards to temperature, hot air can hold more moisture than cold air, allowing for greater cooling effectiveness, though this applies mainly to dry climates in places like the Western U.S., particularly Arizona, Nevada and Utah, where the hot air isn’t already saturated with moisture.
How to make my evaporative cooler colder?
There are several things you can do to help your portable evaporative cooler produce colder air:
- Soak the cooling pads before using the fan. It’s important to run the pump by itself for at least 10 minutes before using the fan, especially on hot days when the warm air might dry out the pads faster.
- Use cold water, but not too cold. The temperature of the water has some effect on how much cool, moist air an evaporative cooler produces. That said, if the water is too cold, it won’t evaporate as quickly, which can waste energy. On the other end of the spectrum, hot water might evaporate too quickly and could introduce some heat into the air. Because of this, you should use cold tap water in your portable swamp cooler, which is usually between 50 and 75 degrees.
- Use ice cubes for a temporary boost– While it’s true that you don’t want water that’s too cold, it can be useful to put some ice cubes in the water tank to help chill water that’s warmed up over time. However, avoid using ice water in your evaporative cooler otherwise.
- Use a dehumidifier. You can place a dehumidifier near the intake of a swamp cooler when it’s too hot to open the windows. This will help provide drier air to the swamp cooler and prevent humidity levels in the room from getting too high, although the extra energy cost might mean you'll be better off with an air conditioner instead.