This is what we’ve found when testing six portable air conditioning units that, in spite of their promises, were barely able to lower the room temperature beyond stifling hot, much less to the upper threshold of inside comfort levels which is about 78 degrees.
Units of this type are designed for use in homes that have insufficient window configurations for window units or in which building rules and regulations make it impossible to use window designs.
Purchasing one of these units, however, is not a worthwhile compromise given the fact that this equipment is usually noisy, big, costly and heavy on energy use.
There are a lot of retailers who report having a number of portable models returned each year because consumers were dissatisfied.
How these function. These are far different from window air conditioner units in that all of the components are directly inside of the space that you’re cooling.
This is why these models are noisier and less efficient: the portable unit uses cool air from the room to keep the condenser coil cool and it also uses an ineffective exhaust hose that looks like a dryer vent to exhaust warm air. This results in negative air pressure that winds up drawing hot air in from the surrounding rooms.
How portable are these designs? There is some debate over the portability of these units because once you have connected the exhaust hose to the window venting kit, you won’t really want to move this equipment around, especially when it can weigh up to 80 pounds.
Something that the best portable air conditioner reviews will tell you is that even though these units are on casters, they are not easy to roll across carpets or over any raised thresholds.
They also require a considerable amount of space – their hoses can measure up to 7 feet in length and the unit has to be kept back from furniture and walls so that the air flow isn’t blocked.
How we perform our tests. For our reviews, we calculated the length of time it took for a unit to lower the room temperature for its claimed sized to 75 degrees from 90. Not many of these made it to just 80 degrees after a full 100 minutes of operation.
None of these are on our list of recommended products, but as a last resort, check out the Honeywell MN10CES[WW] which has a fairly reasonable price of $400. Although it provides average cooling, it did well in our simulation of brownout conditions, as did four of the other models.