For some, a portable air conditioner may be the only way to get relief from summer heat and humidity. A portable air conditioner can also cut your energy use, reduce your carbon footprint and solve cooling problems in your home. Portable air conditioners aren’t quite as effective as wall or window units, so you need to choose carefully. Keep your expectations reasonable and let Pronto’s Portable Air Conditioner Buying Guide steer you to the portable that’s best for your needs.
Portable air conditioners may be the only choice for apartments, and they provide excellent supplemental cooling in homes with central air.
Start with a general rule of 12,000 BTUs per hour, equal to one ton, for a 500-square foot room for a portable air conditioner that will supplement central air conditioning. For standalone use, high ceilings or a space with poor insulation or window seams, increase the BTUs by 20% to 30% over the standard 12,000 BTUs for 500-square feet.
Look for digital cooling controls and multiple fan speeds that provide better energy efficiency and let you reduce fan noise while you’re sleeping.
It’s worth investing in an evaporating or dripless portable air conditioner for greater ease of use. Otherwise, look for water venting through the hose or deep drip pans that slide out easily.
Check the energy efficiency rating (EE) to find the most power-friendly portable air conditioner. Models with Energy Star certification are at least 10 times more efficient than comparable portable air conditioners.
Short for British Thermal Units, a measurement of the ability to raise or lower one pound of water one degree Farenheit. Higher BTUs indicate more cooling capacity for a portable air conditioner.
Also known as evaporating, a portable air conditioner that removes condensation by heating accumulated water until it turns to vapor.
A bin at the bottom of a portable air conditioner that collects the condensation formed during cooling. Drip pans need to be removed and emptied periodically. The size of the drip pan and the amount of cooling needed determines the frequency.
Short for Energy Efficiency Rating, this measures the power consumption of a portable air conditioner by dividing its BTUs per hour by the amount of power consumed per hour. Higher numbers equal greater energy efficiency.
Also known as a room air conditioner, a self-contained cooling unit that vents hot air through an attached hose and that can travel from room to room, typically on casters.
A standard measurement of cooling power equivalent to 12,000 BTUs. A rule of thumb for air conditioners is to have one ton of cooling per 500 square feet of floor space.
An exhaust duct that travels outdoors from a portable air conditioner. The hose sends room heat outside and needs to be mounted through a window. Some portable air conditioners also discharge collected water through the hose.
A portable air conditioner, also known as a room air conditioner, is a self-contained unit that provides cooling. Like window and wall models, portable air conditioners cool by using a fan to draw air past a coil filled with pressurized refrigerant gas. As the air passes the coil, hot air is pulled out and replaced with cold air.
For a portable air conditioner to be effective, hot air must be vented outside of a sealed room. Most portables have a vent hose that installs in a window to push out hot air. It’s best to take the term “portable” with a grain of salt; portable air conditioners can weigh from 50 to 90 pounds, but these self-contained units move on casters, making it easy to push them from room to room.
Portable air conditioners are not as effective at general cooling as window- or wall-mounted air conditioners, typically because they’re the only source of cooling in a hot home. If you live in an apartment, have windows that prevent the installation of an air conditioner or have hot spots in a home with central cooling, you’ll benefit the most from a portable air conditioner. If you need significant cooling, check out Pronto’s Air Conditioner Buying Guide.
All air conditioners are rated for cooling in terms of British Thermal Units (BTUs) per hour. A single BTU is a measurement of a portable air conditioner’s ability to lower the temperature of a pound of water by one degree Farenheit. More BTUs equals more cooling power, but also more energy consumption.
To determine the amount of cooling needed, you should convert BTUs to tons at a rate of 12,000 BTUs per ton. In other words, a 12,000 BTU air conditioner creates one ton of cold air per hour, enough to cool a 500-square-foot room. If you’re using a portable air conditioner to supplement cooling from a central system, you can stick with this standard measurements. But if the portable air conditioner is working alone, either in an apartment or a home that lacks other air conditioning, you’ll need 20% to 30% more BTUs per 500 square feet for effective cooling.
There are many variables to consider in choosing the power of a portable air conditioner. Consider the room size, its location in the house (heat rises, so you’ll need more cooling on upper floors), insulation thickness and the quality of window seals. Ceiling height also plays a factor, as BTU and ton ratings assume a standard eight-foot ceiling. When it comes to portable air conditioners, it’s a good idea to get more than the minimum needed for the best cooling.
Gone are the days of twisting a knob all the way to the right for maximum cold. Most portable air conditioners now offer digital controls that let you set a precise temperature, a feature worth paying for because it gives you precise climate control and regulates energy consumption. Some portable air conditioners include remote controls, so you don’t have to break a sweat walking across the room to make adjustments.
Adjustable fan speeds are another feature that adds to the efficiency of portable air conditioners. Most portables offer two or three fan speeds and few manufacturers charge more for this feature. A little comparison shopping will yield a portable air conditioner with the fan settings you desire.
Variable fan speeds also let you control noise, which is a chief concern if you’ll be using a portable air conditioner where you sleep. Portable air conditioners bring all the cooling elements into the room, making it worthwhile to read online comments about noise when you’re shopping.
When hot air meets cold air, condensation occurs, creating water. Most portable air conditioners need a way to get rid of condensation, though some newer models can evaporate the water they create. Known as evaporating or dripless portable air conditioners, these models come at premium prices but may be worth it for ease of use.
Most portable air conditioners collect condensation in a drip pan that must be removed and emptied on a regular basis. Look for deep drip pans that slide out easily to prevent spills and eliminate the need for 3 AM emptying on hot nights.
Alternatively, you can choose a portable air conditioner that disposes of water through its vent hose. Although this feature eliminates the need to empty drip pans, it limits the placement of the portable air conditioner as you’ll need the hose to have a short downhill trip outdoors to prevent water from collecting in the hose.
Portable air conditioners have filters that prevent dust and other airborne particles from clogging their fans. Most filters are for the portable air conditioner’s benefit—they won’t clean the air, they just keep dust from clogging moving parts. Some portables can use air-cleaning filters, but if clean air is a top concern, you’re usually better off with a separate air filtration system.
Filters need to be cleaned or replaced periodically. The best value is a portable air conditioner with a reusable filter that can be removed, cleaned and replaced. This provides a lower lifetime ownership cost than a portable air conditioner with disposable filters.
Most people think of air conditioners as electricity hogs. In reality, a portable air conditioner can reduce your energy use by cutting back on whole-home cooling. Portable air conditioners let you turn the main thermostat up while keeping cool in a single room.
To get the best balance of electricity consumption and cooling, look at a portable air conditioner’s energy efficiency rating (EER), which divides a unit’s BTUs per hour by the amount of electricity consumed. Higher EERs deliver more energy efficiency. A portable air conditioner with an Energy Star certification is at least 10 times more efficient than comparable models. Remember, too, that raising the thermostat and slowing down the fan will provide the greatest energy efficiency.