Buying Tips For Portable Air Conditioners

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Tips for buying and sizing portable air conditioner units for your home or office.

While many people who live in hot humid parts of the country have either central air conditioning (AC) or window-mounted AC units, for some people this is not an option. If you are short on money or just want to spot cool a room in your house, a portable AC unit may be your best bet. There are many manufacturers and they can be purchased at home centers or department stores anywhere in the country. They are easy to operate and require a standard grounded 15-Amp receptacle and an operable window in which to mount an exhaust vent kit. This article will discuss a few models and options that are commonly found in portable AC units.

Window air conditioners might be rated at 10,000 BTU while a typical 2000 square foot house would have an air conditioning system from 48,000 to 60,000 BTU. Portable AC units range in size from about 7,000 BTU to 14,000 BTU. One ton of refrigeration is 12,000 BTU which can cool a 400 square foot room easily.

These units are also used to cool computer equipment in small office settings.


• 7,500 BTU: 150 square feet

• 9,000 BTU: 200 square feet

• 10,000 BTU: 250 square feet

• 12,000 BTU: 400 square feet

• 14,000 BTU: 420 square feet


The operation is the same as a window-mounted AC unit except that portable units have wheels and can be moved around. They have similar cooling capacities as window units.

All portable units must have the warm air coming of the condenser vented to the outside. This is accomplished by way of a flexible hose, or two on some models, that clips onto the back of the unit and to an adjustable plate that fits in most windows, even casement. If the unit will be a semi-permanent feature, you may want to install a dryer vent so that the unit can be vented through an exterior wall. The units are designed with a certain exhaust airflow so care should be taken to keep the hose transitions smooth and users should not add sections of exhaust hose unless it is an option from the manufacturer.

Typical Vent Assembly

Installing a Thru-wall Vent for Portable AC Units

1. Use a jigsaw to cut a 4-inch-diameter hole through an exterior wall.

2. Apply silicone caulk to rear flange on wall vent.

3. From outside, slide weather and bird proof wall vent through hole in wall; secure with stainless steel screws.

4. Twist and lock the flexible duct to the exhaust port on rear of AC unit.

5. Connect the duct end to the wall vent and seal with foil duct tape.

6. Test the unit operation and check for any leaks in the exhaust system.

Older units had a receiver bucket inside the housing where condensate was collected and had to be emptied periodically. Newer models use evaporation to get rid of the condensate that eliminates the need for emptying, but it also reduces the dehumidification of the room. I don’t particularly like this feature, but if you don’t have an easy way of getting rid of the condensate, this is a good option.

Portable AC Drain

Most manufacturers call this “Self Evaporating Technology.” During the cooling process, water is extracted from the air by the evaporator coil. Most of this water is then recycled and used to cool the unit and make it run more efficiently. Approximately 65 to 70% of water condensed is evaporated out with the exhaust air, reducing the hassle of emptying the water tank constantly. Units will still come with a built-in water tank that is not removable, with a drain outlet and a water tube. When the tank fills, the compressor stops operating and the power light will flash. This indicates that the tank should be emptied. Follow the process in the owner’s manual.

Most of the portable units now come with a remote control for ease of use. These control all of the operations on the unit and use AA or AAA batteries that need to be replaced occasionally. Many units also come equipped with timers and can be set to turn off from 1 to 12 hours.

Units can also come with operable louvers that swing to move the air around the room, similar to an oscillating fan. Most units have 3-speed fans to control the airflow.

All units come with washable mesh filters that need to be cleaned periodically with a hose, in a sink, or in your dishwasher.


Friedrich ZoneAire P12A Portable Air Conditioner

Cooling Rating: 11,500 BTU/hr

EER: 8.9

Cooling Amps :12

Plug Face: 5-15P Volts - 115

Circuit Breaker Rating : 125V-15A


Width: 19 1/4 in.

Depth: 15 1/2 in.

Height: 33 1/2 in.

Net Weight - 86 pounds

Unit has no water bucket, providing all the cooling benefits of a portable unit while eliminating the need for emptying one every few hours.

LG LP1200 Portable Air Conditioner

Swing Louvers: 2-Way

Filter: Reusable

Air Flow: 300 CFM

Cooling Capacity: 12000 BTU/hr

Energy Efficiency Rating: 9 EER

Fan Speeds (Cooling): 3

Cooling Watts: 1340

Voltage: 115

Cooling Amps: 12


Width: 19.69 in.

Depth: 18.88 in.

Height: 33.44 in.

Warranty: 5 Years

Unit has no water bucket, providing all the cooling benefits of a portable unit while eliminating the need for emptying one every few hours.

Other manufacturers are Sharp, DeLonghi, GE, and others. You can read reviews online at Consumer Reports,, or

1 comment

carol roach
Posted on Apr 29, 2010