Five Common Cooling Mistakes

Portable coolers such as portable air conditioners and swamp coolers are useful in a wide range of situations.  Because they are compact and mobile, they are great alternatives to window or wall air conditioners or even as a supplement to central cooling units.  Portable coolers are suitable for apartment buildings that do not permit window units or for homes with windows that cannot accommodate permanently installed air conditioners, and in many cases, they can be much more cost effective to run when compared to central systems. 

While portable air conditioners can be very convenient and energy efficient, choosing the wrong type of portable cooler for your home or work place can leave you sweltering in the heat or worse.  Here are the top five mistakes consumers make when choosing a portable cooling unit:

1. Purchasing the Wrong Type of Cooler for a Given Environment
Consumers often mistakenly interchange the terms "portable air conditioner" and "swamp cooler." Although both types of portable coolers perform the same function - lower the temperature of the air - they utilize completely different cooling methods and are each best suited for certain types of environments.

Portable air conditioners consist of a box that holds both the hot and cold side of the air conditioner in one and they utilize an exhaust hose to expel heat. Water is condensed out of the air and collected in either an internal drain bucket or exhausted out of a drain hose. Some portable air conditioners such as the NewAir AC-1400E use advanced auto-evaporative technology which eliminates the need for emptying the water tank.

On the other hand, swamp, or evaporative coolers, are somewhat simpler and consist of a large box-like frame containing a large fan which is walled in by water-cooled pads. The fan blows the hot outside air through the continually-soaked water pads and cools it by up to 20 degrees. As the water molecules are evaporated by the pads, the fan then blows this water-cooled air throughout an area or room.

Generally speaking, because portable air conditioners also function as dehumidifiers, they are best suited for areas with moderate humidity levels, while swamp coolers work best in dry climates, such as the Southwestern states. Therefore, if the humidity level in your environment is above 20%, a swamp cooler will not work or be effective, and a portable air conditioner will more suitable.

2. Miscalculating BTU's and Room Size
It is generally accepted that the "right way" to measure an air conditioner's efficiency is to simply calculate BTU's and select a unit that will provide comfort in a wide variety of conditions, but unfortunately, this method can sometimes be incorrect. While it is true that BTU's are an important consideration to look for when purchasing an air conditioner or swamp cooler, be sure to choose your BTU's wisely.

BTU's stand for British Thermal Units and it is a way to describe a cooler's power and cooling capacity. The higher the BTU value, the stronger the air conditioner, but the size you need will greatly depend on the area being cooled. If you choose a cooler with the wrong BTU's, cooling efficiency can be jeopardized. For example, if you choose a portable air conditioner or swamp cooler with a higher BTU rating than the corresponding room size, the unit will cycle off too quickly and will not properly remove humidity from the other hand. On the other hand, if a portable cooler has a lower BTU rating than the required room size, the unit will not adequately cool your area. Therefore, when considering BTU's, always keep in mind your room's dimensions and where the unit will be located. Sunny areas will require an additional 10% in BTU's; shaded areas require a reduction of 10% in BTU's, and kitchens will need an additional 4,000 BTU's.

3. Ignoring EER Ratings
EER, or the Energy Efficient Ratio, is a measure of how efficiently a cooling system will operate when the outdoor temperature is at a specific level - usually 95°F. EER is calculated as a simple ratio of BTU's to the amount of power a unit consumes in watts. Here is an example using an air conditioner with 12,000 BTU's and consuming 1500 watts of power:

EER = BTU's / Watts

12,000 / 1500 = 8

EER = 8

While it is true that the higher the EER and BTU's, the more efficient the cooling system, many consumers make the mistake of purchasing oversized portable air conditioners and ignoring EER ratings. The following is an example of an air conditioner with 12,000 BTU's and 1200 watts:

This would mean that this second unit can produce the same amount of cooling but more energy efficiently. Therefore, to save money on your monthly electric bill, choose a cooling system by getting an appropriately sized unit with a high EER.

4. Venting
If you decide to purchase a portable air conditioner, it is important to understand that the unit will need to be vented, either through a window, wall, or drop ceiling. Because all portable air conditioners exhaust hot air from indoors to the outside and also work as humidifiers, almost all portable air conditioners need to be vented, and this usually entails draining water into a bucket or out a window. Portable air conditioners also usually include venting kits which with a hose and window kit that provide venting options for a variety of window styles and sizes. When purchasing a portable air conditioner and if venting through a window, make sure the window you intend to install the vent on matches the type of window covered by the kit, such as sliding or casement type windows. If venting is out of the question, there are a few portable air conditioners which do not require venting, such as the Amcor APC2000E.

5. Electrical Power Problems
When purchasing a portable air conditioner, make sure you have sufficient electrical power available for the unit to prevent breaking a fuse, as these units usually require a decent amount of power. Pay attention to the type of plug in your wall outlet, and keep in mind that smaller portable air conditioners such as the NewAir ACP-1000E only require 115-volt outlets, while larger 115-volt units may need a dedicated circuit. Larger portable air conditioners, on the other hand, may require a 230/280-volt circuit.

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