Friday, June 28, 2013

Whole House Air Conditioning Vs Window Units


During the summer, air conditioning becomes essential for many people, especially in the humid Deep South and the scorching deserts of the Southwest. There are two kinds of air conditioners: wall/window units and whole house units, or central A/C systems. Both types of A/C cool and dehumidify, but differ in energy use and scale of their cooling properties. Here is some information about each type.

How Air Conditioning Works

Air conditioning is complicated. A/C units have complex systems of compressors, heat pumps, fans, fan motors, and coolant circulation. Hot, moist air is taken in from the outside and put through a series of processes that cool it and remove the majority of the moisture. It is then forced through an outlet vent into the inside of the home, lowering the ambient temperature. In the past, carcinogenic and environmentally destructive CFC's were used as the coolant gas. Now, other substances are used. All air conditioning units will require coolant, external ventilation, and an electrical power source.

About Window Units

Window units, wall units, or split A/C units are all variations on the same thing, which is a single-room A/C system. They can be permanently installed in the room through a hole in the wall or placed in a window. The ventilation and cooling system are contained within the body structure of the unit, which can be plugged into an outlet or hard-wired. The electrical installation will depend on how many BTUs the unit needs to operate efficiently, but most units consume about 900 watts per kWh. Prior to buying window units, measure the space to be cooled so you can buy an A/C that will cool it without overworking.

Pros and Cons of Window Units

Window units are portable to a large degree, although moving them around often can be detrimental to its internal components. The unit's size is very important. If it is too small, it will run constantly, driving up your energy bill. A large unit will cool inefficiently and cause clammy humidity buildup in the room. Wall units are also prone to dripping and leaks, especially in very humid climates. They can be noisier than central A/C. Window units can be less expensive than central A/C if they are only used in small areas and the thermostat is set to a moderate temperature. They also are inexpensive, as little as $300.

About Whole House Air Conditioning

Whole house A/C is also known as central air. This is a larger air conditioning unit, consisting of a condenser (normally placed outside the house) a blower fan, and a cooling coil system. The warm air from outside is condensed, channeled into the fan and cooled by the coils, and forced through the home's existing ductwork into the rooms, thus cooling and dehumidifying the air. If the home does not have a forced-air furnace, the fans and the cooling coils will be placed in the attic. The thermostat will regulate the home's temperature level. Whole house 2.5-ton A/C units consume about 3500 watts of electricity per kWh.

Pros and Cons of Whole House A/C

If you have a house with several rooms that need to be cooled, installing a whole house unit is the way to go. The installation cost of a central A/C unit will vary on the region, type of unit, and the amount of customization that needs to be done to the home. If the home does not have existing ductwork, the installation will be much more expensive, since that will have to be added. Whole house units dehumidify and condition the air, removing allergens and irritants, making the environment better for everyone. Make sure enough cold-air returns are installed, and only choose a unit with a high seasonal energy efficiency rating.

Maximizing Efficiency in Both Types

There are many ways to make the most of each kind of A/C unit's cooling power, while keeping your electric bill reasonable. Set the temperature at 78F, because every degree below this mark increases energy consumption by as much as 4%. When you leave, increase the temperature to 80F or more. Set the blower fan at a lower temperature to help circulate the air better. Insulate your home well, especially on the sunward-facing side, which will keep the home at an even temperature yearlong. Replace filters, clean ducts and/or intakes/outlets frequently to prevent clogs, and check that the coolant level is sufficient.

When deciding whether to install window units, whole house A/C, or a combination of both, consider the number of rooms you need to cool and your installation budget. Regardless of which type of air conditioning you choose, set the thermostat at a reasonable temperature and maintain them well to ensure maximum cooling efficiency.

No comments:

Post a Comment