Central air conditioning and heating systems are a popular choice for many homeowners. They provide a comfortable temperature throughout the home, while also helping to maintain indoor air quality. But what exactly is a central AC and heat system? Simply put, a central HVAC system heats or cools your home by feeding hot or cold air through the ductwork. While the process may seem straightforward, it requires a lot of moving parts and components to get your home to the perfect temperature.
Most often, forced air belongs to the heating system, while central air refers to the cooling system. However, people often use the two terms interchangeably. In the central heating system, heat is produced in a central location and then distributed throughout the house. On the other hand, a forced air system refers to any HVAC system that uses air ducts and vents to circulate temperature-controlled air to your home or building. Air conditioners dehumidify the air to improve comfort.
However, in extremely humid climates, when outdoor temperatures are moderate, or when the air conditioner is too large, the air may not reach a humidity low enough to reach a comfortable level. In those cases, homeowners can lower the thermostat settings or use a dehumidifier. But in both cases, this will increase energy use, both for the dehumidifier itself and because the air conditioner will require more energy to cool the house. If you have a central air system in your home, set the fan to automatic mode. In other words, don't use the system's central fan to provide air circulation; use circulating fans in individual rooms. A central air conditioner is either a split system unit or a packaged unit.
In a split-system central air conditioner, an outdoor cabinet contains the outdoor heat exchanger, fan and compressor, while an indoor cabinet contains the indoor heat exchanger and fan. In many split-system air conditioners, the indoor cabinet can contain an oven or the indoor heat exchanger of a heat pump. If your home already has an oven but doesn't have air conditioning, a split system may be the most economical central air conditioner to install. In a packaged central air conditioner, all of the heat exchangers, compressor, fan and fan are located in one cabinet which is usually placed on a roof or concrete slab next to the foundation of the house. This type of air conditioner is also used in small commercial buildings.
The supply and return ducts come from inside through an outer wall or roof of the house to connect to the packaged air conditioner. Packaged air conditioners often include electric heating coils or a natural gas furnace. This combination of air conditioning and central heater eliminates the need for a separate oven. If your air conditioner is installed correctly or if major installation problems are found and fixed, it should operate efficiently for years with only minor routine maintenance. However, many air conditioners are not properly installed.
As an unfortunate result, modern energy-efficient models can perform almost as poorly as older inefficient models. Central air conditioners are more efficient than room air conditioners. In addition, they are discreet, quiet and comfortable to operate. To save energy and money you should try to purchase an energy efficient model and reduce its energy use. In an average-sized home, air conditioning consumes more than 2,000 kilowatt-hours of electricity per year causing power plants to emit about 3,500 pounds of carbon dioxide and 31 pounds of sulfur dioxide. If you're considering adding central AC to your home, one deciding factor may be whether you need a duct network or not.
The most efficient models use 30-50% less energy than those manufactured in mid-1970s. Even if your unit is only 10 years old you can save 20-40% of cooling energy costs by replacing it with a newer model. Proper sizing and installation are key elements in determining efficiency. A unit that is too large will not properly remove moisture while one that is too small won't be able to reach comfortable temperatures on hot days. Incorrect unit location, lack of insulation and improper duct installation can greatly decrease efficiency. The regulations don't require you to change existing central AC units and replacement parts and services should continue to be available for your home systems.
The lifespan of a central AC is about 15-20 years with manufacturers often continuing support for existing equipment by making spare parts available and fulfilling maintenance contracts once new standards take effect. Both heat pumps and central AC systems use filters to remove contaminants from the air helping maintain indoor air quality.
