Central air conditioners work by circulating cooler air through a series of ductworks. This cooler air is then carried back into the home through supply ducts and registers built into the walls, floors, or ceilings of the dwelling. Inside your home, it becomes warmer and is then sucked back into the ducts through the series of ducts and registers to be once again cooled and redistributed. If this system fails to work properly, you may be able to find some helpful tips in a AC repair articles around the web, but most will require professional assistance.
Another service performed by your air conditioner is that it dehumidifies the air, further improving your comfort level. When outdoor temperatures and humidity are high or when your air conditioner is too big for the space it is cooling, you might not achieve the ideal level of humidity in your home. This can be adjusted by reducing the thermostat setting or investing in a dehumidifier. However, either method will reduce energy efficiency because the air conditioner requires more energy to cool your home and the dehumidifier itself uses additional energy.
If you have trouble with your AC unit properly distributing cool air, you can set the fan to “auto” and instead use exterior fans to cool separate areas of your home. This basically keeps your central unit from using its interior fan to provide air circulation and allows you to direct it using alternate means. However, this isn’t an ideal solution. Instead, you should begin looking for an air conditioning system that doesn’t require you to use workarounds to accomplish its goal of keeping your home at a comfortable temperature.
Let’s look at some of your options.
Types of AC Systems
Central air conditioners can be a single packaged unit. They might also be a split system.
Split system central AC houses the exterior heat exchanger, fan, and compressor in an outdoor cabinet. The interior heat exchanger and blower are housed in a cabinet located on the interior of your home. In some cases, the indoor cabinet may also house the furnace. It might also house the interior heat exchanger of a heat pump. If your home has a separate furnace, a split system can be the most inexpensive option for installing central air conditioning in your home.
In a single-package central air conditioner, both heat exchangers, the compressor, the fan, and the blower are all contained within a single cabinet. It is usually located on top of a flat roof or a concrete pad near the foundation of your home. The ductwork exits and enters the home’s exterior roof or walls to connect with the air conditioner package. This type of system usually includes a gas furnace or perhaps electric coils for heating. This combination of heating and cooling systems removes the need for separate heating measures.
A correctly installed HVAC system should perform at optimum efficiency for years to come with only routine maintenance and minor repairs. If you have an older system, one that hasn’t been maintained properly, or one that has experienced damage, this may not be the case, leaving you facing the costs of replacing your existing system. In a case of poor installation, even the most modern of HVAC systems can perform as poorly as an older model nearing the end of its lifespan.
However, when installed correctly, newer air conditioning models can greatly outperform their older counterparts. Here are some things you should make sure your installer does when installing an improved HVAC system for you:
- Allows enough room indoors for installation, maintenance, and repairs
- Installs correct duct sizing according to Air Conditioning Contractors of America guidelines
- Installs enough supply registers to adequately circulate air
- Seals and insulates ducts
- Locates the condensing unit where it creates the least nuisance during sleep hours
- Locates the condensing unit so that there are no blockages of airflow
- Verifies that the installation is completed per the manufacturer’s specifications
- Places the thermostat so that no heat sources interfere with the correct operation
Choosing an HVAC Upgrade
Central AC systems are far more energy efficient than window or portable air conditioners. They are also quieter and more convenient. Your choice should be an educated one, taking into consideration the size and layout of your home, added features, and energy efficiency ratings.
The most efficient air conditioners on the market today use 30% to 50% less energy than those air conditioners available before the turn of the century. An HVAC system that is only ten years old may use as much as 20% to 40% more energy than a newer, more efficient model.
However, as stated before, your HVAC system is only going to be as good as its installation. Likewise, a system that is too large for the space it is intended to cool can work against itself by not adequately removing humidity. An HVAC system that is too small will be unable to pull its weight on the hottest days. A poor choice of locations, poor insulation, and improperly installed ductwork can also diminish efficiency. When asking whether your newer air conditioner will be more energy efficient, you must make sure you aren’t preventing it from achieving its highest efficiency by not providing the best circumstances for it to do so.
That being said, in selecting an upgrade for your existing HVAC system or a system for a new home, you should look for the model with the highest efficiency ratings. Central air conditioners are given a seasonal energy efficiency ratio (SEER) or rating. SEER relates to the relative amount of energy required to provide cooling output points. Many newer air conditioning systems have SEER ratings far superior to older models, some as high as 26.
When buying a newer model, look for the Energy Star or Energy Guide labels or ask your HVAC contractor to provide the ratings of suggested systems as a part of your estimate from them. Units qualified by either of these standards are as much as 15% more efficient than other models. The higher the SEER rating, the more energy efficient the system will be. Keep in mind too that while your existing unit is not required to meet SEER ratings required by local standards, the purchase of a new unit will require you to adhere to such guidelines.