As summer temperatures begin to rise, homeowners depend on a reliable central air conditioning system to keep the indoor environment cool, quiet and healthy. During regular operation, motors and other internal moving parts are subject to constant wear and heat stress. Over time, equipment performance will begin to decline while repair costs start to escalate. Obsolete AC units often fail in extreme weather, which can compromise the health and safety of young children and the elderly. Homeowners with equipment that is more than eight years old will appreciate the many benefits of a new energy efficient central air conditioning system.
Improved EfficiencyThe Seasonal Energy Efficiency Ratio (SEER) rating is a standard adopted by the Department of Energy to provide consumers with a method to compare the operating costs of different brands and models of air conditioners. Replacing a 10 SEER unit installed in the early 2000s with a modern 16 SEER AC system can save up to 40 percent on monthly cooling costs. When combined with a fuel efficient furnace, the annual savings can be even higher.
The Benefits of Proper SizingPerformance metrics for air conditioning systems were largely unavailable until the implementation of sophisticated building science protocols in the early and mid 2000s. The lack of quantifiable data left HVAC contractors with inadequate tools for proper equipment sizing. In many instances, AC units were purposely oversized to avoid the more serious problem of inadequate capacity. Unfortunately, oversized equipment will short cycle, which negatively impacts comfort and degrades humidity control. Indoor temperatures can fluctuate rapidly, and the occupants often feel uncomfortable, warm and sticky. ACCA Manual J load calculations are designed to include the building’s unique energy consumption characteristics when determining total capacity requirements. This includes the effect that insulation levels, windows, doors, perimeter tightness, duct leakage and local climate conditions have on the total load. Equipment is selected to match the precise cooling requirements of the building in the most severe conditions. In many instances, equipment tonnage can be downsized while dramatically improving efficiency and indoor comfort.
Better Indoor Air QualityEvery new AC installation will include a comprehensive analysis of the air distribution network. Until recently, duct systems were not subject to clearly defined installation standards. Connections that are loose or improperly sealed can result in a substantial loss of performance. Negative pressure leaks can draw contaminants into the living area from the attic or crawl space, which may cause serious indoor air quality issues for those with allergies and other respiratory ailments. When a new air conditioning system is installed, the ductwork will be inspected and modified to ensure that the performance at the air handler and register are consistent.
Advanced FeaturesAC equipment manufacturers offer a variety of advanced features designed to improve indoor comfort and enhance system efficiency. The most common upgrades include:
- Two-Stage Compressor: An AC unit equipped with a two-stage compressor has the ability to operate at two separate speeds. When the outdoor temperature is less severe, the compressor can meet the indoor load requirement while running on the low speed, which helps save energy. Since the unit accumulates a lower number of cooling cycles over its lifetime, critical components experience less wear and fatigue, which can help lower repair costs and extend the service life of the equipment.
- Variable Speed Blower: Instead of running at full speed whenever the thermostat calls for cooling, a variable speed blower is programmed to operate at the exact velocity required to meet the existing load. This provides exceptional efficiency in all weather conditions. Since the unit is designed to run continuously, the air is filtered more often, which results in better indoor air quality. Hot and cold spots are virtually eliminated by the continual mixing of the air, and the dehumidification process is much more effective.
- Noise Reduction Package: A substantial amount of research has been dedicated to reducing operational system noise. Newer units are outfitted with shock absorbing motor mounts, compressor sound blankets, forward swept fan blades and specially engineered baffles. Through proper equipment and duct sizing, air flow through the register is quiet and unobtrusive.