Central AC System GuideCooling is one of the largest lines on a summer energy bill, and much of it responds to habits rather than hardware. A few verified adjustments to setpoint, airflow, and the ductwork recover real money from the same equipment. These tips come from the Department of Energy and ENERGY STAR rather than rules of thumb.
Cooling is a big share of the bill
It helps to know the stakes. ENERGY STAR reports that nearly half of a typical home's roughly 1,900 dollar annual energy bill goes to heating and cooling.
Because the category is so large, small percentage savings translate into meaningful dollars, which is why setpoint and airflow tips are worth the small effort they take.
Raise the thermostat and add a fan
The setpoint is the biggest lever. The Department of Energy reports that running the air conditioning at 78 degrees Fahrenheit instead of 72 degrees can save between 6 and 18 percent on the cooling bill.
A ceiling fan makes the higher setpoint comfortable. The Department of Energy reports that a ceiling fan lets a homeowner raise the thermostat setting about 4 degrees Fahrenheit with no reduction in comfort, so the two tips stack.
Program the schedule and keep filters clean
Automation captures savings a busy household forgets. The Department of Energy reports that programmable thermostats can save up to 150 dollars a year in energy costs when used properly.
Airflow is the other free win. The Department of Energy reports that routinely replacing the air filter can lower an air conditioner's energy consumption by 5 to 15 percent, so a clean filter pays for itself many times over.
Seal the ducts that waste cooled air
Leaky ducts undo good habits. ENERGY STAR reports that about 20 to 30 percent of the air moving through a typical duct system is lost due to leaks, holes, and poorly connected ducts.
Sealing those runs keeps the cooled air in the living space, so the system delivers what the household already pays for instead of losing it to the attic and crawl space.
Consider newer equipment when the time comes
Age eventually caps what habits can do. ENERGY STAR suggests considering replacement when heating and cooling equipment is more than 10 years old and showing signs of trouble.
The upgrade pays back over time. ENERGY STAR reports that replacing older equipment with ENERGY STAR certified systems can save a household on the order of 140 dollars a year, on top of the day-to-day savings from good habits.