If you want to stay comfortable in the heat of Charlotte’s long summers while avoiding outrageous electricity bills, efficient air conditioning is what you need. Installing a high-efficiency air conditioner isn’t the only way to achieve this. Taking care of your appliances and electronics, making a few home efficiency upgrades, and regularly maintaining your air conditioner all help keep you cool for less.
Don’t Heat Up the House
The air conditioner works by removing heat from your home rather than by producing cool air. The more heat in your home, the more energy the air conditioner has to expend to get rid of that heat. Producing less heat indoors is one way to lighten the load on your cooling system.
Use appliances that produce heat, such as the clothes dryer and oven, only during cooler times of the day. If you want to heat up food in the middle of the day, use the microwave. After cooking and showering, run exhaust fans for a few minutes. These fans quickly draw out built-up heat and humidity, leaving less work for your A/C.
Replace traditional incandescent light bulbs with energy-efficient alternatives. Compact fluorescent (CFL) bulbs or LED lights not only use less energy to produce just as much light, but they also burn cooler. That means they add less to your home’s cooling load and they’re safer, especially if you have children.
Hold Back the Heat
Producing less heat inside helps, but it’s not enough to achieve truly efficient air conditioning. Most of the heat that builds up in your home comes from outdoors. Improving your home’s thermal envelope, or weather barrier, goes a long way toward keeping your home cool.
Start by sealing the air leaks around your home that let in heat, humidity and air contaminants. This low-cost home improvement will give you not just more efficient air conditioning, but also more efficient heating by keeping your furnace’s warm air indoors through the winter. Locations to check for leaks include:
- Doors and windows
- Appliance and exhaust vents
- Entry points for water and gas pipes, and electrical and phone lines
- The side of any staircase that meets an exterior wall
- The attic, including the access hatch, utility line entry points and knee walls
- Between the rim joists in the basement
- Outside your home around the foundation sill plate
Inside the house, leaks around objects that don’t move, such as window frames and exhaust vents, can be sealed with all-purpose acrylic latex caulk. For exterior leaks, choose a caulk designed for outdoor use, such as butyl rubber.
Leaks around movable surfaces of doors and windows can be sealed with weatherstripping. The type you need depends on where you plan to use it.
Unsealed air ducts can leak up to 30 percent of the air they carry, reducing the amount that reaches your rooms and contributing to moisture and mold problems in the attic and basement. To enjoy more efficient air conditioning and heating, apply mastic to seal the points where two ducts meet or where ducts connect to air registers and vents. For even greater energy efficiency, ducts that run through unconditioned spaces, such as the attic, should be insulated to at least R-6 level.
Even on mildly warm days, your attic’s temperature can pass 100 degrees. To keep that heat from seeping into your rooms, you need good attic insulation. In the Charlotte area, that means an R-30 to R-60 layer, or a minimum of 10 inches of fiberglass batts. If you have less, you can lay more batts yourself or contact a heating and cooling technician about installing loose-fill insulation.
To boost your home’s efficiency even more, your technician can perform a home energy audit to find other areas that need more insulation or further improvement.
Your windows can introduce up to 30 percent of the heat that gets into your home, but there are ways to reduce that. Upgrading to Energy Star-qualified windows, installing sun screens and hanging reflective blinds or drapes with heat-reflective backings can all help.
Keep Your Air Conditioner in Top Form
Skipping air conditioner maintenance just one time can reduce your system’s efficiency by 5 percent, and it adds up every year you avoid caring for your system. This is true even for brand new, high-efficiency air conditioners. Some of the most important maintenance jobs that help ensure efficient air conditioning are those you can perform yourself.
Debris on the air filter interferes with airflow and forces the fan motor to use more energy. For more efficient air conditioning, check the filter monthly and replace it when it’s dirty. Cheap fiberglass filters rarely last longer than a month. If you want something that lasts longer and improves your indoor air quality, opt for a pleated filter with an MERV of 5 or higher.
The outdoor A/C component also needs good airflow to maintain top efficiency. Periodically use a brush to remove the lawn clippings, dead leave, and other yard waste that stick to the unit’s exterior.
Check on the indoor evaporator coil once a year, too. Dust on this coil interferes with its ability to absorb heat from the air, forcing it to use more energy. Even a millimeter of dust is enough to reduce the coil’s efficiency, so if you notice it’s dirty, clean it with foaming coil cleaner. If you’re not comfortable removing your system’s components, leave this job to a pro.
Your cooling system requires professional maintenance once a year, preferably at the start of the cooling season. Many of the maintenance jobs a professional does help increase the system’s efficiency. These include:
- Testing the motor’s performance
- Checking the refrigerant charge
- Measuring airflow across the evaporator and condenser coils
- Repairing loose wires and corroded electrical connections
- Testing the operation of the thermostat and controls
Once your A/C reaches approximately 10 years of age, it’s approaching the end of its life expectancy and it’s no longer capable of providing truly efficient air conditioning. Today’s air conditioners are between 20 to 40 percent more efficient than those made a decade ago. If you have an older system, upgrading to a new model will give you lower cooling bills and the peace of mind knowing that your A/C won’t die on you one hot summer afternoon.
Give Your A/C a Helping Hand
Using ceiling fans is one of the easiest ways to enjoy more efficient air conditioning. These fans produce a wind chill effect that can make you feel several degrees cooler. When you feel cooler, you won’t need to keep the thermostat temperature so low. Every degree you set the temperature above 78 degrees can take between 1 to 3 percent off your cooling bills.
When you’re in bed or away for the day, you can save even more energy by leaving your air conditioner off altogether. Installing a programmable thermostat makes it easy to keep up with your energy-saving temperatures. This thermostat automatically runs your system at the temperatures and times you program in. You can set the air conditioner to remain off all day, then have it kick on an hour before you get home so you save energy without sacrificing comfort.
Humid air makes you feel hotter than dry air, so excess humidity in your home can lead you to lower your A/C temperature to compensate and waste energy in the process. If you find mildew around your home, condensation on your windows all year, or you feel uncomfortably sticky and sweaty even with the A/C going, take steps to reduce your indoor humidity.
Repair any leaky faucets, insulate sweating pipes, make sure your appliances are vented to the outdoors, and avoid hanging wet laundry to dry indoors. You may also benefit from better ventilation. Putting in trickle vents above the windows can help with minor moisture problems, but for more serious ones, talk with a heating and cooling technician about installing a balanced whole-house ventilation system. To control high indoor humidity, a whole-house dehumidifier is an effective option.
For more information on efficient air conditioning, check out Ross & Witmer’s affordable cooling solutions, or call 704-392-6188.