Reducing the Cost of Central Air Conditioning
The best way to reduce air conditioning costs is to keep your home from heating up in the first place.
Start by using low-cost cooling measures like window shading. Close your shades in the morning to limit window solar gain during the day. Exterior fabric sunscreens can also slow solar gain, and are inexpensive and easy to install.
Close your windows and doors in the morning. Open them on cool nights to cool the home.
If everyone leaves during the day, turn the air conditioner thermostat up to save energy, or install a programmable thermostat that will adjust the temperature while your gone.
Air conditioner efficiency is also dependent upon routine maintenance. The difference between the energy consumption of a well-maintained air-conditioning system and a severely neglected system ranges from 10 to 40 percent.
Clean or replace indoor filters every 1 to 4 months. These are located in either the furnace/air handler cabinet, or at a central return air grille.
Clean the fan blades of the indoor blower. If the blower is dirty, then the indoor evaporator coil is probably dirty too. You can see the blower by removing a panel on your furnace or air handler cabinet.
Clean the indoor evaporator coil and condensate pan every 2 to 4 years. Straighten any bent fins to improve airflow.
Clean room supply and return registers. Straighten their fins.
Remove plant matter and debris from around outdoor condenser as well as from around the coils. This should be done every few years. Straighten any bent fins.
You'll also improve the efficiency of your central air conditioner by maintaining the proper refrigerant charge. This is a job for professionals.