Clean and/or replace your air filters on a monthly basis. I recommend changing your filters on the 1st of the month. Your AC needs good, clean fresh air to operate effectively and efficiently.
Do not place heat generating appliances like televisions, computers or lamps anywhere near your thermostat. Your thermostat will get fooled in to thinking it is hotter in your room than it actually is, causing your AC to run longer and work harder than necessary.
Maintain cooling systems. It’s not enough to use an energy-efficient AC and install a programmable thermostat. If you don’t properly care for your equipment, it won’t reduce your cooling costs. Dirty AC filters block airflow and make units work harder to cool your home. Cleaning and/or replacing filters once per month will lower an AC’s energy consumption by 5% to 15%. If you have a central cooling system, be sure that floor registers aren’t blocked with dust—or furniture. A unit’s evaporator and condenser coils (located outside) should also be clear of dirt and other debris (fallen leaves, branches, grass). And clip foliage so that it always remains at least 2 feet from the condenser.