It is free and you will only need to download it once. It will help lower your cooling costs, while at the same time allowing you to return to a cool home. Start precooling your home by 8 a.m., setting the air conditioning thermostat to 78 degrees or below. By 1 p.m., raise your thermostat to 80 degrees or higher. Changing air conditioner filters monthly will help you save too.
Clean filters allow for adequate air flow and proper cooling.
You should have your air conditioner serviced every year. Avoid closing air vents in unused rooms. Instead, adjust vents to reduce the amount of cool air delivered. Closing off vents and rooms creates a pressure imbalance and reduces the effectiveness of your cooling system. If your home has an air conditioner as well as an evaporative cooler, don't operate both at the same time.