Central air conditioners are one of the most energy intensive appliances in the home. Using a programmable thermostat to automatically control the cooling schedule can avoid energy waste, increase comfort and save you money. So what about when you're going to be away from home on vacation for more than a few days? Should you turn the AC completely off, or just turn the temperature up so it runs less often?
One important factor to consider is humidity. If the forecast includes a chance that the temperature and humidity are going to reach tropical levels, mold and mildew could be a concern if the windows are closed. Remember, an air conditioner doesn't just cool the air, it removes moisture. Turning the thermostat up 10 degrees will enable the AC to turn on every occasionally and keep humidity levels in check.
Have a smart thermostat? Some include an app that will let you monitor temperature and humidity while you're away. If the temperature and humidity get too high, you can simply turn on the AC when your away.
If excess humidity is not a concern and you plan to turn off the air conditioner while you're away, it's a good idea to close the drapes or blinds on all windows that receive direct sunlight during the day.