During the summer months I would recommend you set your thermostat back during the day when you are not home. However, I would not recommend that you go over your desired temperature more than five to seven degrees. An exception to this rule is if you live in a singlewide mobile home. The insulation is so poor that you would save more by turning off the unit when you are away. Another recommendation would be that you have a programmable thermostat installed that would automatically change the setting for you. Our customers have saved as much as 30 percent on their utility bills just by setting the temperature back when no one is home.