Another thing to remember is the humidity levels. During this period, dendrobiums do not need a lot of moisture. Very little water will be enough to keep their roots alive. Also keep in mind that their roots constantly need plenty of air circulation so you should place them where there is a lot of fresh air.
Remember, that is based on energy usage, not comfort-levels, which are the purpose of having an air conditioner, in my not-so-humble opinion. Fact: At night, the ideal temperature comfort range for Americans drops to 65 to 72 degrees Fahrenheit (or about 87 degrees if you are my wife).
For a house the temperature should be at 70 degrees. this is the most effective temp for the day time, and at night you want the temp to be at about 65-67 degrees. Studies have shown that these are the best temperatures to have a home be at. These temps will save you money all year round. And are vey comfortable. Mold is less likely to grow.