What should the HVAC settings be?

I was talking to my one son, who is a truck driver.  He was going through a blizzard in the middle of Arizona.  He said he had inches of snow on his truck, and he had driven quite the distance. He had his television on, and he was drinking a cup of fresh coffee. He was bragging that he had the best HVAC system in a truck possible, and it was all in the front of his cab.  I had to laugh, because he lives in the South, where all the people panic if it gets below sixty. He told me that he had to buy a space heater to keep his feet warm. Now he is too warm, and his feet are covered in sweat. The baby just can’t get comfortable. He is laying in his truck, in shorts and flip flops, and bragging about his HVAC.  He called me a couple of minutes later, when he got to CA. He said that the temperature was up to sixty, and he was ready to turn off the heater. Tomorrow, he is to be somewhere else, where the average temperature is supposed to be about eighty. Just like that, it’s the a/c he’ll have need of. I’m not sure if I could handle such extreme temperature changes where you need heaters one day, and by the next morning, you have the cooling system blasting.  I could never be a truck driver or anything that would take you through so many weather conditions in such a short time. Next month he will be back home, and I’m sure he’ll be happily swimming in his pool, and he’ll have forgotten all about the snowstorm and heater..

HVAC program