I recently stayed with my sister, in her trendy apartment, for eight days. It was a new experience for me to be in a high-rise apartment building, in the middle of the city. I live in a cottage near the beach, with no neighbors, traffic, or cold weather. My sister lives on the twentieth floor of a building that is in the heart of downtown, in the northeastern part of the country. It was very strange to ride an elevator to get to her apartment, and to see snow outside the windows. Because the building is entirely temperature controlled, her windows don’t open. The building features a state-of-the-art heating and cooling system with exposed ductwork along the ceiling. My sister is not responsible for utilities, so she keeps her apartment extremely cool in the summer, and overheated in the winter. I visited her in January, and the apartment felt like an oven. The furnace was running all of the time, and I was constantly sweating. The apartment features two separate thermostats, with one located in the kitchen and the other near the bedrooms. I assumed that this was some type of zone control, and I repeatedly turned the thermostat near my bedroom down. It never seemed to make any difference. By the end of my stay, I figured out that both thermostats controlled the entire apartment. Every time I turned one thermostat down, my sister would turn the other thermostat up. While I really enjoyed my time with my sister, I was anxious to get outside and breathe some fresh air.