I am an energy consultant working with homeowners of existing homes. Could use a little input on a recent question. Customer has a second home, upstate NY, ZONE 5, and resides only weekends. Asks what should I set back my t-stadt to during the 5 days a week we are not here? 1998 home, oil boiler, 3 zones, indirect hot water heater. Typical conventional (ranch) construction. I have come to believe too much setback short-term can be both an energy and comfort penealty in an average to poor enclosure home. When you get into multiple days setback I'm thinking common sense is the more the better and vacation mode on the dhw. Anybody have any insights would be greatly appreciated.