Winter survival supplies - fresh batteries

The Phactors were just sitting around the other evening reading the Sunday papers and assorted other periodicals, and eventually it came to their attention that they were cold. Say what?  Yes, the temperature in the house was several degrees below what is considered comfortable. Sort of reminded TPP of the story about putting a frog in a pot of water and warming it so slowly such that the frog never jumps out and just gets cooked. Might the same thing happen to a couple of senior citizens that are found sitting there with their papers frozen? How come they didn't see why the furnace wasn't coming on?  Naturally this event kicks problem solving activities into high gear, and the first suspect was the battery-powered thermostat, which itself did not seem to be responding. The decision was made to change the 2 AA batteries only to discover that a self-destructing battery was threatening the integrity of the whole thermostat, and leaving you wondering how it could have been working at all?  So, keep some fresh batteries on hand because this is one of those things, one of those times, when fancy programmable thermostats reveal their weakness, they need some juice!