The Peterborough Fire Department said a fire at a nursing home Saturday is a good example of the value of having a working sprinkler system in every building. Firefighters said they were called to Pheasant Wood Center just before 1 p.m. because the fire alarm was sounding. Officials said water was runnning out from unde the door to the maintenance room on the firsit floor and smoke could be smelled on the first and second floors. Officials said a single sprinkler head had activated and extinguished the fire. The fire was caused when an electric fan caught fire and ignited other nearby combustibles.