Box 40-2 Fire Alarm

10-09-17. At 1438 box 40-2 was struck for a smoke detector sounding. Engine 40 responded with a crew of 2. Engine arrived and took side A. Crew had a smoke detector sounding from the 2nd floor. The house was vacant. There was no signs of smoke or fire. Crew had PD respond to the scene. Crew was able to locate a family member to let fire in to check out the house which nothing was found. Crews replaced a faulty smoke detector on the 2nd floor. Time out was 37 mins