Abstract: A fire protection system employs a plurality of radio frequency transmitter temperature sensors remotely located around a building to be protected, one or more sprinkler heads coupled to a water supply line and mounted on the roof of the building to provide sprinkler coverage of the building and a perimeter area surrounding the building, and control circuitry responsive to a radio frequency signal transmited by one or more of the remotely located temperature sensors when a temperature exceeding a threshold temperature of the sensors is sensed thereby to initiate the flow of water to the one or more sprinkler heads for a predetermined period of time.