High velocity water spray systems are installed to extinguish fires involving liquids with flash points 65C (150F) or higher. High velocity water spray system is to protect Transformers.The system comprises of network of underground and above ground piping, control valve (Deluge Valve), sprinkler bulb detectors, water spray nozzles/Projectors.System is pressurized with water up to below the control valve ( deluge valve ) using pumps and connected to a reliable source of water supply. The piping network above the control valve remains empty consisting open spray nozzles/projectors.