Wet pipe sprinkler system, water-filling method, and method of dealing with a water leak thereof

PURPOSE: A wet piping system, method for water filling and approaching method to problem are provided to take a proper action immediately when a water leakage happens at a head of a sprinkler. CONSTITUTION: The wet piping system comprises a pipe arrangement(p) supplying water for extinguishing fires which is provided at a head(180) of a sprinkler; a water-supply system connected with an end of the pipe arrangement; an electric main valve(110) controlling inflow of the water for extinguishing fires into the pipe arrangement from the water-supply system; an electric drain valve(190) discharging the water provided at the other end of the pipe arrangement for extinguishing fires within the pipe arrangement and; an electric wiring(310) arranged to block flowing of the water for extinguishing fires into the pipe arrangement. The electric wiring outputs close signal to the main vale for blocking the main valve and open signal to the drain valve for opening of the drain valve when a water leakage happens at the head of a sprinkler.