How to unload the water from the fire hydrant on the floor, which valves need to be closed and where are the valves?

The drainage of the fire hydrant floor should be provided with the ring network at the bottom and top, generally 18 floor, and the length of the ring network should not exceed 50m. Specifically, the upper and lower valves of ring network risers in high and low areas should be closed according to the actual situation on site (there are four residential buildings, some of which have double risers), and then the fire hydrant should be opened from the connecting hose on the first floor or the bottom floor for drainage.