The nozzle body is entirely concealed above the ceiling, leaving only the edge of the sleeve level with the ceiling surface. A decorative cover plate is positioned at the sleeve's opening, harmonizing in color and texture with the ceiling to ensure total visual integration. As with all wet fire protection systems, the pipes that connect the sprinkler bodies are perpetually filled with pressurized water, standing ready to respond at a moment's notice.
When a fire breaks out indoors, the heat generated by the high-temperature smoke and flames will accumulate beneath the ceiling. The fusible alloy solder between the decorative cover plate and the sleeve melts at its specific melting point temperature (typically 135°F / 57°C or 165°F / 74°C, etc.). After the solder melts, the decorative cover plate, which has lost its adhesive force, will automatically fall down under the effect of Earth's gravity, exposing the nozzle body and the splash tray hidden above the ceiling.
