Valve Manifold Durgo VR2, a combined stop-, check- and vacuum valve with connection points for safety valve and drain valve. Manifolds are mainly installed in central heating plants and water heaters where they protect the installation from deformation caused by negative and overpressure, and help to prevent backflow. Manifolds can be used for filling of water heating units and plants, and shall be installed on the cold waterconduit upstream of the unit/plant. Pipe connections with compression coupling.