Steady state and dynamic instability experiments were performed at low mass velocities in a Refrigerant-113 boiling flow rig featuring a vertical electrically heated 16 rod-bundle channel. The important nondimensional parameters associated with a typical 64-rod boiling water nuclear reactor fuel assembly were matched with the exception of the Froude number. Measurements at steady states include the transverse distributions of vapor fraction and fluid temperature at two axial locations along the rod-bundle channel. The evolution of dynamic instability in the channel was studied by examining the energy spectrum of the inlet flow rate variation. The instabilities were found to be of the quasiperiodic oscillation kind. A limited parametric study of the highest energy oscillation state was carried out.