A falling film evaporator includes a heat transfer tube group with heat transfer tubes extending longitudinally, a tank having a refrigerant flow inlet, a liquid refrigerant distribution part, a vapor outlet pipe extending out from a lateral or upper position of the tank other than a top of the tank as viewed along a longitudinal direction of the tank, and an isolation member covering a place below a lowest portion of a connection portion of the tank and the vapor outlet pipe as viewed along an axial direction of the heat transfer tubes. Liquid refrigerant supplied through the refrigerant flow inlet falls downwardly onto the heat transfer tube group. The isolation member extends between the vapor outlet pipe and the liquid refrigerant distribution part to allow refrigerant to pass through an upper portion. A longitudinal direction of the isolation member is the same as the heat transfer tubes.

Claims data not available