Methods and systems to manage refrigerant levels in a chiller system are provided. An evaporator of the chiller system may be configured to have a spill over port allowing oil containing refrigerant to spill over through the spill over port. The spill over port may be positioned at a place that corresponds to a desired refrigerant level in the evaporator. The spill over refrigerant may be directed into a heat exchanger that is configured to substantially vaporize refrigerant of the spill over refrigerant to a slightly superheat temperature. A method of maintaining a proper refrigerant level in the evaporator may include regulating a refrigerant flow to the evaporator so that the vaporized refrigerant of the spill over refrigerant is maintained at the slightly superheat temperature.