A waste heat recovery system, comprising: a first heating line in a working fluid circuit including a first heat exchanger operatively connected to transfer heat energy to a working fluid; a second heating line in the working fluid circuit including a second heat exchanger operatively connected to transfer heat to the working fluid; characterized in that the waste heat recovery system further comprises: a valve section in the working fluid circuit operatively connected to the first heating line and second heating line and selectively controllable to provide a first configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in parallel and a second configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in series; at least one temperature sensor operatively connected to monitor the temperature of at least one of the working fluid and the exhaust gas flow and generate an output signal representative of the temperature of at least one of the working fluid and the exhaust gas flow; and one or more electronics operatively connected to receive the output signal from the at least one temperature sensor and responsive thereto control the configuration of the valve section. a first heating line in a working fluid circuit including a first heat exchanger operatively connected to transfer heat energy to a working fluid; a second heating line in the working fluid circuit including a second heat exchanger operatively connected to transfer heat to the working fluid; characterized in that the waste heat recovery system further comprises: a valve section in the working fluid circuit operatively connected to the first heating line and second heating line and selectively controllable to provide a first configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in parallel and a second configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in series; at least one temperature sensor operatively connected to monitor the temperature of at least one of the working fluid and the exhaust gas flow and generate an output signal representative of the temperature of at least one of the working fluid and the exhaust gas flow; and one or more electronics operatively connected to receive the output signal from the at least one temperature sensor and responsive thereto control the configuration of the valve section. a valve section in the working fluid circuit operatively connected to the first heating line and second heating line and selectively controllable to provide a first configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in parallel and a second configuration in which the first heat exchanger and second heat exchanger are operatively connected to the working fluid circuit in series; at least one temperature sensor operatively connected to monitor the temperature of at least one of the working fluid and the exhaust gas flow and generate an output signal representative of the temperature of at least one of the working fluid and the exhaust gas flow; and one or more electronics operatively connected to receive the output signal from the at least one temperature sensor and responsive thereto control the configuration of the valve section.