Vehicle exhaust heat recovery with multiple coolant heating modes and method of managing exhaust heat recovery

摘要

An apparatus is provided for a vehicle with an engine that includes an exhaust system through which exhaust gas is discharged from the engine. A heat exchanger is positioned at least partially within the exhaust system. Coolant flow passages are provided in thermal communication with the engine and with the heat exchanger. A bypass valve is operable in a first mode to direct the exhaust gas across the heat exchanger along a first flow path to transfer exhaust heat to the coolant flow passages, and is further operable in a second mode to direct at least a portion of the exhaust gas across the heat exchanger along a second flow path to transfer exhaust heat to the coolant flow passages in a second coolant heating mode. The second flow path is restricted relative to the first flow path. A method of managing exhaust heat recovery is also provided.