Patent ID: 8170779

Claim:
An abnormality diagnosis device for an exhaust heat recovery equipment including: an exhaust heat absorption part configured to absorb exhaust heat discharged from an engine into a heat exchange medium; a heat release part configured to release at least part of the heat absorbed by the exhaust heat absorption part from the medium to engine coolant of the engine; a circulation loop passing through the exhaust heat absorption part and the heat release part, the medium circulating around the circulation loop; and an opening and closing valve disposed in the circulation loop between the exhaust heat absorption part and the heat release part, wherein the exhaust heat recovery equipment is configured to close the valve so as to stop the circulation of the medium when temperature of engine coolant is equal to or higher than a preset temperature, the device comprising: an abnormality determination means for determining whether the valve is in an abnormal opening state in which the valve is left open based on an amount of heat transmitted from exhaust heat to engine coolant through the exhaust heat recovery equipment, when the temperature of engine coolant is equal to or higher than the preset temperature and thereby the valve is closed given that the valve is normal.