Mitsubishi Heavy Industries Thermal Systems, Ltd. worked on product development for an air-source circulation type heat pump using environmentally-friendly low-GWP refrigerant that contributes to energy saving in the industrial field, and successfully launched a product that realizes the hot water temperature at outlet of 75°C at an outside air temperature as low as -20°C, while featuring a high efficiency of the rated COP of 3.3. We also actually introduced this product as a heating source of hot water for washing production equipment and confirmed its economic efficiency and environmental effects. Through the introduction of a hybrid system of this product and an existing gas-fired steam heater, in which this product covers the base heat load, it is expected that the running cost and CO2 emissions will be reduced by about 50%, leading to a substantial reduction in environmental load.