High water temperature: the outlet temperature is generally required to be 65°C, and it can reach about 55° in winter. High reliability: the total design life is up to 22,000 hours under the condition of high condensation temperature throughout the year. Europe requires longer life, high load in summer and high pressure ratio in winter, and the reliability requirement is higher than that of air conditioning compressor. Wide range: compressor operation requirements of high flow and high load in summer and low flow and high pressure ratio in winter; High energy efficiency: the thermal efficiency of the operation system throughout the year, especially in winter heating performance advantage is obvious.