In the heat pump cycle, Q0 kcal/h of heat is obtained from the low-temperature heat source (outdoor air or circulating water, the temperature of which is higher than the evaporation temperature t0), consuming mechanical work ALkcal/h, and is transferred to the high-temperature heat source (indoor heating system) Q1 kcal/h of heat is supplied. The relationship between these heats is in accordance with the first law of thermodynamics, that is, Q1=Q0+AL kcal/h. If a heat pump device is not used, the heat converted by mechanical work (or electricity If the high-temperature heat source can be directly heated, the heat obtained is ALkcal/h. After using the heat pump device, the high-temperature heat source (heating system) obtains more heat: Q1-AL=Q0 kcal/h. This heat is obtained from the low-temperature heat source. , this heat cannot be obtained without a heat pump device. Therefore, a heat pump device can not only save fuel, but also utilize waste heat. The working cycle of a heat pump is exactly the opposite of that of a heat engine. A heat engine uses the energy of a high-temperature heat source to generate mechanical work. , and the heat pump transfers the heat from the low-temperature heat source to the high-temperature object by consuming mechanical work. The heat pump has two identical heat source temperatures, and the relationship between them is: φ=Q1╱AL=(Q0+AL)╱ AL=ε+1, ε is the refrigeration coefficient of the refrigerator. It can be seen that the minimum value of the heat conversion coefficient is φ=1. In this extreme case, ε=0, Q0=0, that is, no low-temperature heat source is absorbed. heat.