| 摘要 |
PURPOSE:To prevent an evaporator from frost or freeze by providing an air heating circuit for circulating engine cooling water through a radiator arranged in front of the evaporator and mounting a warm water controlling valve on said circuit for controlling a cooling water path. CONSTITUTION:When room temperature, i.e. temperature of air at the inlet of an evaporator 13 exceeds a predetermined value in running a cooler, a thermo- switch 20 is turned off and a warm water controlling valve 16 closed. And engine cooling water does not flow through an air heating circuit A, and room air sucked by a fan 8 jets into the room for cooling operation after cooled by the evaporator 13. Next, when the room temperature is lowered and the air temperature at the inlet of the evaporator 13 reaches frosting temperature at the ouetlet of the evaporator, the thermo-switch 20 is turned on and the warm water controlling valve 16 opened so that warm water flows through a radiator 15 after cooling the engine. Thus, the room air is heated while it passes through the radiator 15 and enters the evavorator 13 so that the air temperature at the inlet of the evaporator 13 is raised and the air temperature at the outlet exceeds the frosting temperature to prevent the evaporator from frost. |
