HEAT SOURCE UNIT AND FREEZER

• Main Authors: KONDO AZUMA, SAKAE SATORU
• Format: Patent
• Language: English; Japanese
• Published: 01.03.2021
• Subjects: BLASTING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; HEATING; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; REFRIGERATION MACHINES, PLANTS OR SYSTEMS; REFRIGERATION OR COOLING; WEAPONS

To improve accuracy for determination that the opening of a utilization side expansion valve has increased, in a first operation of reducing the opening of a heat source expansion valve in an oil recovery operation.SOLUTION: An oil recovery operation includes a first operation of reducing the opening of a heat source expansion valve (28) and a second operation of increasing the opening of the heat source expansion valve (28) after the first operation. A controller (80) is configured to execute the second operation when the first condition is satisfied during the first operation. The first condition includes at least a condition that the difference ΔP between the pressure of refrigerant on the downstream side of the heat source expansion valve (28) in a liquid pipe (43) and the pressure of suction refrigerant of a compression element (C) is smaller than a predetermined value.SELECTED DRAWING: Figure 4 【課題】油回収運転において、熱源膨張弁の開度を小さくする第１動作において、利用膨張弁の開度が大きくなったことの判定の精度を向上する。【解決手段】油回収運転は、熱源膨張弁（28）の開度を小さくする第１動作と、該第１動作の後、該熱源膨張弁（28）の開度を大きくする第２動作とを含む。制御器（80）は、第１動作中に第１条件が成立すると第２動作を実行するように構成される。第１条件は、液管（43）における熱源膨張弁（28）の下流側の冷媒の圧力と、圧縮要素（C）の吸入冷媒の圧力との差ΔＰが所定値より小さい条件を少なくとも含んでいる。【選択図】図４