You are correct about the - 40c miscibility problems . the oil has to have a low pour point in order to flow and still have sufficient viscosity for the compressor lubrication 你談到油在40度的溶解性的問題是正確的。油不得不具有有一個很低的流動點(流(動)點:油或其他液體在規定條件下流動的最低溫度) ,還需要有足夠的粘度作為壓縮機的潤滑作用。