A valve device comprising: a case comprising an open lower portion and an accommodation space formed therein; a base plate to cover the open lower portion of the case ; an inlet pipe connected to the base plate and formed to introduce a refrigerant to the accommodation space therethrough; a boss installed to the base plate and comprising a plurality of refrigerant inlet and outlet holes through which the introduced refrigerant from the accommodation space is introduced and discharged; a plurality of inlet and outlet pipes respectively connected to the plurality of refrigerant inlet and outlet holes , and through which the refrigerant is introduced from the boss or discharged to the boss ; and a pad comprising an open cavity formed therein to selectively open one refrigerant inlet and outlet hole among the plurality of refrigerant inlet and outlet holes , and a connection cavity formed therein to selectively connect two refrigerant inlet and outlet holes among the plurality of refrigerant inlet and outlet holes , wherein the open cavity comprises a first region formed on one side of the open cavity and a second region formed on an other side of the open cavity and provided at a position rotated 45 degrees clockwise from the first region with respect to a center of the pad ; the first region is a portion adjacent to a left end and the second region is a portion adjacent to a right end when the pad is viewed from the top; and wherein the open cavity has a size that allows the first region or the second region to selectively open one refrigerant inlet and outlet hole among the plurality of refrigerant inlet and outlet holes . a case comprising an open lower portion and an accommodation space formed therein; a base plate to cover the open lower portion of the case ; an inlet pipe connected to the base plate and formed to introduce a refrigerant to the accommodation space therethrough; a boss installed to the base plate and comprising a plurality of refrigerant inlet and outlet holes through which the introduced refrigerant from the accommodation space is introduced and discharged; a plurality of inlet and outlet pipes respectively connected to the plurality of refrigerant inlet and outlet holes , and through which the refrigerant is introduced from the boss or discharged to the boss ; and a pad comprising an open cavity formed therein to selectively open one refrigerant inlet and outlet hole among the plurality of refrigerant inlet and outlet holes , and a connection cavity formed therein to selectively connect two refrigerant inlet and outlet holes among the plurality of refrigerant inlet and outlet holes , wherein the open cavity comprises a first region formed on one side of the open cavity and a second region formed on an other side of the open cavity and provided at a position rotated 45 degrees clockwise from the first region with respect to a center of the pad ; the first region is a portion adjacent to a left end and the second region is a portion adjacent to a right end when the pad is viewed from the top; and wherein the open cavity has a size that allows the first region or the second region to selectively open one refrigerant inlet and outlet hole among the plurality of refrigerant inlet and outlet holes . <EOS>