A piping communication system, comprising: an outdoor unit case having a piping hole, wherein an outdoor heat exchanger is installed in the outdoor unit case; an indoor unit case having a piping hole, wherein an indoor heat exchanger is installed in the indoor unit case; a refrigerant piping configured to connect the outdoor heat exchanger and the indoor heat exchanger through the piping hole of the outdoor unit case and the piping hole of the indoor unit case; and a signal transmission unit electrically connected to the refrigerant piping to transfer a signal transmitted or received through the refrigerant piping to a microcomputer, characterized in that the piping communication system further comprises a short-circuit preventing member installed between the outdoor unit case or the indoor unit case and the refrigerant piping to support the refrigerant piping with respect to the outdoor unit case or the indoor unit case; and the short-circuit preventing member comprises: a support unit allowing the refrigerant piping to be inserted therethrough and supported; and a fixed unit formed to extend from an outer circumferential surface of the support unit and fixed to the outdoor unit case or the indoor unit case, wherein at least one side of the support unit is protruded than one side of the fixed unit and inserted into the piping hole provided in the outdoor unit case or the indoor unit case; and wherein the fixed unit comprises a through hole and is configured to be screw-fastened to a fastening hole of the outdoor unit case or the indoor unit case, or wherein the fixed unit comprises a hook projection and is configured to be hook-coupled to a hook hole of the outdoor unit case or the indoor unit case. an outdoor unit case having a piping hole, wherein an outdoor heat exchanger is installed in the outdoor unit case; an indoor unit case having a piping hole, wherein an indoor heat exchanger is installed in the indoor unit case; a refrigerant piping configured to connect the outdoor heat exchanger and the indoor heat exchanger through the piping hole of the outdoor unit case and the piping hole of the indoor unit case; and a signal transmission unit electrically connected to the refrigerant piping to transfer a signal transmitted or received through the refrigerant piping to a microcomputer, characterized in that the piping communication system further comprises a short-circuit preventing member installed between the outdoor unit case or the indoor unit case and the refrigerant piping to support the refrigerant piping with respect to the outdoor unit case or the indoor unit case; and the short-circuit preventing member comprises: a support unit allowing the refrigerant piping to be inserted therethrough and supported; and a fixed unit formed to extend from an outer circumferential surface of the support unit and fixed to the outdoor unit case or the indoor unit case, a support unit allowing the refrigerant piping to be inserted therethrough and supported; and a fixed unit formed to extend from an outer circumferential surface of the support unit and fixed to the outdoor unit case or the indoor unit case, wherein at least one side of the support unit is protruded than one side of the fixed unit and inserted into the piping hole provided in the outdoor unit case or the indoor unit case; and wherein the fixed unit comprises a through hole and is configured to be screw-fastened to a fastening hole of the outdoor unit case or the indoor unit case, or wherein the fixed unit comprises a hook projection and is configured to be hook-coupled to a hook hole of the outdoor unit case or the indoor unit case.