A sealing arrangement for a coupling for refrigerant lines comprises a first coupling piece, which is connected sealingly to a first line end piece, and a second coupling piece which is connected sealingly to a second line end piece. In the sealing arrangement, a sealing ring is held on the sealing face of one of the two coupling pieces by a holding device which is configured as a plastic cap having a through hole. The plastic cap has at least one predetermined breaking location (26) which is configured as a groove which reduces the material thickness of the plastic cap in such a way that the material integrity at the predetermined breaking location (26) is maintained during assembly and breaks apart during disassembly.