A connecting arrangement for a fitting unit with a fitting housing (13). In the housing there is at least one bore (17, 18) for mounting a medium pipe (24, 36) by means of a threaded fitting 31, 34). The fitting may optionally be chosen as a nut (31) for squeezing a cutting sleeve 30) or as a soldering bushing (34) for mounting the medium pipe by soldering. Irrespectively whether there is a bore (17, 18) in the fitting housing or a bore in the soldering bushing 34), several parts with varying diameters would be provided so that medium pipes with different diameters can be fastened.