A pipe arrangement for geothermal probes includes at least two pipes having at least one layer each that surrounds a lumen. One of the pipes functions as inflow pipe and the other pipe functions as return flow pipe. At least one of the pipes is produced at least in part from a non cross-linked polymer material and is distinguished in that the polymer material of the at least one layer for the pipes has a FNCT value (full notched creep test) according to ISO 16770 of at least 3000 hours.