A connector for connecting at least two receptor modules for a liquid medium, wherein the connector has a first connection end for the connection to a first receptor module and a second connection end for the connection to a second receptor module. The connector has a pressure equalization chamber between the first and second connection ends, in which a compressible insert is disposed. The compressible insert lies in part against the interior wall of the pressure equalization chamber. A least one longitudinal channel for a fluid communication between the first and second connection ends is provided between the interior wall of the pressure equalization chamber and the compressible insert. The compressible insert can be compacted as a result of a volume expansion of the liquid medium due to temperature conditions.