Hello, does anyone know if the G7111B quaternary has a recommended minimum operating pressure? We have recently tried running an in-house PQ and had some random changes in peak shape. An in-house restriction capillary (length of peek tubing) rather than column is used and the back pressure is ~13bar. My suspicion is the pump is not working optimally at this low pressure, but so far Google has let me down. The other make/model of LCs we have typically have a back pressure ~30bar using the same setup.
