The solvent select manifold, within the Sample Manager, has an upper pressure limit that is protected by the instrument software. If this pressure limit is exceeded, the manifold may leak. This error message indicates that there is a blockage in the fluid path of the Sample Manager. The syringes of the Sample Manager are controlled by a feed back loop and will always attempt to keep the pressure below the upper pressure limit, but a total, or near total, blockage will make it impossible for them to move slow enough to keep the pressure below the threshold. The most likely suspects are the needle, the sample loop or the injector valve pod. I would work backwards from the needle. Disconnect the needle from the injection valve and perform a wash needle being careful to use a towel to collect the fluid that will exit the valve. If the syringes move at a normal, or fast, speed, then the needle is blocked and should be replaced. If the needle is not the problem, remove the sample loop and repeat the process (in the load position). Finally, disconnect the Volume Detection Device (the little black box) from the valve and see if the syringes react normally. If so, the valve pod has an issue. One word of caution, the Sample Manager is fairly intelligent. It will also monitor and report low pressure which indicate a lack of needle wash solvent. During your trouble shooting a low pressure error may be generated. Howevr, this will still indicate that you have correctly identified the blocked component.
I hope this is useful,
Unfortunately the SM has a blockage. It is probably needle, which should be checked first. It could be a blockage in the loop and less likely in the valve - so the fittings would need to be checked. Definitely, check the needle first.
It could be a pressure regulator failure, less likely - when did it happened, can you tell if it occurred during a wash or during the injection sequence.
The error message occurs as the pressure limit is 210 PSI. The diagnostic error messages are listed in the online help rather than the Operator's Guide as they do change.
Edited by: Elizabeth Hodgdon on Dec 17, 2008
I experienced the same issue with my Acquity. I would start up the system and during the purging of the syringes/needle washes the instrument would shut down and display that error. After days of troubleshooting I had narrowed the problem down to the Rheodyne High Pressure switching valve stator inside the UPLC. Apparently Waters/Rheodyne have a contract in which the valve parts are not replaceable so you have to purchase the entire unit through Waters. Called for service and the tech came out and replaced the entire valve. Long story short it fixed the issue.
Thanks for all the replies, the cause was probably to viscous solvent. We changed the solvent composition and do not experience the problem anymore.