I have a 7820A GC connected to a 5977B MS. When I submit a sample, it injects and runs as normal at first. Near the end of the run, an error message pops up that reads "Attempt to download method to GC failed." Additionally, when I check the logbook, there is an error message about vacuum system fault. I am confused by this since the sample was running fine and the pressure was being kept at the correct level by the vacuum.
Any advice on troubleshooting would be appreciated.
Verify that the system configuration is correct. Close the acquisition software and open Agilent GCMS Configuration, select the instrument, usually Instrument 1, and check the entries. Make sure that Enable Direct Communicaiton between instruments is NOT checked, as the 7820A GC does not support that option.
Open the acquisition software and load the default method. Use File, Edit entire method, and enter all of the proper parameters for your analysis, then save it as a new method with a new name. A corrupt method could be the cause.
Vacuum system faults depend on the type of high vacuum pump, turbomolecular or diffusion. These have different troubleshooting pathways. The turbomolecular pump either runs or does not run at 60,000 rpms. Their most typical failure mode is not starting up again after being shutdown. The diffusion pump has fluid in it that must be maintained. If the diffusion pump fluid is too low, the pumping speed is affected and can cause problems. Please look in the Troubleshooting and Maintenance Manuals for details.
