Chromatography Forum

Please help me. I have a Micro 490 that is used to analyze and monitor commercial natural gas supplied to natural gas engines. As a Quality Manager that has limited knowledge of the process, I am at a loss and the Technical guy we had here has left without completing the documentation that I requested on this unit for Preventative Maintenance (Bake-out sessions) or calibration. The operations documentation was completed and we have been running, however we have noticed the BTU of samples has started to drift. We ran calibration gas through and realized that we are starting to see small shifts in the readings. We have looked at the past information of the previous employee and realized that we must be coming due for a "Bake-Out" session. I have been searching through what documentation we have and sent e-mails to Agilent (waiting on a response). I would like to get this out of the way ASAP to ensure this unit if functional for items we need to do this week. Can someone with experience with this model tell me where to look for the prepared bake-out method? I have looked through the options, but still do not see it. I assume I must load a method and run it to help clean the columns. Can anyone help?

Since the machine was configured at the factory for this analysis, I would assume a cal to technical service at Agilent would be helpful.

If that does not help, the instrument should be baked out at a temperature well below a temperature that might damage the columns. Since I assume a Hayesep U capillary is installed I would suggest overnight at 150C might be a good choice. But confirm this with Agilent before you do anything. They may have components that might not tolerate such temperatures.

Rod