Is it possible to remove a EPC from flow shut down procedure on 8890?

Question

Is it possible to remove an EPC from flow shut down procedure of GC 8890? We are using EPC to stabilize sample line pressure at 3bar. When we are connecting new cylinders, we want to be sure that our pressure is slightly over 3 bar, so we set in the EPC to a higher pressure, and we use it somehow as a manometer. But during this procedure the 8890 shuts down the whole instrument due to low pressure. But there is no danger to any columns in the instrument as this EPC is controlling only the pressure of sample line. Is there any option to reprogram 8890 that it will not fall in the shut sown? 
 Tnak you 
 Petr

CMZainea · Answer

Hello Petr_Dohnal , 
 I&rsquo;m sorry for the delayed reply to your message. Do you still need assistance with this? If you do, please take into consideration the notes below. However, if the issue was resolved, could you please share what the resolution was? 
 Do you have a schematic of where the EPC is on the flow path? At this point I have a hard time understanding the role of the EPC. Is it controlling the front channel or the back channel? Based on your description it sounds like it doesn't control any inlet pressure, just the line pressure, but I don't know how that can be the case. Do you have the Part Number for the EPC?

CMZainea · Answer

Hello Petr_Dohnal ,

So, there are a couple things to unpack here. First, the 16 position selector autosampler, is that an Agilent ALS or a different model? Based on the description, I assume it's a non-Agilent ALS that requires gas line connection, in which case it would be something I am unfamiliar with. 
 In your case, it seems you are using the EPC outside of its intended use. My best suggestion/recommendation before going into an explanation would be to reach out to your local Agilent Team and have them physically check the setup for a more accurate answer. 
 
 That being said, this is what I can share with the information I have so far: 
 Generally, if you use an Agilent EPC, you need a Pressure differential of 20 psi (roughly 1.4 bar) between the EPC and whatever comes before that, which in this case seems to be the regulator. In other words, if you need an EPC to provide 4 bar of pressure, you need the regulator to be set at around 5.4 bar or higher. Any lower than that and this is quite possibly why you are getting the shutdown. 
 
 To answer your question in a vacuum, it is possible to remove the Readiness of some hardware components from the panel of the GC but as far as I can tell, you cannot do that for EPCs, only PCMs. Even if you could, I doubt it would solve your issue, as you would need to resolve the cause of the shutdown regardless. To explore the Readiness option, you can go to page 183 in the manual below. 
 Operation Manual (agilent.com) 
 
 Again, the approach I recommend is to reach out to your local Agilent Team for a more accurate assessment and solution.