DavecUK xcellent, I have updated the blog article on the forum. I think there is a general lack of knowledge out there about the regular maintenance and O ring replacement requirements of these flow controls.
DavecUK The following message would probably be more effective as a reply to your FAQ post (but there is no reply option), or as a new thread. I leave it up to you to move wherever if you see fit:
I just pulled the first shot after servicing the flow control device and replacing the O-rings and I was completely shocked by the result. Not only was the action of the valve so much smoother, I was actually able to control the flow completely, stop it, hold the pressure where I want it and get instant reaction from the manometer - all things that I was NEVER able to achieve before!
Until today, when I tried to almost close the device for pre-infusion a few seconds after lifting the lever, I could slow the ramp up a little, but that was about it. Then when I would tale off the pressure to end a shot, there was a delay in reaction and I would usually go down to about 6 bar to end the shot. I saw videos of people holding pressure for long periods (at 2-4 bar for example). In those videos, manometer reacted instantly to closing/opening of the valve. Mine didn’t do that, and I just assumed that my machine/flow control device are ‘different’. What a fool I was! I now realise that when I first got the device I damaged the O-rings by opening the valve too much. The valve probably never sealed completely since then, so I was only able to make small changes to the flow, but not control it completely. With the new O-rings and some lube, I finally get to play with the flow control device as it should be (I hope I am not getting carried away here - this was just one shot and I still have to play and confirm the above, but couldn’t resist sharing already). For anyone who is as stupid as me, your FAQ is priceless.
