Andy, Is the ring-down-time normal. If not, then the optics need cleaning. There are cleaning instructions on the LGR website. Mark Haught -----Original Message----- From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Andrew Schauer Sent: Monday, February 09, 2009 3:16 PM To: [log in to unmask] Subject: [ISOGEOCHEM] LGR DLT100 Hi all, Have any of you LGR DLT100 liquid water analyzer owners taken it upon yourselves to attempt maintenance (beyond septum, filter, syringe)? Anybody know the software password? I like our LGR instrument. It is generally very reliable and provides wonderful dD data. We have had (for the second time in the last six months) a radical drop in water quantity. The first time, one of the two valves on the inside, malfunctioned. The entire instrument went back to LGR, was repaired, and ran until recently. Now, with a lack of response from LGR for help, I am getting ready to dive in. LGR is very secretive when it comes to this instrument which makes it very difficult to do-it-yourself. Thoughts? Thank you. andy Andrew Schauer ISOLAB Department of Earth and Space Sciences University of Washington Seattle, WA 98195 206.543.6327 [log in to unmask]