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Hey Bjoern,

I'm definitely not familiar with re-aligning the cavity.  Seems like you
would actually need manufacturer equipment to do that.  Definitely a
changing the oil vs. transmission rebuild situation.

As far as recommendations concerning repair vs. repurchase I think that all
depends on your situation and future goals.  If you only see yourself
needing to get data for a small amount of time/samples then maybe just a
repair?  I'm not sure how much a new similar Picarro is but a comparable
LGR model to what I have is roughly $60k so you would be paying a third of
a new machine to have a much older machine hopefully keep working?  Maybe
they have a trade in policy so you can get the price of a new one lowered a
bit if you intend to keep running samples into the extended future.

Good luck!

Vince

On Wed, Apr 12, 2017 at 3:46 PM, mwolhowe . <[log in to unmask]> wrote:

> Ah, yes actual spec problems in the cavity are well outside my purview.
> There are some less serious issues I've resolved myself, so I had my
> fingers crossed. Good luck!
>
> Dr. Matthew Wolhowe
> Postdoctoral Research Fellow
> University of Washington School of Oceanography
>
> On Wed, Apr 12, 2017 at 3:04 PM, Bjoern Wissel <[log in to unmask]>
> wrote:
>
>> Hello Vince,
>>
>>
>>
>> Thanks for your suggestions. The actual diagnosis (see below) is a slight
>> misalignment in the cavity as well as a minor leak. We can fix the leak
>> part in-house (damaged thread on the intake nut, which are Swagelok
>> components) but the cavity repair is supposed to be done at the factory.
>>
>>
>>
>> Cheers, Bjoern
>>
>>
>>
>>
>>
>>
>>
>> *When looking at your instrument it seems that there might be a slight
>> miss alignment in the cavity.  When running further test I was able to scan
>> the spectra and it looks like it is mostly effecting your 18 O region.
>> With this a slightly miss alignment in the optical components will create a
>> shadow or doublet of the measured spectra.  I originally thought that since
>> your instrument was off it would disappear,  I also looked at trying to
>> remedy the issue by increasing your threshold but you are already at the
>> maximum.  Unfortunately this means that your instrument must come back for
>> a cavity repair.  If you do not wish to send back the instrument you can
>> use it but we cannot guarantee out spec on the COC form.  I would try to
>> run a drift test to find out what your current precision is.  If you are
>> okay with your precision you are able to still use the instrument.  Please
>> let me know your thoughts.*
>>
>>
>>
>>
>>
>> --
>>
>> Björn Wissel, PhD
>>
>> Associate Director, Institute of Environmental Change and Society
>>
>> Adjunct Professor, Department of Biology
>>
>> 525 Research and Innovation Centre
>>
>> University of Regina
>>
>> Regina, SK S4S 0A2 Canada
>>
>> phone    306 585-4890 <(306)%20585-4890>
>>
>> fax      306 337-2410 <(306)%20337-2410>
>>
>> e-mail   [log in to unmask]
>>
>>
>>
>> www.iecs-uregina.ca
>>
>> www.uregina.ca/biology/index.php?page=faculty/Wissel2
>>
>>
>>
>> *From:* Stable Isotope Geochemistry [mailto:[log in to unmask]] *On
>> Behalf Of *Randall Debes
>> *Sent:* April-12-17 3:50 PM
>> *To:* [log in to unmask]
>> *Subject:* Re: [ISOGEOCHEM] Picarro L2120i CRDS question
>>
>>
>>
>> Hi Bjorn,
>>
>>
>>
>> I don't have a Picarro CRDS, I'm using a LGR CRDS circa 2010 so the
>> actual physical schematics might be different but the technology is
>> similar.  I've been troubleshooting for instrument for years so I might be
>> able to give some direction.
>>
>>
>>
>> What exactly are the issues?  You mentioned H2O concentration, does that
>> mean the injection volume is changing during the run? How are the d18O
>> values changing?  Does it seem like instrumental drift?
>>
>>
>>
>> The concentration could be a matter of clogged lines, faulty syringes, or
>> a leak in the plumbing somewhere (maybe a faulty/sticking valve).  I have
>> replaced my sample transfer line and filter many times because the samples
>> I am running are high in dissolved silica so it builds up in the system.
>> You might want to clean the injection block as well.
>>
>>
>>
>> As for the cavity replacement, unless the mirrors are broken or
>> scratched, I don't think that is really necessary.  I have cleaned the
>> mirrors on my instrument which helped with odd d18O drift.  Picarro
>> probably has a procedure for this, LGR did and they even sent me a kit with
>> everything I needed to do it myself.
>>
>>
>>
>> I've been keeping my instrument alive myself for years due to lack of
>> "send it to LGR" money as well.  LGR and Picarro tout these instruments as
>> "rugged, reliable, and field ready" but more and more I think that
>> description is more meant for the first couple years after purchase.
>>
>>
>>
>> Cheers!
>>
>>
>>
>> Vince
>>
>>
>>
>> On Wed, Apr 12, 2017 at 11:18 AM, mwolhowe . <[log in to unmask]> wrote:
>>
>> Bjorn-
>>
>> What's the actual diagnosis? I've had to fix some things myself due to
>> "send it in to Picarro" money not being there, as has a colleague of mine
>> with even more experience. So far Picarro support has been pretty helpful
>> with leading me through the do-it-yourself options, but maybe it's
>> something one of us has experience taking care of?
>>
>> Dr. Matthew Wolhowe
>>
>> Postdoctoral Research Fellow
>>
>> University of Washington School of Oceanography
>>
>>
>>
>> On Wed, Apr 12, 2017 at 10:05 AM, Andrew Schauer <
>> [log in to unmask]> wrote:
>>
>> Hi Björn,
>>
>>
>>
>> We now budget for this sort of repair as it has happened to us once. I
>> wonder if we should be thinking of these instruments more as modern smart
>> phones and computers where we can't expect more than 5 years out of them.
>> So sad.
>>
>>
>>
>> andy
>>
>>
>>
>> On Wed, Apr 12, 2017 at 8:14 AM, Bjoern Wissel <[log in to unmask]>
>> wrote:
>>
>> Dear list members,
>>
>>
>>
>> We have been using a Picarro L2120i water analyzer since 2012. In total
>> we probably analyzed about 5000 samples (incl. standards), at eight
>> injections each. Most samples are from Canadian prairie lakes which have
>> slightly elevated salinity of up to 1 to 2 psi.
>>
>>
>>
>> Recently, we ran into an issue that effects H2O concentration and del18O
>> measurements. After diagnosis we are looking at a $20K fix/replacement of
>> the cavity and a downtime of several months.
>>
>>
>>
>> Based on the age, model and use of the instrument I am trying to gauge if
>> a repair is warranted of if we should rather invest in a new CRDS.
>>
>> I would greatly appreciate any comments, experiences, suggestions
>> regarding this issue.
>>
>>
>>
>> Thanks and all the best, Bjoern
>>
>>
>>
>>
>>
>> --
>>
>> Björn Wissel, PhD
>>
>> Associate Director, Institute of Environmental Change and Society
>>
>> Adjunct Professor, Department of Biology
>>
>> 525 Research and Innovation Centre
>>
>> University of Regina
>>
>> Regina, SK S4S 0A2 Canada
>>
>> phone    306 585-4890 <(306)%20585-4890>
>>
>> fax      306 337-2410 <(306)%20337-2410>
>>
>> e-mail   [log in to unmask]
>>
>>
>>
>> www.iecs-uregina.ca
>>
>> www.uregina.ca/biology/index.php?page=faculty/Wissel2
>>
>>
>>
>>
>>
>>
>>
>> --
>>
>> Andrew Schauer
>> 206.543.6327 <(206)%20543-6327>
>> [log in to unmask]
>> *http://isolab.ess.washington.edu/ <http://isolab.ess.washington.edu/>*
>>
>>
>>
>>
>>
>>
>>
>> --
>>
>> Randall (Vince) Debes
>>
>> Research/Lab Aide
>>
>> Arizona State University
>>
>> School of Earth and Space Exploration
>>
>> Tel: 4802205918 <(480)%20220-5918>
>>
>
>


-- 
Randall (Vince) Debes
Research/Lab Aide
Arizona State University
School of Earth and Space Exploration
Tel: 4802205918