Subject: Comment raith SNF 2009-04-22 16:53:31: chilling loop repairs completed
From: jwc@snf.stanford.edu
Date: Wed, 22 Apr 2009 16:53:32 -0700

Neslab chiller was taken out of the cooling loop tested and found to be fine with full
flow on a simple Teflon hose loop.  > 4 lpm conductance.
Drained system by pressure back into output side removing a fair amount of debris from
the system cooling loop. 
Likely field service last week to this loop was a simply to drain and refill with no
pressure flushing.
Back flushed and forward flushed ~10 gallons of city water through the cooling loop
to the system and then drained completely.
Refilled with 50 grain acetic acid and pure water (5% acetic acid solution) and let
it circulate for two hours then drained and refilled with same concentration of this
solution.  The solution as it runs through the lines is now clear of particles and black
fungal debris. I am  continuing to recirculate  this solution through the system and
neslab chiller cooling loop overnight which should effectively descale any remaining
scale and debris.  Flow is currently set to 100 psi and 2.5 lpm.
Encountered several I/O and IEE-488 comm. issues on system start up and currently recalibrating
the X-Y-Z axis to the Lazer Interferometer Stage.  I am having problems with the Z motor
software limits and am troubleshooting this while I pump the system chamber down and
start the Ion Pumps. 
I hope have the system up and running for Users after 7 PM; albeit with reduced emission
and Beam I until the FE-Gun runs back in. 
Never a dull moment.
JWC