The HPO survived overnight without any problems.

This morning the HPO was turned off to allow for testing of the pre-modecleaner setup
with the front end laser.  After that was completed the HPO was turned back on.  After
being on for ~20 minutes, a leak developed in both flow meters leading to turning the
HPO off (the flow meters being for the power amplifier and the power meters).  Replacement
of the water manifold is in progress.  Fortunately no damage was done to the HPO.

Examination of the MOPA flow meter showed a large rust stain on the flow meter body.
In retrospect this partly explains why in recent weeks the topping up of the crystal
chiller was occurring more frequently.  In the short time between turning off the laser(s)
and the chillers, the flow meter for cooling the power meters leaked water profusely.
Examination of that flow meter showed a break in the body.

It should be noted that the flow meters, which are part of the water manifold, are located
on the floor under the PSL table and are typically not inspected every day.

The spare water manifold is being prepped for installation.  In doing so it was noticed
that there were a number of material strands left from when the threads were tapped.  As
many of these were removed as possible, thereby reducing the possibility of one of the
coming loose and jamming up the plumbing else where in the system.



Jason, Peter