The laser has since tripped since being brought back. Attached is a plot of the laser power and
diode chiller temperature. It looks like the loss of cooling capacity coincides with the laser
tripping. Even with no heat load, the water temperature of the diode chiller has not come down
in the last 30-40 minutes.
Prepping to sub in the spare chiller.
This looks very familiar to the failure that occurred at LLO last week with the a failure of the controller operating the hot gas valve bypass. If the chiller is still on, have a feel of the hot gas valve line and see if its scorching hot like we found it to be here. This was because the hot gas valve solenoid would just stay constantly on, thereby heating up the water and throwing the DB overtemp fault.
Note I have found out from Technotrans that we can not just swap controllers between chillers, even chillers of the same model. The are software coded for a unique S/N of a chiller.
I am currently in the process of getting spare controllers for LHO, so if LHO can provide me with a list of the S/Ns of the chillers they want to have a spare controller for (I only asked for two controllers) I can pass that info on to my technotrans spare parts rep.