The solenoid was found to be warm on Monday morning. M9Q3 had a bad water 
leak over the weekend. The water header serving Q3 was turned off and the 
leak confirmed. Q3 was isolated and the header was turned back on. My 
supposition is that while the main header was turned off, the diff. pump 
under the solenoid tripped. When I looked at it this morning the 
compressor was off and the vesssel vacuum was very bad. The PLC connection 
to EPICs is down, so I can not restart the vacuum system yet. Mike Leross 
is looking at the problem. 
There was no trip signal to the main control room. It looks as though the 
control room signal was bypassed downstairs. 
The power supply fault light was on on the QRL panel, but I okayed Bob 
Hilton locking out the power supply in order that Q3's water leak can be 
repired. Shutting of the main breaker may have turned on this light. The 
other possibility is that the power supply was not ramped down and shut 
off properly.