I came to the campus and Gautam notified that he just had received the alert from the vac watchdog.
I checked the vac status at c1vac. PTP3 went up to 10 torr-ish and this made the diff pressure for TP3 over 1torr. Then the watchdog kicked in.
To check the TP3 functionality, AUX RP was turned on and the manual valve (MV in the figure) was opened to pump the foreline of TP3. This easily made PTP3 <0.2 torr and TP3 happy (I didn't try to open V5 though).
So the conclusion is that RP for TP3 has failed. Presumably, the tip-seal needs to be replaced.
Right now TP3 was turned off and is ready for the tip-seal replacement. V5 was closed since the watchdog tripped.