The vacuum behaved erratic over night with excursion up into the mid 10^-6 Torr range. To investigate the chamber was vented. With the doors open, the o-rings and sealing surfaces were cleaned. When pumping down again a vacuum leak could be heard at the front door by the lock. The chamber was vented again twice, finally the two o-rings were swapped. This removed the large leak. The door is prevented from contacting the box at the lock, which is likely the source of the leak.