| 1000 | Fill LN2 coldtrap full. Mixing chamber temperature at 79.1 |
| 1440 | Commence pumping mixture to dump. Pump out He gas line. |
| 1445 | Start LN2 blowout with background leak rate at 1.0e-8 mbar*L/s. |
| 1600 | End LN2 blowout. Leak rate raised steadily to 7.4e-8 mbar*L/s, though no spikes occurred to indicate a leak. |
| 1610 | Start pumping on main bath. |
| 1625 | Stop pumping on main bath. Conduct throughput test with background leak rate of 6.4e-8 mbar*L/s. Throughput test showed a flow rate of ~21 mbar/min, with a background leak rate decreasing to 4.8 mbar*L/s. Throughput test repeated with background rate of 4.3e-8 mbar*L/s; no indication of leak and flow rate of ~21 mbar/min found again. Close condenser line and gate valve, and pump mixture to dump. |
| 1655 | Evacuate the 1K Pot. Pump out gasline and flush main bath with He gas. Add 4.0e-2 mbar He exchange gas. |
| 1755 | Start LHe transfer (0.0%). Mixing chamber temperature at 78.8 K. |
| 1845 | Notice that we have been using N2 to pressurize dewar instead of He. Cease transfer immediately, remove transfer stick, shut off He recovery. He level reader reads 99.9% but quickly drops to 94.5%. Troubleshooting determines that He gas is flowing from the LHe dewar check valve and gas input valve, as well as from transfer stick port on main bath. This suggests that frozen N2 has not blocked ports on LHe dewar (what a relief). Mixing chamber temperature still reads 78.8 K. Turbo pump pressure gauge reading 4.6e-3 mbar, though that might not be correct. |
| 1945 | With temperature in mixing chamber still not dropping, consult with Vuk and add more He exchange gas to IVC. Add until pressure gauge reads 3.4 mbar. Mixing chamber temperature immediately begins dropping from 78.8 K. He level meter also begins dropping. |
| 2000 | With mixing chamber temperature below 60 K (Nitrogen freezing point) it is now assumed safe to resume He recovery. |
| 2030 | Due to unknown levels of He exchange gas, exchange gas was pumped out at mixing chamber temperatures of 12 K. Within 10 minutes the mixing chamber reached a minimum temperature of 4.8 K before increasing slightly. He level meter has settled at 60.2%. |
| 2110 | Fill LN2 cold trap full. Commence cryocleaning mixture through cold trap 2. |