Switching Cold Traps Mid-Circulation

If the pressure in G2 begins to rise while the mixture is circulating, this may be an indication of a dirty cold trap. You can switch to the other cold trap, if it's clean, by following the process below.

1. Assuming that cold trap 1 is currently being used, the valves on the left hand side of the IGH that should be opened are: V1, V6, V13A, and V12A. Open V13B to allow mixture into the cold trap 2 to cool it down. Let the mixture settle in there for about a minute.
2. Open V12B. This brings cold trap 2 into circulation.
3. Close V13A. This stops cold trap 1 from having mixture circulated through it.
4. Close cold trap 1's speedivalve on the back of the IGH.
5. Close V12A. Make a note of the value of P1.
6. There is some mixture left in cold trap 1 that needs to be pulled back into circulation. Confirming that the vent speedivalve and V7 are both closed, open V11A and V8. Monitor the pressure increase in P1. Take a note at what value P1 maximized. Once P1 has reached a stable value and is similar to what it was before switching cold traps, you can close V8 and V11A.