- Switch the LIquefier to Manual + Liquefy mode (Manual + Idle mode is also the same because Liquefy/Idle option has no effect when it is in the 'Manual' mode)
- Ensure the dewar pressure alarm threshold is around 0.2 psi (navigate to the Liquefier 'Settings' to check that).
- Set the inlet flow to 60slm: enter 60slm on FC501(A/B)Q (then press enter)
- Set the outlet flow for the maximum flow by opening SVV(A/B) and the manual hand valve bypassing the SVN(A/B)
Note: Currently, this bypass valve exists only for LQ-B (will install one for LQ-A soon) - Turn ON the cold heads manually on "Helium Compressors" screen
- It will take about 2 hrs and 30 mins for the cold head temperatures to reach 4 Kelvin.
- Once cold head temperatures reach 4 Kelvin, then gradually close the SVNB-bypass hand valve while watching the Dewar pressure.
Reason: because the Dewar pressure would be ~1psi at this stage and we want to bring the Dewar pressure up so we can transition to have the outflow through SNVB (with the flow controller), and stop the flow through SVVB. - Once the Dewar pressure is > 6.5 psi from Step 7, then close SVVB and immediately open SVNB and ensure the FCBQMC is 60slm (FCBQ will also show 60slm).
- Then you will see FCBI starts increasing and should go up to 60slm or, at least 40slm (or above).
- Let it run in this configuration: in-flow 60slm, out-flow 60slm (via SVNA/B), cold-heads are running, mode: run+manual+liquefy
- You should expect ice/frost on Dewar neck during this phase, and you will have to use the heat gun to melt the frost.
- When you start seeing FCBI start going down while FC501B is 60slm, then lower the value of FCBQMC step by step based on the FCBI.
- Once you bring FCBQMC down < 5slm, then check the Liquefier Settings screen to ensure the following values.
- Switch the Liquefier to Run + Auto + Liquefy mode
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