When the fridge is in Hold Cold Mode, it means we have a liquid in the fridge nose and holding target material. In that case, we must keep the target material to preserve the paramagnetic centers. In the Hold Cold Mode, you will see the fridge parameters as follows:
We fill the fridge to Heat-Ex Top for the Cold Hold Mode and close the Run and Bypass valves. To reduce LHe consumption in the fridge nose, set the GV bypass opening at 8.1% at the lowest opening to keep the fridge pressure flat. Set the Separator flow at 11slm.
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