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Historically we have had more trouble with cooling Dewar A down than Dewar B. Dewar A has taken more than 3 days in the past and this most recent time (March '23) its taken about two weeks. 
This is likely just because the settings were not optimized for cooling and we had better pay more attention to the system setting for switching between production and cooling modes. If the pressure in the dewar is greater than that on the cold heads the dewar will never cool and the system enters a perpetual state where the cold heads are cold but the dewar is warm.
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