Differences

This shows you the differences between two versions of the page.

--- wiki:design_construction [2022/02/02 17:14]
henri.godfrin@neel.cnrs.fr
+++ wiki:design_construction [2022/02/02 17:31]
henri.godfrin@neel.cnrs.fr
@@ Line 71: / Line 71: @@
   * Pumped 3He refrigerators have larger cooling powers that dilution refrigerators for T>0.35 K. The are also significantly more user friendly...
+===== Troubleshooting =====
+  * 1 K pot hot, pressure is low. Filling capillary blocked. Remove LHe so that the bath level is below the intake, keep 4He pressure in Pot above bath pressure. Having a heater on the 1K pot capillary can help, applying heat pulses...
+  * High inlet pressure. Air? Hydrogen? Water?
+  * Low still pressure. Still empty? Check T_still vs. P_still ! If there is no liquid, the pressure j
+  * is low, but the temperature is high.
+  * No cooling power. Interface level in MC? Heat leak to MC? Apply heat and check cooling power at higher temperatures. 3He/4He ratio OK?
+  * Heating spikes, temperature oscillations. Superfluid leak to Vacuum can? Check for spikes in the vaucum can pressure.

CryoTools