Dear Isotopers:

I have difficulty to find a L-N2 sensor position to satisfy both -120 C 
and -170 C for our Kiel device. I moved up and down the sensor mm by mm,
still couldn't find a good spot, either too high or too low. A defect
sensor, or thermostat or other reason?

I saw the machine trying three times to get to -120C. It might work if I
can set it to try four or  five times. Is that recommended? If so, how can
I change the setting?

Thanks for help.

Dachun Zhang
ESS Dept, UCI