Not long after I got that squared away I noticed the compressor for the refer unit was switching on more frequently than usual and that the temperature didn’t stay regulated very well.  I had a friend that works on refrigeration come out and the culprit was coolant was basically gone.  So he refilled the unit with 409A and it worked well for one year.   Meanwhile, (and I need to try and get a good photo of this, difficult due to reflection from the window) an oily residue started to exude from the window gasket in the box.  This happened despite the fact that I was only using minor amounts of deuterated benzene for NMR work as the only volatile material allowed inside the box!  When I brought these problems up to Innovative Technology, Inc. they had nothing useful to say nor did they offer to fix the problems.