I disconnected the thermistor and let it hang as Doug suggested and ran it overnight at max setting of 5. the refer temp was down to 31 degrees and the freezer was down to 0. The outside temps were cooler last night about 60 degrees. The average fin temp was 20 degrees. I noticed that refer temp seems to be about 10 degrees higher than the fin temps in running these tests. I called Norcold for a replacement part number but they said the refer was obsolete and could not find a replacement part for it, they wanted me to buy a newer 1200 model. Does anyone know of a replacement thermistor and part number and where to buy one? I would just like to cut the end off and splice to the old wires and clip it back to the fin.