This is what the cooling tube looks like behind the fin plate. <
The COLDER part of the cooling tube is at the top. The Extreme cold comes from the freezer tubes and then down. It flows to one side at the top of the evap plate, makes a 180 degree curve and flows to the bottom back of the evap plate. The Thermister is installed inside that plastic clip on the flat fin. The Evap fins will be 10 degrees colder than the inside of the refer. If the evap fins are 26 degrees the inside of the refer will be 36 degrees. Sliding it up and down on a NON adjustable Tstat refer will only yield at best a 4 degree temp difference. The Thermister senses the FIN TEMP, NOT Air temp. Doug