Norcold cooling problem

The freezer cools great and usually to 0 to 10 degrees because IT is the first evap plate the CU tubes run thru. Then it goes down to the lower evap plate. The Lower evap plate is where the tstat regulates lower cooling. There is NO regulation of the freezer cooling. AND, any CU blockage is AFTER the Freezer coils. That is why people think they have a good refer, because the freezer does so great. BUT!!!!! Freezing is anything below 32 degrees. Unless you get an accurate Thermometer reading on the freezer, then HOW would you be able to tell 15 degrees as opposed to 22 or 10 or 26 degrees> It ALL seems cold. AND, Frozen items in the freezer will KEEP the freezer temp a long time, even if you have a control problem. Doug