50-plus-year old Kelvinator chest 14 ft3 freezer.

Question

The temp control unit is no longer available.  I bought (nonreturnable) one that controls from 1F to 20F thinking I could keep it at 1F.  But the temp is -18F at the lowest setting.  Any suggestions?  Two repairmen told me I should keep the freezer as long as possible.  I am not sure why they suggested that I keep it.Harry [e-mail]