I have done all the repair diagnostics with regards to the Thermostat and Defrost heater. The freezer runs continuously. I have pulled the panel off the inside and noticed that after running for 4 hours that the top 1/3 of the coils have frost while the lower half is clear. The defrost heater did not feel warm however the thermostat was allowing voltage to the heater. Both had continuity. Could this be the result of a small leak in the system ? Or am I not checking it right? Door switch and gasket all were fine. Thanks