Freezers fail differently from coolers because ice is involved in both the problem and the symptom. A walk in freezer in Glendale, CA that has climbed above zero usually has a defrost fault, a low charge, or an evaporator so iced up that no air is moving across it.
JRC technicians thaw the coil properly rather than chipping at it, then find why it iced in the first place. Defrost heaters open circuit, termination thermostats drift, timers stop advancing, and door gaskets let warm humid air in that turns straight to frost. Fixing the ice without fixing the cause means we are back in three weeks, and neither of us wants that.