Key Highlights Sub-Zero freezers utilize a cycle defrost system, not a self-defrosting one. This specialized system minimizes frost buildup and eliminates the need for manual defrosting. Sub-Zero freezers use electric heaters to gently warm the coils and melt any frost, which is then drained away. While not entirely maintenance-free, the system significantly reduces the frequency ... https://sub-zero-appliance-repair.com/demystifying-do-sub-zero-freezers-defrost-themselves/