Outer casing becomes excessively hot to touch during normal operation, not just around the lid and steam vent.

Safety first: If the exterior is too hot to touch comfortably, unplug the cooker and stop using it until inspected.

• Check ventilation: Ensure side and bottom vents are not blocked by towels, walls, or other appliances.
• Inspect internal insulation: Remove the outer housing to check for displaced or damaged insulation material around the cooking chamber.
• Reposition or replace insulation: If insulation has slipped, carefully reposition it. Replace any burnt or missing sections with suitable high-temperature insulation specified for the model.
• Verify shield placement: Ensure any reflective metal shields are correctly mounted and not bent away from the hot surfaces.

Because overheating of the casing is a safety concern, if you cannot restore proper insulation, have the unit serviced professionally.