Proper sealing and insulation of display cases and merchandisers are critical for maintaining optimal temperature and humidity conditions. Ensure that all doors and lids are properly aligned and sealed, and that any gaps or openings are filled with appropriate sealants. Insulation materials such as foam or fiberglass should be installed according to the manufacturer’s specifications, and regular inspections should be conducted to detect any signs of wear or damage. Additionally, consider using automatic door closers and threshold seals to minimize air leakage.