Display Case Service
Servicing commercial display cases including open and closed merchandisers, temperature ranges for different product types, evaporator fan motor service, and diagnosing air curtain failures.
- Identify display case types and their operating temperature ranges for various product categories
- Diagnose evaporator fan motor failures and air curtain disruptions in open display cases
- Service condenser coils, drain systems, and door gaskets on closed display merchandisers
- Measure and verify product temperatures comply with food safety requirements
Lesson 1
Display Case Types and Temperature Requirements
Categories of Display Cases
Light commercial display cases are the front line of food merchandising in convenience stores, gas stations, delis, bakeries, and small grocery operations. Unlike supermarket rack systems, these units are typically self-contained with their own compressor, condenser, and evaporator in one cabinet.
Display Case Styles
Open multi-deck cases expose product on multiple shelves with no door or cover. An air curtain of cold air flows from the top to the bottom of the case opening, creating an invisible barrier between the cold interior and the warm store air. These cases use the most energy and are most sensitive to airflow disruptions.
Glass door merchandisers have insulated glass doors that customers open to access products. These are far more energy efficient than open cases because the doors prevent constant air infiltration. They are common for beverages, frozen foods, and dairy in convenience stores.
Deli/bakery cases are horizontal display cases with a flat or curved glass top. Product sits on a cold plate or in a refrigerated well, and a small fan circulates cold air to maintain temperature.
Air Curtain Sensitivity
Open display cases rely on a precise air curtain to maintain product temperatures. Any disruption to the air curtain - blocked discharge grilles, failed evaporator fans, product stacked above the load line, or drafts from nearby HVAC vents or doors - allows warm store air to infiltrate and raises product temperature above the safe 41 degrees F limit.
The FDA requires cold-held foods below 41 degrees F - open display cases maintain temperature through an air curtain that is easily disrupted by blocked grilles, failed fans, or product stacked above the load line.