The refrigerator car, commonly called a reefer, provides active temperature control for perishable commodities during transit. Mechanical reefers use diesel-powered refrigeration units mounted in an end compartment to circulate cooled air throughout the load chamber. Cryogenic reefers use liquid nitrogen or liquid carbon dioxide instead of a mechanical compressor for longer retention times or ultra-cold requirements. Modern mechanical reefers maintain temperatures from -20 degrees Fahrenheit to +70 degrees Fahrenheit with precision control.
Self-contained diesel refrigeration unit in end compartment; capable of multi-temperature zones and precise setpoint control over long distances.
Liquid nitrogen or CO2 system for frozen commodities; simpler mechanically but requires cryogen servicing at intermediate points on long hauls.
Heavy plug doors provide superior insulation compared to sliding doors; standard on modern mechanical reefers to minimize thermal leakage.
Refrigerator cars handle transcontinental movements of fresh produce from California and Florida to eastern markets, as well as frozen meat and dairy products moving between processing facilities and distribution centers.