R409A, an HCFC-based refrigerant, is a cost-effective retrofit refrigerant for R-12 stationary positive displacement air-conditioning and refrigeration systems such as walk-in coolers, beverage dispensers, vending machines, and supermarket systems. No oil change is needed in many unitary and close-coupled systems.

places
R-12
Applications
Medium- and low-temperature positive displacement equipment in supermarket systems and walk-in coolers. 
Benefits
Works with existing mineral oil (MO) in many unitary and close-coupled systems.
Alkylbenzene (AB) oil is recommended for optimum oil return.