Delta Refrigeration, a Design Build contractor in Gabriel River Pkwy, Pico Rivera, California and National Engineers have announced a joint partnership so the National Engineers will provide MEP & General Engineering Services for Delta Refrigeration projects in the future. The two firms have recently completed a project for Southwind Food (a Seafood Product Company) in Carson California. The project scope was to convert two Central R-22 Systems (a low Temperature and a high temperature) to an R-507 & R-404 system.