Mitsubishi Electric HVAC Advanced Products Division has launched a new program called Diamond Alliance, which provides priority recognition to distributors, dealers, contractors and engineers who complete various levels of system training. Each group has specific requirements to meet in order to be considered for priority status. The three groups making up the Diamond Alliance are known as Diamond Distributors, Diamond Dealers, and Diamond Designers. In early June, Contracting Business attended the Diamond Designer seminar program, a two-day event for Design/Build contractors and specifiers aimed at educating the mechanical system designer community on Mitsubishi’s new City Multi system. City Multi is an air conditioning system that simultaneously heats and cools and is designed for commercial and large residential applications. Diamond Designers receive the following benefits: priority listing on website for architects and building owner searches; advanced design training in all aspects of Mitsubishi Electric’s HVAC products including layout of system, software interface systems, controls design, operation of the system, design support, on-site support and start-up; an identification plaque for office display; and extended warranty protection (five years parts, 6 years compressor). City Multi Diamond Designers receive the “Request M” configuration software program that provides confirmation of indoor unit selection capacity ratio, identifies available components, draws system layout in AutoCAD, specifies pipe diameters, and identifies available components. Mitsubishi Electric says City Multi is the world’s first and only system that simultaneously heat and cools for up to sixteen indoor units with a total applied capacity of up to 150% of the outdoor units’ capacity. It’s a variable refrigerant flow zoning system that allows for superior part load efficiency. Equipped with an inverter-driven compressor (variable frequency drive), City Multi varies the capacity to meet indoor space load requirements while saving energy and providing indoor comfort. The City Multi R2 series condenser uses R22 refrigerants and capacity ranges for indoor air handlers are 8,000 to 48,000 Btus. Outdoor condensers have capacities of 80,000 and 100,000 Btus. The City Multi can be ducted or ductless, offering three indoor unit styles: PK series wall units, PL series cassette-type units, and PD Series concealed type indoor units with the ability to attach ductwork. Each indoor unit may have up to two remote controllers. The remote controllers allow the temperature setpoint to be changed, as well as the modes for heat/cool amd fan Controllers can be monitored and operated from a central controller or remotely through a computer including diagnostics capability through a web browser. Mitsubishi says the City Multi’s ability to zone each individual space makes it perfect for offices, schools, hospitals, assisted living facilities, hotels, and many other types of applications with productivity and comfort issues. For more information about Mitsubishi’s Diamond Alliance program or the City Multi system, visit