Each component of the City Multi, a variable refrigerant flow zoning (VRFZ) system, is integrated through the City Multi Controls Network (CMCN). The CMCN consists of remote controllers, timers, system controllers, centralized controllers, building management system interfaces, and integrated software that provide control for each zone of a building. The M-Net communication bus consists of two nonpolar wires that are daisy-chained between components. The two-wire, nonpolar, stranded, shielded wire is connected from the outdoor unit to the branch circuit (BC) controller, from the BC controller to the first indoor unit, and then cascades between indoor units. Depending on the type of zone remote controller, it can be connected anywhere on the communication bus or directly to an indoor unit. Each indoor unit can be controlled by one or two remote controllers, which allow the user to adjust the temperature setpoint, the heat-cool operation mode, the fan speed, the vane direction, and turn on and off the unit.
Mitsubishi Electric, HVAC Advanced Products Div., Attn: Mike Smith, Marketing Manager, 4505-A Newpoint Place, Lawrenceville, GA 30043; 800-687-1966; 678-376-3540(fax); www.mehvac.com.