Integrated air conditioning and water-harvesting systems are disclosed. In these systems, one subsystem (air conditioning or water-harvesting) may be a primary subsystem and the other subsystem may be a secondary subsystem. As load on the overall system increases to the point the cooling demands for both subsystems cannot be met simultaneously, the system automatically reduces output of the secondary subsystem. In certain embodiments, an atmospheric water-harvester may be connected into the (potentially pre-existing) chilled-water system that provides cooling throughout a building, either via distributed fan-coil units or a centralized air-handling unit. Additionally, providing cooled-air exhaust from an atmospheric water-harvester to a building's cooling system allows substantial quantities of water to be produced at nominal incremental operating cost over a simple, straightforward air conditioning system.

A multi-zone vapor compression system (MZ-VCS) includes a compressor connected to a set of heat exchangers controlling environments in a set of zones, a supervisory controller determining a set of control inputs for controlling a vapor compression cycle of the MZ-VCS, and a set of capacity controllers. The supervisory controller is a model predictive controller (MPC) determining the set of control inputs using a model of the MZ-VCS including a linear relationship between thermal capacities of each heat exchanger and temperatures in a corresponding zone controlled by the heat exchanger. Each capacity controller enforces the linear relationship between the thermal capacity and the temperature in the corresponding zone.

A comfort control system includes a user-end subsystem and a system-end subsystem. The user-end subsystem includes an environmental control device, a sensor and a communication apparatus. The environmental control device adjusts an environmental factor value of a predetermined area. The sensor senses an activity value of a user. The communication apparatus sends the activity value and an identifier corresponding to the user. The system-end subsystem includes a communication element, a comfort database and a computing apparatus. The communication element receives the identifier and the activity value. The comfort database includes a basic data table having a physiological value and a preference data table having a control parameter. The computing apparatus looks up the basic data table for the physiological value and looks up the preference data table for a corresponding control parameter. The computing apparatus controls the environmental control device to adjust the environmental factor value.

An air-conditioning apparatus has a controller that sets the target value of a difference between the temperatures of a secondary-side heat transfer medium at positions before and after a plurality of use side heat exchangers during a rated operation in a heating operation so as to have a larger magnitude than a target value of the difference between the temperatures of the secondary-side heat transfer medium at positions before and after the plurality of use side heat exchangers during a rated operation in the cooling operation.