Abstract: A diagnostic apparatus for analyzing a motor of a heating, ventilation, and air conditioning (HVAC) system. The diagnostic apparatus includes a portable control unit which is detachably coupled to the HVAC system. The control unit can monitor, generate and simulate all control functions associated with the HVAC system.

Abstract: A diagnostic apparatus for analyzing a motor of a heating, ventilation, and air conditioning (HVAC) system. The diagnostic apparatus includes a portable control unit which is detachably coupled to the HVAC system. The control unit can monitor, generate and simulate all control functions associated with the HVAC system.

Abstract: A system and method of controlling airflow within an air delivery system. The method begins by identifying and measuring a particular air conditioning system's blower characteristics. A mathematical relationship for finding a particular CFM based on torque and speed is developed utilizing several discrete airflows within regions or bins within a designated range. The mathematical model is employed by a controller of the air conditioning system for controlling CFM. Additionally, the method may optionally change from an airflow control mode to a blower speed or torque control mode when restrictions are placed upon the air conditioning system.

Abstract: A thermostat that includes a subbase having a back surface designed to be mounted conformal with a surface and an inner surface that has a portion of selected electrical components mounted thereon, including a first electrical communication device. The subbase has first mechanical connectors formed integral therewith. A cover that has a front surface designed to carry selected components for communication with an operator and an inner surface that has a portion of selected electrical component supported thereby, including a second electrical communication device. The inner surface has second mechanical connectors formed integral therewith. During installation, the cover is brought into registry with the subbase to form a thermostat housing that has a reduced profile and that substantially encloses the electrical components of the thermostat.

Abstract: A self configuring air conditioning system. The system includes a system controller for an air conditioning system operably connected to a compressor and an expansion valve, a first portable wireless remote controller for providing commands and information to the system controller by wireless transmission, and a second portable wired remote controller for providing commands and information to the system controller by wired transmission. The system further includes a wireless receiver operably connected to the system controller for receiving wireless remote transmissions from the first portable wireless remote controller, and an interface operably connected to the system controller for receiving wired remote transmissions from the second wired remote controller.

Abstract: In a variable speed air conditioning system driven by an electronically commutated DC motor, the large DC capacitor associated with the compressor motor drive discharges to the normally AC powered compressor oil sump heater upon the loss of AC power to the system.

Abstract: A variable capacity refrigeration system includes a control scheme having three interrelated closed loops. The system includes a refrigeration system controller and at least one variable speed, electronically commutated DC motor driving a compressor. In the first closed loop, the controller supplies a speed command signal to a motor drive which governs the speed of the motor driven compressor. The speed of the compressor varies the system's capacity to condition the temperature of a comfort zone. A temperature sensor in the zone provides a temperature feedback signal to the controller to complete the first closed loop. In the second closed loop, the speed command signal from the controller is varied in response to a speed feedback signal received from a compressor drive which includes both the motor and the motor drive. The third closed loop is between the motor drive and the motor.

Abstract: A microcomputer based defrost control for a heat pump system that "learns" from previous defrost cycles to achieve optimum defrost control at each of a plurality of outdoor temperature ranges, even if the heat pump system operating parameters change due to system aging. At the conclusion of each defrost cycle, the control determines the differential temperature between the outdoor ambient air and the outdoor heat exchanger and compares that value to a value stored in microcomputer memory representing a previous best such post-defrost differential temperature for the same ambient air temperature range. The control then calculates a defrost differential temperature initiate value, corrected to compensate for any loss of defrost performance indicated by the current post-defrost cycle differential temperature.