A system and method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack and determines compressor rack power consumption data. A condensing unit controller monitors and controls operation of the condensing unit and determines condensing unit power consumption data. The system controller receives the compressor rack power consumption data and the condensing unit power consumption data, determines a total power consumption of the refrigeration or HVAC system, determines a predicted power consumption or a benchmark power consumption for the refrigeration system, compares the total power consumption with the predicted power consumption or the benchmark power consumption, and generates an alert based on the comparison.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.

A pressure control device for controlling a compressor includes a pressure sensor configured to measure pressure of a pressure line and a processing circuit. The processing circuit is configured to receive the measured pressure of the pressure line from the pressure sensor and control the compressor based on a set-point and the measured pressure. The pressure control device includes a mechanical switch sensitive to the pressure of the pressure line and configured to move between an open position and a closed position responsive to the pressure of the pressure line. Movement of the mechanical switch into one of the open position or the closed position causes the compressor to turn off and overrides the control of the compressor by the processing circuit.

A system and method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack and determines compressor rack power consumption data. A condensing unit controller monitors and controls operation of the condensing unit and determines condensing unit power consumption data. The system controller receives the compressor rack power consumption data and the condensing unit power consumption data, determines a total power consumption of the refrigeration or HVAC system, determines a predicted power consumption or a benchmark power consumption for the refrigeration system, compares the total power consumption with the predicted power consumption or the benchmark power consumption, and generates an alert based on the comparison.

An illustrative example refrigerant system includes a compressor configured to pressurize a refrigerant fluid. The compressor includes a sump portion. A heater is situated to heat at least the sump portion. A controller is configured to selectively operate the heater to apply heat to at least the sump portion while the compressor is off to establish and maintain a superheat condition in the compressor.

A method for controlling a refrigeration system having a compressor, heat rejecting heat exchanger, expansion valve and heat absorbing heat exchanger circulating a refrigerant in series flow, the heat absorbing heat exchanger in thermal communication with working fluid, the method includes obtaining an expansion valve position set point; using a feedback control loop to generate a controlled expansion valve position; obtaining a rate of change of an operating parameter of the system; using the rate of change of the operating parameter to generate an adjustment; modifying the controlled expansion valve position using the adjustment; and controlling the expansion valve using the modified controlled expansion valve position.

Methods and systems for detecting and correcting improper operation of a compressor in a refrigeration system and/or an HVAC system include a component level detection and prevention and a system level detection and prevention. The system level detection and prevention can be a backup or a confirmation of the component level detection and prevention. The component level detection and prevention can detect and prevent improper compressor operation within a predetermined time so that the compressor's operation period in an improper direction can be minimized, thereby minimizing wear and damage to the compressor.

A system and method of controlling temperature of a medium by refrigerant vaporization, the system including a container, at least one a refrigerant reservoir having at least one reservoir section that includes a wall with an exterior surface structured to be thermally coupled with a volume of the medium in the container and to provide a volume of medium thermal coverage in the container, a vapor pressure apparatus to provide regulation of refrigerant vapor pressure in the at least one refrigerant reservoir, whereby the refrigerant reservoir forms a vapor space in each of the at least one reservoir section in response to receiving refrigerant and to the vapor pressure apparatus regulation of vapor pressure above the refrigerant to enable refrigerant vaporization at or near a selected temperature of the volume of medium in the container that is thermally coupled to the respective reservoir section.

Methods and systems for providing control of a heat pump of a motor vehicle are presented. In one operating mode, speed of a heat pump compressor is controlled responsive to an outlet pressure of the heat pump compressor. In a second operating mode, speed of the heat pump compressor is controlled responsive to a pressure ratio between an inlet and an outlet of the heat pump compressor.

An economizer includes a separation wheel, a motor, and a liquid storage portion. The separation wheel is arranged and configured to separate refrigerant into gas refrigerant and liquid refrigerant. The separation wheel is attached to a shaft rotatable about a rotation axis. The motor is arranged and configured to rotate the shaft in order to rotate the separation wheel. The liquid storage portion is arranged and configured to store the liquid refrigerant. The economizer is adapted to be used in a chiller system including a compressor, an evaporator and a condenser.