An HVAC system includes a controller communicatively coupled to a subcool sensor, an outdoor temperature sensor, a compressor, and a blower of the HVAC system. For a first period of time, the controller periodically determines subcool values. For each determined subcool value, a corresponding compressor speed, outdoor temperature, and blower speed are determined. A baseline database is generated with baseline values associated with normal operation of the HVAC system. Following the first period of time, subcool values are determined based on the subcool signal. For each subcool value, a corresponding compressor speed, outdoor temperature, and blower speed are determined. The controller determines whether each subcool value satisfies a criteria based on the baseline database. If the criteria are not satisfied for at least a threshold time, the system is determined to be operating under a fault condition, and a corresponding alert is transmitted.

The technologies described and recited herein pertain to a permanent magnet motor having multiple voltage taps so that the motor may run in multiple configurations, e.g., a low-range and a high-range, and have multiple optimal operating points.

The various implementations described herein include methods, devices, and systems for cooling a vehicular electronics system. In one aspect, a vehicular refrigerant system includes: (1) a refrigerant loop having a compressor configured to compress a refrigerant, a condenser configured to condense the compressed refrigerant, an expansion device configured to enable expansion of the condensed refrigerant, and a heat exchanger configured to transfer heat from a liquid coolant to the expanded refrigerant; (2) a liquid coolant loop configured to transfer heat from an electronics system via the liquid coolant; and (3) a controller configured to: (a) obtain operating data regarding the refrigerant, the liquid coolant, and/or the electronics system; and (b) adjust operation of the refrigerant loop and/or the liquid coolant loop based on the obtained operating data.

A chiller system includes a compressor, a condenser and an evaporator in fluid communication. A motor drives the compressor. A variable speed drive powers the motor. An oil heater and pump system circulate heated lubricating oil in the compressor. A control panel is arranged to determine whether an input parameter is greater than or equal to a threshold parameter; deactivate the VSD in response to sensing that the input parameter is less than the threshold parameter; determine at least one chiller capacity control parameter at a point when the VSD is deactivated, and maintain the at least one chiller capacity control parameter while the VSD is deactivated; determine that the input parameter has been restored; determine a motor rotation and motor rotational speed; and in response to determining that the input parameter is restored and the motor is rotating in a forward direction, reactivate the VSD.

An air conditioning system can be toggled between a heating mode, in which heat is withdrawn from a source (e.g., a geothermal source) and deposited into a conditioned space (e.g., a building), and a cooling mode, in which heat is withdrawn from the conditioned space and deposited into the source. The air conditioning system uses a combination of efficiency-enhancing technologies, including injection of superheated vapor into the system's compressor from an economizer circuit, adjustable compressor speed, the use of one or coaxial heat exchangers and the use of electronic expansion valves that are continuously adjustable from a fully closed to various open positions. A controller may be used to control the system for optimal performance in both the heating and cooling modes, such as by disabling the economizer circuit and vapor injection when the system is in the cooling mode.

Disclosed are climate systems and methods for control the climate systems. A climate system includes a plurality of compressors, a first heat exchanger disposed downstream of the compressors and a second heat exchanger disposed downstream of the first heat exchanger. The compressors and heat exchangers are fluidly connected by refrigerant lines to form a refrigerant circuit. The climate system also includes a controller that controls the operation of the compressors to draw back lubricant to the compressors without use of an oil equalization system.

Embodiments of the present disclosure relate to an electronic identification system of a logic board for use in variable speed drives. Specifically, the present disclosure relates to a logic board for a variable speed drive having a configuration block that includes a plurality of resistors, a control system communicatively coupled to and configured to receive a signal from the configuration block, where the control system is configured to decode the signal to generate data indicative of an identity of the logic board, and a communication interface coupled to the control system, where the communication interface is configured to provide the data indicative of the identity of the logic board to an operator.

An HVAC system includes a face-split evaporator. The face-split evaporator includes a top evaporator circuit positioned above a bottom evaporator circuit. The system includes a first compressor associated with the top evaporator circuit, a second compressor associated with the bottom evaporator circuit, and a controller communicatively coupled to the first and second compressors. The controller receives a demand request, which includes a command to reduce power consumption by the HVAC system by a predefined percentage. In response to receiving the demand request, the second compressor is turned off thereby decreasing power consumption by at least the predefined percentage. A portion of a liquid condensate formed on a surface of the top evaporator circuit is allowed to fall on a surface of the bottom evaporator circuit such that a portion of a flow of air passing across the bottom evaporator is evaporatively cooled by the portion of the liquid condensate.

An HVAC system includes a compressor, condenser, and evaporator. A sensor measures a value associated with the refrigerant in the condenser or the evaporator, and a controller is communicatively coupled to the compressor and the sensor. The controller determines, based on an operational history the compressor, that pre-requisite criteria are satisfied for entering a sensor validation mode. After determining the pre-requisite criteria are satisfied, an initial sensor measurement value is determined. Following determining the initial sensor measurement value, the compressor is operated according to a sensor-validation mode. Following operating the compressor according to the sensor-validation mode for at least a minimum time, a current sensor measurement value is determined. The controller determines whether validation criteria are satisfied for the current sensor value. In response to determining that the validation criteria are satisfied, the controller determines that the sensor is validated.

A refrigeration appliance (2) is provided. The refrigeration appliance can comprise a fresh-food compartment (7) configured for storing food items at a first target temperature above zero degrees Celsius; and a freezer compartment (11) configured for storing food items at a second target temperature below zero degrees Celsius. A cooling air channel (27) is formed between the freezer compartment and the fresh-food compartment to allow air to flow between the freezer compartment and the fresh-food compartment. The refrigeration appliance further comprises a refrigeration circuit configured for cooling the freezer compartment, the circuit having a compressor, in particular a variable speed compressor, an evaporator, and a variable speed evaporator fan. A controller is operatively connected to the refrigeration circuit and configured to operate the variable speed compressor and/or the variable speed evaporator fan at a calculated speed of the variable speed compressor and a calculated speed of the variable speed evaporator fan, respectively; wherein the controller is configured to, in a normal mode of operation, operate the variable speed compressor at a first calculated compressor speed and the variable speed evaporator fan at a first calculated fan speed and wherein the controller is configured to, in a freezer priority, mode of operation, operate the variable speed compressor at a second calculated compressor speed and the variable speed evaporator fan at a second calculated fan speed, wherein the second calculated compressor speed is higher than the first calculated compressor speed and the second calculated fan speed is lower than the first calculated fan speed. Hereby an efficient control of the refrigeration appliance can be obtained wherein a quick-freezing mode can be supported that gives priority to the freezer in an efficient manner. Hereby items placed in the freezer compartment can be quickly frozen in an energy efficient manner.