Abstract: A compressor may include a shell, orbiting and non-orbiting scrolls, an unloader bushing assembly and a drive shaft. The unloader bushing assembly may include a drive bushing and a spring. The drive bushing includes an outer surface engaged with the orbiting scroll and may define an opening extending from a first bushing end to a second bushing end. The spring may include a body disposed within the opening of the drive bushing and may include first and second spring ends with at least a portion of the first spring end extending laterally from the body and overlapping the first bushing end. At least a portion of the second spring end may extend laterally from a body and overlap the second bushing end to secure the spring within the drive bushing. The drive shaft may include a crank pin disposed within the opening of the drive bushing and engaging the spring.

Abstract: A method of operating a heating, ventilation, or air conditioning (HVAC) monitoring service is described. The method includes: providing a local device for installation in an HVAC system of a residential or commercial building; periodically receiving data from the local device across a wide area network, wherein the received data includes electrical sensor data including at least one of current or power; and storing the received data. The method further includes: analyzing the stored data to selectively identify problems and selectively predict faults of the HVAC system; receiving a subscription fee corresponding to the building, the subscription fee applying to a calendar period; and during the calendar period, providing information on the identified problems and the predicted faults to a customer corresponding to the building.

Abstract: A monitoring system for monitoring operation of a refrigerant-cycle system is disclosed. A differential pressure sensor measures a pressure difference between: (i) air at a first location upstream of an evaporator of the refrigerant-cycle system; and (ii) air at a second location downstream of the evaporator of the refrigerant-cycle system. An electrical sensor measures an electrical quantity indicative of power consumption of the refrigerant-cycle system. A processing system determines whether airflow through the evaporator is restricted based on the pressure difference. The processing system calculates an efficiency of the refrigerant-cycle system based on the power consumption of the refrigerant-cycle system.

Abstract: A method of operating an electric motor is disclosed. The method includes: starting the electric motor in an open loop control mode; operating an estimator that estimates operating conditions of the electric motor; and, while the electric motor is in the open loop control mode, evaluating a first parameter of the estimator. The method further includes: in response to the evaluation of the first parameter, determining whether the estimator has converged; and in response to a determination that the estimator has not converged within a predetermined period of time after starting the electric motor, signaling a first fault condition.

Abstract: Disclosed are working fluid compositions for heat transfer apparatuses, such as refrigeration systems, that include a refrigerant and an ester based lubricant. The working fluid may comprise ?50% by weight of the ester based lubricant composition and ?50% by weight of one or more refrigerant compounds. The ester based lubricant comprises an additive selected from the group consisting of: diaryl sulfides, arylalkyl sulfides, dialkyl sulfides, diaryl disulfides, arylalkyl disulfides, dialkyl disulfides, diaryl polysulfides, arylalkyl polysulfides, dialkyl polysulfides, dithiocarbamates, derivatives of 2-mercaptobenzothiazole, derivatives of 2,5-dimercapto-1,3,4-thiadiazole, and combinations thereof.

Abstract: A bearing housing may include a body portion, a hub, and a thrust bearing. The body portion may include a radially inwardly facing first annular surface. A structure may extend radially outward from the body portion. The hub may extend axially from the body portion and may include a radially inwardly facing second annular surface adapted to rotatably support a shaft. The thrust bearing may extend axially from the body portion and may include an outer surface, a thrust surface, an inner surface, and an undercut feature formed in one of the inner and outer surfaces. The undercut feature may define a cantilevered portion of the thrust bearing.

Abstract: A system includes a refrigerant compressor including an electric motor, a current sensor that measures current flow to the electric motor, a switching device configured to close and open to allow and prevent current flow to the electric motor, respectively, a maximum continuous current (MCC) device that includes a resistance corresponding to a maximum continuous current for the electric motor, and a motor protection module. The motor protection module communicates with the MCC device, the current sensor, and the switching device and determines a first MCC value for the electric motor as a function of the resistance of the MCC device. The motor protection module also selectively sets a predetermined MCC to the first MCC and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A system is provided and may include a refrigeration circuit having a condenser, a first sensor producing a signal indicative of a detected condenser temperature of the condenser, and processing circuitry in communication with the first sensor. The processing circuitry may determine a derived condenser temperature independent from information received from the first sensor and may compare the derived condenser temperature to the detected condenser temperature to determine a charge level of the refrigeration circuit.

Abstract: A sensor module for a compressor having an electric motor connected to a power supply is provided. The sensor module includes an input that receives current measurements generated by a current sensor based on a current of the power supply. The sensor module also includes a processor. The processor is connected to the input, determines a maximum continuous current for the electric motor, and selectively compares the current measurements with a value equal to the maximum continuous current multiplied by a predetermined value. The maximum continuous current is set based on at least one of a type of refrigerant used by the compressor and actual refrigeration system conditions.

Abstract: A sound enclosure for enclosing a compressor assembly in an assembled state can include at least one cover piece, a shoe member, and a base. The shoe member can include a partial circumferential wall that projects upright from a generally planar portion. One of the partial circumferential wall or the cover piece has a projected portion. The other of the partial circumferential wall or the cover piece has a recessed portion. In the assembled state, the projected portion nests into the recessed portion. The base includes an outer contact area. The shoe member includes an outer perimeter. In the assembled state, the outer contact area is in contact with the outer perimeter of the shoe member.

Abstract: A compressor diagnostic device is provided and includes at least one of a temperature sensor and a current sensor. The current sensor measures a first current flow through a motor of a refrigerant compressor. The temperature sensor is disposed within and sensing a temperature of a measurement region of an electrical conductor that is configured to close and open to allow and prevent current flow to the motor, respectively. The compressor diagnostic device also includes a controller in communication with the at least one of the current sensor and the temperature sensor. The controller is operable to control the electrical conductor based on a comparison of a second current flow through the motor and a maximum current.

Abstract: A three-phase electric motor of a compressor receives first, second, and third phases from a three-phase power supply. A method for protecting the motor includes, using a line break protector, disconnecting the motor from only the first phase in response to a temperature being greater than a predetermined temperature threshold. The method also includes measuring a first current flowing through the line break protector, and determining a current value based on the first current independent of current in the second and third phases. The method further includes disconnecting the motor from the first, second, and third phases in response to the current value being less than or equal to a predetermined threshold.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate having a plurality of ports, a header, and a plurality of cylinders disposed within the header. A plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and permitting flow through the plurality of ports and into the compression mechanism and a second position engaging the valve plate and restricting flow through the plurality of ports and into the compression mechanism. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a different diameter than the other of the chambers.