A refrigerant cycle system includes a primary-side cycle that circulates a first refrigerant, a secondary-side cycle that circulates a second refrigerant, and a cascade heat exchanger that exchanges heat between the first refrigerant and the second refrigerant. The primary-side cycle includes a primary-side connection pipe. The secondary-side cycle includes a secondary-side connection pipe. The primary-side connection pipe includes a primary-side gas connection pipe and a primary-side liquid connection pipe. The secondary-side connection pipe includes a secondary-side gas connection pipe and a secondary-side liquid connection pipe. The pipe diameter of the secondary-side gas connection pipe is smaller than the pipe diameter of the primary-side gas connection pipe, or the pipe diameter of the secondary-side liquid connection pipe is smaller than the pipe diameter of the primary-side liquid connection pipe.

A lubricant reservoir for a compressor, which can be part of a system of a heat pump, in particular, a high-temperature heat pump, having a holding chamber for lubricants with at least one holding-chamber cladding element at least partially outwardly limiting the holding chamber, and a temperature controller is integrated into the holding-chamber cladding element and/or arranged on it, wherein a heating and/or cooling medium can flow through the temperature controller, which may achieve an improved life cycle assessment in such a lubricant reservoir compared to the known systems, reduce the production or assembly effort, and enable lubricant cooling and lubricant heating.

A heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a first compressor having a first capacity, a second compressor having a second capacity, a condenser, an expansion device, and an evaporator fluidly connected. The first compressor and the second compressor are arranged in parallel. The first compressor includes a first lubricant sump. The second compressor includes a second lubricant sump. The first lubricant sump is fluidly connected to the second lubricant sump via a lubricant transfer conduit. A flow restrictor is disposed in the lubricant transfer conduit. The flow restrictor is configured to reduce a refrigerant flow between the first compressor and the second compressor.

Disclosed is a screw compressor (100), comprising a screw compressor housing (101), a discharge cavity (113), at least one silencing channel, and at least one adjustment piston, wherein the discharge cavity (113) is defined by at least one part of the screw compressor housing (101); the at least one part of the screw compressor housing (101) defining the discharge cavity (113) forms a wall of the discharge cavity (113); at least one hole is provided in the wall of the discharge cavity (113); the at least one adjustment piston can be inserted into the at least one hole and move therein; the at least one silencing channel is formed by the at least one hole and the at least one adjustment piston, and the at least one silencing channel is in fluid communication with the discharge cavity (113); and the position of the at least one adjustment piston in the at least one hole determines the silencing length of the at least one silencing channel.

A heat pump is provided with a compressor; an oil separator provided on a discharge path of the compressor; an accumulator connected to the compressor via a suction path; and a bypass circuit configured to supply a gas refrigerant separated by the oil separator. The bypass circuit is connected to the suction path.

An air conditioning apparatus includes an electric compressor, an inverter, a temperature detection element, and an ECU. The electric compressor compresses a refrigerant drawn from a refrigerant intake port and discharges the refrigerant from a refrigerant discharge port. The inverter is integrated with the electric compressor so as to be cooled by the drawn refrigerant, and operates the electric compressor according to a control signal. The temperature detection element detects a temperature of the inverter. The ECU outputs a control signal to control the inverter. The ECU performs any one or both of a control for reducing a self-cooling amount of the electric compressor and a control for increasing a self-heat generation amount of the inverter with respect to the inverter when the temperature detected by the temperature detection element is lower than a predetermined reference temperature.

Disclosed is a hermetic AC electric motor that includes harmonics shunting such that high frequency harmonics are shunted from the AC electric motor without the use of one or more high frequency filters in the associated motor drive. A related method of operating an AC electric motor includes shunting high frequency harmonics to a fluid passing through the AC electric motor. Also disclosed is a simplified variable speed motor drive system which eliminates the need for a filter for removing high frequency harmonics.

A refrigeration system that induces lubricant-liquid refrigerant mixture flow from a flooded or falling film evaporator by means of the lubricant-liquid refrigerant mixture flow adsorbing heat from an electronic component.

A crankcase heating control system for a heat pump system includes a data receiving module and a power control module. The data receiving module receives data indicative of a temperature of a compressor of the heat pump system, data indicative of an ambient temperature, and data indicative of a current date and a current time. The power control module selectively applies power to a heater of a crankcase of the compressor and selectively disables the heater based on the temperature of the compressor, the ambient temperature, the current date, and the current time.

A method of cooling a motor coupled to a compressor of a chiller includes adjusting a position of a motor cooling valve located fluidly between the motor and a refrigerant source, using a motor temperature control system coupled to the motor cooling valve to regulate an amount of refrigerant introduced into the motor from the condenser according to a temperature control scheme performed as a function of a monitored temperature in the motor, a first temperature threshold, and a second temperature threshold lower than the first temperature threshold. The temperature control scheme includes a motor cooling control process that adjusts the position of the motor cooling valve based on a stator winding temperature set point relating to stator windings of the motor. A proportionally limited close command override associated with a first temperature range above the second temperature threshold proportionally limits a close command provided to the motor cooling valve.