A vapor compression system includes a first conduit fluidly coupling a liquid collection portion of a condenser and an evaporator, where the first conduit is configured to direct a first flow of refrigerant from the condenser to a first inlet of the evaporator and a second conduit fluidly coupling the liquid collection portion of the condenser and the evaporator, where the second conduit is configured to direct a second flow of refrigerant from the condenser to a second inlet of the evaporator via gravitational force, and where the first inlet is disposed above the second inlet relative to a vertical dimension of the evaporator.

Embodiments of an accumulator for charge management are described. A fluid compression system, comprising an accumulator fluidly connected to an evaporator via a spillover port. The spillover port directs working fluid received from the evaporator to be collected and stored in the accumulator, where the stored working fluid is stored and released from the accumulator in response to an operating condition of the evaporator.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

A refrigeration system includes an evaporator configured to receive a flow of refrigerant and transfer heat into the refrigerant within the evaporator to provide cooling for a temperature-controlled space, an expansion valve operable to modulate the flow of refrigerant into the evaporator, a liquid level sensor configured to measure a level of liquid accumulated within a component of the refrigeration system, and a controller configured to operate the expansion valve to increase the flow of refrigerant into the evaporator or decrease the flow of refrigerant into the evaporator based on the level of liquid measured by the liquid level sensor.

A system for controlling a capacity of a compressor includes a motor of the compressor including a main winding connected at a connection point to an auxiliary winding and a drive configured to control a speed of the motor. The system includes a first switch configured to selectively connect the main winding to either a first line voltage or a first output of the drive, a second switch configured to selectively connect the connection point to either a second line voltage or a second output of the drive, and a third switch configured to selectively connect the auxiliary winding to either a capacitor or a third output of the drive. The system includes a solenoid valve configured to selectively either operate in a first capacity or a second capacity. The system includes a control module configured to control the drive, the first switch, the second switch, and the third switch.

A refrigerant charging device and a refrigerant charging system include a refrigerant charging flour path having a refrigerant charging port connected to a refrigerant flow path of an air conditioner, a valve provided at the refrigerant charging flow path, and a control device configured to control the valve. The control device includes a discharging superheat calculator configured to calculate the discharging superheat degree from a refrigerant temperature and a refrigerant pressure at a discharge side of a compressor, and a valve controller configured to control the opening and closing state of the valve based on the calculated discharging superheat degree calculated by the discharge super-heat calculator.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

A refrigerant measurement adjustment system includes: a refrigerant sensor for a building and configured to measure an amount of refrigerant present in air outside of a refrigeration system of the building; and an adjustment module configured to: adjust the amount of refrigerant measured based on an adjustment to produce an adjusted amount; and determine the adjustment based on at least one of: an air temperature; an air pressure; a relative humidity of air; a mode of operation of the refrigeration system; a change in the measurements of the refrigerant sensor over time; and whether a blower that blows air across a heat exchanger of the refrigeration system located within the building is on.

Thermal management systems are described. These systems include a refrigerant receiver configured to store a refrigerant fluid, an evaporator, a closed-circuit refrigeration system having a closed fluid circuit path, with the refrigerant receiver and evaporator disposed in the closed fluid circuit path, and the closed fluid circuit path including a condenser and compressor. These systems also include a modulation capacity control circuit configured to selectively divert refrigerant vapor flow to the condenser from the compressor by diverting a portion of refrigerant vapor flow (diverted flow) from the compressor to the refrigerant receiver in accordance with cooling capacity demand. These systems also include an open-circuit refrigeration system having an open fluid circuit path with the refrigerant receiver and the evaporator, and an exhaust line that discharges the refrigerant fluid from the exhaust line so that the discharged refrigerant fluid is not returned to the open-circuit and the closed-circuit refrigerant fluid flow paths.

A refrigeration system includes an evaporator configured to receive a flow of refrigerant and transfer heat into the refrigerant within the evaporator to provide cooling for a temperature-controlled space, an expansion valve operable to modulate the flow of refrigerant into the evaporator, a liquid level sensor configured to measure a level of liquid accumulated within a component of the refrigeration system, and a controller configured to operate the expansion valve to increase the flow of refrigerant into the evaporator or decrease the flow of refrigerant into the evaporator based on the level of liquid measured by the liquid level sensor.