A dynamic receiver is included in parallel to an expander of a heating, ventilation, air conditioning, and refrigeration (HVACR) system. The dynamic receiver allows control of the refrigerant charge of the HVACR system to respond to different operating conditions. The dynamic receiver can be filled or emptied in response to the subcooling observed in the HVACR system compared to desired subcooling for various operating modes. The HVACR system can include a line directly conveying working fluid from compressor discharge to the dynamic receiver to allow emptying of the dynamic receiver to be assisted by injection of the compressor discharge.

A refrigeration system includes a rotary pressure exchanger fluidly coupled to a low pressure branch and a high pressure branch. The rotary pressure exchanger is configured to receive the refrigerant at high pressure from the high pressure branch, to receive the refrigerant at low pressure from the low pressure branch, and to exchange pressure between the refrigerant at high pressure and the refrigerant at low pressure, and wherein a first exiting stream from the rotary pressure exchanger includes the refrigerant at high pressure in the supercritical state or the subcritical state and a second exiting stream from the rotary pressure exchanger includes the refrigerant at low pressure in the liquid state or the two-phase mixture of liquid and vapor.

A gas-side stop valve on the gas refrigerant side and a liquid-side stop valve on the liquid refrigerant side are provided in a package of an outdoor unit. A gas-side filter on the gas refrigerant side is mounted on the indoor unit side relative to the gas-side stop valve and inside the package of the outdoor unit. A liquid-side filter 9 on the liquid refrigerant side is mounted on the indoor unit side relative to the liquid-side stop valve and inside the package of the outdoor unit. As a result, it is not necessary to ensure a place for mounting the gas-side filter and the liquid-side filter at the time of installation on site and the workability can be improved.

A method for monitoring a refrigerant charge in a vapour compression system (1) is disclosed, the vapour compression system (1) including a compressor unit (2), a heat rejecting heat exchanger (3), a high pressure expansion device (4), a receiver (5), at least one expansion device (9, 10), and at least one evaporator (11, 12) arranged in a refrigerant path. A change in net mass flow into or out of the receiver (5) and/or a change in net enthalpy flow into or out of the receiver (5) is detected, and a pressure inside the receiver (5) is monitored as a function of time, following the detected change in net mass flow and/or in net enthalpy flow. A time constant being representative for dynamics of the receiver (5) is derived, based on the monitored pressure as a function of time, and information regarding a refrigerant charge in the vapour compression system (1) is derived, based on the derived time constant.

A non-condensable gas purge system is configured to be used in a chiller system that uses a low pressure refrigerant in a loop refrigeration circuit. The non-condensable gas purge system includes a purge tank and a purge heat exchanger coil arranged inside the purge tank. The purge tank has a tank inlet for receiving the low pressure refrigerant from a condenser of the refrigeration circuit, a tank outlet for returning the low pressure refrigerant to an evaporator of the refrigeration circuit, and a purge outlet for purging non-condensable gas from the purge tank to the ambient atmosphere. The purge heat exchanger coil is fluidly connected to the loop refrigeration circuit such that the low pressure refrigerant contained in the loop of the chiller system can pass through the purge heat exchanger coil. Refrigerant in the purge tank is condensed by the heat exchanger coil while non-condensable gases remain gaseous.

The present disclosure relates to a method for controlling a level of superheat during a pump mode of operation of a refrigeration system, wherein the refrigeration system can operate in either the pump mode or a compressor mode, and has an electronically controlled expansion valve (EEV). A controller obtains a stored, predetermined pump differential pressure range able to be produced by a pump of the system. The controller also obtains a stored, predetermined superheat range, and detects a superheat level. When the detected superheat level is outside of the superheat temperature range, the controller commands adjusting at least one of the EEV and a speed of the pump based on whether the detected superheat level is above or below the superheat range, and whether a current pump differential pressure is above or below the predetermined pump differential pressure range.

A cryocooler includes a displacer, a cylinder that forms an expansion space, a Scotch yoke mechanism configured to drive the displacer in a reciprocating manner, a first rod that extends from the Scotch yoke mechanism, a housing that includes an assist chamber, a rotary valve configured to switch between a state in which the expansion space and a discharge side of a compressor are connected and the assist chamber and a suction side of the compressor are connected and a state in which the expansion space and the suction side of the compressor are connected and the assist chamber and the discharge side of the compressor are connected, a motor configured to drive the Scotch yoke mechanism and the rotary valve, and an on-off valve configured to open and close a gas flow path through which the rotary valve and the assist chamber are connected.

A heating, ventilation, air conditioning, and refrigeration (HVACR) protection system can include a pressure sensor operable to sense a pressure within a refrigerant line operably coupled to a compressor; a timer; and a protection system controller. The protection system controller can be in communication with the pressure sensor, the timer, and a compressor controller operable to control operation of the compressor. The protection system controller can disable the compressor controller from operating the compressor until successful completion of a vacuum test of at least the refrigerant line. The protection system controller can be configured to initiate the vacuum test upon the pressure sensor sensing the pressure of the refrigerant line less than or equal to a vacuum test pressure, at which point the timer begins timing for a vacuum test time period. The vacuum test can be successfully completed upon expiration of the vacuum test time period and the pressure of the refrigerant line remained less than or equal to the vacuum test pressure for the duration of the vacuum test time period. Additionally, the protection system controller can be configured to enable operation of the compressor controller to operate the compressor upon successful completion of the vacuum test.

The present application provides a vacuum pump (15) for use during maintenance or commissioning of an HVAC-R system (1). The vacuum pump (15) has a pump (17) having a pump intake (22) for connection to the HVAC-R system (1), in particular one or more of a high pressure service port (14) and a low pressure service port (13) of the HVAC-R system (1). The vacuum pump (15) also includes a communications unit (19) that is configured to connect to a mobile communications network. The vacuum pump (15) also includes a pressure sensor arranged to detect a pressure in the HVAC-R system (1). The vacuum pump (15) also includes a control unit (18) configured to receive pressure data from the pressure sensor (21), control operation of the pump (17), and communicate with a remote device via the communication unit (19) and the mobile communications network. In examples, the remote device (20) may be a mobile phone or a tablet computer, or any device that can connect to a mobile communications network. Therefore, the vacuum pump (15) can remotely communicate updates to the remote device (20) over a mobile communications network, and can optionally also receive instructions or requests from the remote device (20) over a mobile communications network.

A dynamic receiver is included in parallel to an expander of a heating, ventilation, air conditioning, and refrigeration (HVACR) system. The dynamic receiver allows control of the refrigerant charge of the HVACR system to respond to different operating conditions. The dynamic receiver can be filled or emptied in response to the subcooling observed in the HVACR system compared to desired subcooling for various operating modes. The HVACR system can include a line directly conveying working fluid from compressor discharge to the dynamic receiver to allow emptying of the dynamic receiver to be assisted by injection of the compressor discharge.