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 refrigeration cycle apparatus includes a compressor, a first heat exchanger, a second heat exchanger, a third heat exchanger, a flow path switching valve, a first expansion valve, a second expansion valve, a third expansion valve, a refrigerant container, a first check valve, and a second check valve. The flow path switching valve switches a circulation direction of a non-azeotropic refrigerant mixture between a first circulation direction and a second circulation direction. A first port of the third expansion valve communicates with the refrigerant container through the third heat exchanger. A second port of the third expansion valve communicates through the first check valve with a first flow path between the first heat exchanger and the first expansion valve, and communicates through the second check valve with a second flow path between the second heat exchanger and the second expansion valve.

In various implementations, frost in a vapor compression system may be controlled. A property of a fan may be determined. A determination may be made whether a frost event and/or a nonfrost event has occurred based at least partially on the determined fan property.

A hoseless sensor system for a refrigerant unit includes a plurality of hoseless sensors for sensing system parameters of the refrigerant unit, and a portable electronic device configured to receive the system parameters from the hoseless sensors and to calculate system conditions for the refrigerant based on the system parameters. The plurality of hoseless sensors includes a hoseless first pressure sensor and a hoseless second pressure sensor, and a hoseless first temperature sensor and a hoseless second temperature sensor. The temperature sensors may be temperature sensor clamps. Each temperature sensor clamp includes a clamping portion configured to clamp on a tube of the refrigerant unit, the clamping portion including a sensor element to measure temperature about the tube. The clamping portion further includes a plurality of clamping teeth, and adjacent clamping teeth interlock in an overlapping configuration when the clamp closes inward beyond a threshold point.

A predictive HVAC control apparatus and method, the predictive HVAC control apparatus having an input/output interface connected to a gain amplifier and a thermocouple amplifier, the gain amplifier connected to a first plurality of sensors disposed on an HVAC system, the HVAC system having HVAC system controls, and the temperature amplifier connected to a second plurality of sensors disposed on an HVAC system, a central processing unit connected to the input/output interface, and an HVAC control relay, connected to the input/output interface and the HVAC system controls.

An apparatus includes a high side heat exchanger, a second heat exchanger, a load, a variable speed compressor, and a three-way valve. The high side heat exchanger removes heat from a refrigerant. The second heat exchanger removes heat from the refrigerant. The load uses the refrigerant to remove heat from a space proximate the load. The variable speed compressor compresses the refrigerant from the load and directs the compressed refrigerant to the high side heat exchanger. The three-way valve, when operating in a first mode, directs the refrigerant from the high side heat exchanger to the load and when operating in a second mode, directs the refrigerant from the high side heat exchanger to the second heat exchanger.

A predictive failure system for a cooling apparatus having sensors measuring operational components of a cooling apparatus to determine performance data and means to analyze the data to determine a performance profile, wherein anomalies in the performance profile are determined and the operator of the cooling apparatus is warned prior to failure of the operational components.

The present disclosure relates to a refrigeration circuit that includes a controller communicatively coupled to a compressor, an expansion valve, and a sensor of the refrigeration circuit. The controller may activate the compressor and actuate the expansion valve such that the compressor is active while the expansion valve is closed. The controller may also measure a pressure of a refrigerant in the refrigeration circuit using the sensor while the compressor is active and the expansion valve is closed. Additionally, the controller may determine whether a refrigerant leak exists based on a maximum measurement time being reached or a time difference between a first time associated with the compressor being active while the expansion valve is closed and a second time associated with the measured pressure falling below a threshold value.

A vapour compression system (1) including a compressor unit (2) having at least one main compressor (3) and at least one receiver compressor (4), a heat rejecting heat exchanger (5), a receiver (7), an expansion device (8) and an evaporator (9) being arranged in a refrigerant path. The vapour compression system (1) further includes a bypass valve (12) fluidly interconnecting the gaseous outlet (10) of the receiver (7) and the main compressor(s) (3). A pressure difference across the bypass valve (12) is measured or derived, and a mass flow rate of refrigerant through the bypass valve (12) is derived, based at least on the pressure difference across the bypass valve (12), and using a fluid model. A minimum mass flow rate of refrigerant required to operate the receiver compressor (4) is derived, based on a minimum displacement volume of the receiver compressor (4) and using a fluid model taking prevailing operating conditions into account. In the case that the derived mass flow rate of refrigerant through the bypass valve (12) exceeds the derived minimum mass flow rate of refrigerant required to operate the receiver compressor (4), the receiver compressor (4) is started and the bypass valve (12) is closed.

Provided are a refrigeration heat reclaim unit and method, comprising a heat exchanger, comprising a refrigerant inlet that receives a flow of refrigerant having a first state; a refrigerant outlet that outputs the flow of refrigerant having a second state; a water loop inlet that receives a flow of liquid at a first temperature; a water loop outlet that outputs the flow of liquid from the reclaim heat exchanger at a second temperature that is greater than the first temperature in response to the flow of refrigerant. The refrigeration reclaim unit also comprises a refrigerant flow control device having outputs to the refrigerant inlet and an air-cooled condenser, respectively for controlling the flow of refrigerant to at least one of the refrigerant inlet and the air-cooled condenser for maintaining a predetermined flow quality value at the refrigerant outlet.