A refrigeration cycle apparatus includes a refrigerant circuit, by pipes, connecting a compressor, a flow switching device, a first heat exchanger, an expansion device, and a second heat exchanger. As refrigerant to be circulated through the refrigerant circuit, any one of a refrigerant having saturated gas temperature under standard atmospheric pressure that is higher than that of R32 and a refrigerant mixture mainly composed of the refrigerant is used. The refrigerant circuit includes an internal heat exchanger configured to exchange heat between the refrigerant flowing through a refrigerant-inlet side of the second heat exchanger and the refrigerant flowing through a refrigerant-outlet side of the second heat exchanger.

A rotary compressor system includes a compressor housing that includes a compressor motor that draws in fluid from a suction side. The fluid is compressed within a compression chamber and discharged through a discharge side. The compression chamber is disposed between the suction side and the discharge side. An overload-protection switch is electrically coupled in series with the compressor motor and is adapted to cut power to the compressor motor responsive to an overload event. A solenoid valve is fluidly coupled between the compression chamber and a location upstream of the suction side and is electrically coupled in series with the overload-protection switch. An interruption of electrical current to the compressor motor also interrupts electrical current to the solenoid valve, which opens the solenoid valve to equalize pressure between the suction side and the discharge side.

The unloading of multi-stage compressors may include the introduction of flow from a gas bypass from a condenser into a second-stage inlet duct to induce a swirl in the flow into second stage compression. This unloading may be performed on multi-stage compressors in heating, ventilation, air conditioning and refrigeration (HVACR) circuits that include a gas bypass from a condenser to the second-stage inlet housing of the compressor. The multi-stage compressor may include an impeller inlet duct including a flow straightener receiving fluid flow from the first stage discharge, and one or more channels to introduce gas from the gas bypass into the flow passing through the impeller inlet duct. The flow introduced by the channels may have a direction of flow including a component opposite to the direction of flow of the fluid flow from the first stage discharge via the flow straightener.

A refrigeration system for cooling an object and preventing system overheating. The system includes an evaporator coil configured to thermally communicate with the object, where the object is cooled by a refrigerant flowing through the evaporator coil. A compressor receives the refrigerant downstream from the evaporator coil and increases a pressure of the refrigerant. A condenser receives the refrigerant downstream from the compressor, where the refrigerant is cooled by flowing through the condenser. An expansion valve receives the refrigerant downstream from the condenser and decreases the pressure of the refrigerant, where the evaporator coil receives the refrigerant downstream from the expansion valve. An bypass coolant valve also receives the refrigerant downstream from the condenser. The compressor also receives the refrigerant downstream from the bypass coolant valve, and the refrigerant received by the compressor from the bypass coolant valve bypasses the evaporator coil to prevent overheating of the compressor.

A heat pump system for a vehicle comprises a heating, ventilating, and air conditioning module as well as a refrigerant circuit including a compressor, an internal condenser, and an external condenser. The module comprises a warm air path including the internal condenser, a cold air path formed independently from the warm air path, a purge flow path branching from the warm air path at a position downstream of the internal condenser with respect to a flow of air through the module, and a purge control door adjustable between a first position preventing fluid communication between the warm air path and the purge flow path and a second position allowing fluid communication between the warm air path and the purge flow path. The purge flow path provides fluid communication between the warm air path and the ambient environment.

A method for operating an elasto-caloric heat pump includes running the elasto-caloric heat pump with a pre-strain in an elasto-caloric stage of the elasto-caloric heat pump set to an initial pre-strain setting, and gradually shifting the pre-strain in the elasto-caloric stage of the elasto-caloric heat pump set away from the initial pre-strain setting and towards a final pre-strain setting over a time interval.

The present disclosure is directed to a single compressor HVAC system with hot gas reheat. The system includes a single compressor, a pair of condensers, a reheat heat exchanger, an evaporator, and an expansion device. Within the system, the refrigerant exiting the compressor is separated into two portions. In the cooling mode, the first and second portions of the refrigerant are directed from the compressor through the two condensers in parallel. In the reheat mode, the first portion of the refrigerant is directed through the first condenser, while the second portion of the refrigerant is directed through the reheat heat exchanger. The system also may include a head pressure control device that is designed to maintain the compressor discharge pressure within a desired range by adjusting the condenser fan speed.

A refrigerant loop of a vapor injection heat pump includes a compressor, first and second expansion valves, and first and second separator valves. The separator valves allow an entire refrigerant flow to pass therethrough or operate to separate vapor and liquid components of expanded refrigerant and inject the vapor component into a suction port of the compressor. Vapor injection occurs in both heating and cooling modes of operation and may depend upon an ambient condition (e.g., high or low ambient temperatures). An accumulator receives an output refrigerant of the heat exchangers dependent upon the mode and directs a vapor component into another suction port of the compressor. A control module controls at least the first and second expansion valves and first and second separator valves dependent upon the mode of operation which include, among others, heating, cooling, and dehumidification and re-heating.

An apparatus for heating water has a tank for storing water and an air conditioning system that defines a refrigerant flow path through which refrigerant flows. The refrigerant flow path passes through the heat exchanger so that refrigerant heat is contributed to the tank. A control system controls operation of the water heating apparatus.

The present invention relates to a refrigerant circuit for a refrigerator and/or freezer, with at least one body and with at least one cooled interior space arranged in the body, wherein the refrigerant circuit includes at least one evaporator and at least one condenser as well as at least one compressor, wherein the condenser is partly or completely arranged in a liquid bath that at least partly absorbs the condensation heat in operation of the refrigerant circuit.