A refrigeration cycle apparatus in which a refrigerant having potential for disproportionation reaction circulates a first refrigerant flow path connected between a discharge side of the compressor and the condenser; a second refrigerant flow path connected between the condenser and the expansion valve; a third refrigerant flow path connected between the expansion valve and a suction side of the compressor; a jetting unit; a pressure measuring unit; and a temperature measuring unit. The jetting unit is configured to jet the refrigerant drawn from the second refrigerant flow path or the third refrigerant flow path to at least one of the compressor, the first refrigerant flow path and the second refrigerant flow path when at least one of a measured value of the pressure measuring unit and a measured value of the temperature measuring unit exceeds an allowed value.

Methods and systems for detecting and correcting improper operation of a compressor in a refrigeration system and/or an HVAC system include a component level detection and prevention and a system level detection and prevention. The system level detection and prevention can be a backup or a confirmation of the component level detection and prevention. The component level detection and prevention can detect and prevent improper compressor operation within a predetermined time so that the compressor's operation period in an improper direction can be minimized, thereby minimizing wear and damage to the compressor.

This invention relates to of a cooling device (1) comprising a compressor (2) which compresses the refrigerant fluid, a condenser (3) which enables the superheated vapor exiting the compressor (2) change to first a liquid-vapor phase then liquid phase entirely, a compressor cabinet (8) positioned separately from the cooling cabinet (7), into which the compressor (2) and the condenser (3) are positioned, one or more evaporators (4), and one or more capillary tubes (5) interposed between the compressor cabinet (8) and the evaporator (6), and a control method thereof.

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.

An air-conditioning apparatus includes: a refrigeration cycle; an injection circuit for connecting between an injection port and a branching portion arranged between an indoor expansion valve and a main circuit expansion valve; an injection circuit expansion valve arranged in the injection circuit; an internal heat exchanger for exchanging heat between refrigerant flowing between the branching portion and the main circuit expansion valve and refrigerant depressurized by the injection circuit expansion valve; and an outdoor unit control device, the outdoor unit control device being configured to control an opening degree A of the main circuit expansion valve so as to satisfy Relation A+C=BGr, where A represents the opening degree of the main circuit expansion valve, C represents an opening degree of the injection circuit expansion valve, B represents a coefficient, and Gr represents a refrigerant circulating amount in the refrigeration cycle.

A system and method for flooded start control of a compressor are provided. An ambient temperature sensor generates ambient temperature data and a compressor temperature sensor generates compressor temperature data. A control module receives the ambient temperature data and the compressor temperature data, determines whether the outdoor ambient temperature is rising faster than the compressor temperature, determines whether the outdoor ambient temperature is greater than the compressor temperature by more than a predetermined threshold for more than a predetermined time period, and, in response to the outdoor ambient temperature rising faster than the compressor temperature and the outdoor ambient temperature being greater than the compressor temperature by more than the predetermined threshold for more than the predetermined time period, operates the compressor according to at least one cycle including a first time period during which the compressor is on and a second time period during which the compressor is off.

A system includes a control module and a monitor module. The control module selectively operates a component of the system in an ON state. The system receives power from an electrical grid. The monitor module selectively detects a fault event of the electrical grid in response to (i) an amount of current drawn by the component or (ii) a voltage of power received by the component. In response to detecting the fault event, the control module switches the component from the ON state to a second state, determines a first delay period according to a random process, identifies an apparent conclusion of the fault event, and in response to the apparent conclusion of the fault, waits for the first delay period before switching the component back to the ON state. The component consumes less power in the second state than in the ON state.

A cooling system is provided with a refrigerator using helium gas, a compressor that compresses the helium gas returned from the refrigerator and supplies the gas to the refrigerator, and a control unit. The control unit includes a measurement acquisition unit that acquires measurements of a plurality of different parameters representing a status of the refrigerator, or the compressor, or both, and an analysis unit that conducts multivariate analysis of the measurements acquired by the measurement acquisition unit.

The invention relates to a method for controlling a refrigeration system by establishing a defrost period during an initial defrost period. One or more compressors of the refrigeration system are monitored to establish if the one or more compressors are running, and a parameter representative of the one or more compressors running is monitored. The monitoring establishes at least one parameter limit value representative of whether a defrost period or a non-defrost period is to be initiated. The invention also relates to a method for controlling a refrigeration system subsequent to an electrical power interruption. The invention also relates to control units for applying one or both of the methods according to the invention, and to a refrigeration system having one or more control units controlling the refrigeration system according to one or both of the methods.

A superheat control utilizes a sensor at a location downstream of an evaporator after some heat is delivered to the refrigerant. In one embodiment, the compressor is a sealed compressor with at least a portion of the refrigerant being heated by an electric motor. The temperature is sensed after the refrigerant temperature has increased after passing over the electric motor. In another embodiment, the refrigerant temperature is measured after some minimal compression and minimal temperature rise has occurred within the compressor pumping elements. In either case, by measuring the temperature of the refrigerant after some additional heat has been added to the refrigerant, the refrigerant super-heat leaving the evaporator can be controlled to a lower value. The improved superheat control enhances the system performance by increasing system efficiency, system capacity and improving oil return to the compressor.