The invention relates to a non-return valve, in particular for a refrigeration or heat circuit, which valve can be inserted into a connection opening (26, 27, 28, 29) of a connection device (21) or of a pipe (39) and comprises:—a one-part or multi-part housing (42) which comprises at least one main housing (44), a feed opening (48) being provided on the inlet side and a discharge opening (51) being provided on the outlet side of the main housing (44), the feed opening and the discharge opening being interconnected by a flow channel (49);—a guide element (53) which is provided on the main housing (44) and by means of which a valve closing element (61) is guided slidably relative to the main housing (44), the valve closing element (61) being arranged in a starting position (42) by means of an energy accumulator (71) and the valve closing element (61) being slidable toward the discharge opening (51) against an actuating force of the energy accumulator (71) in order to be transferred into a working position (63), and the energy accumulator (71) being provided between the valve closing element (75) and the main housing (44), the guide element (53) of the main housing (44) having at least one through-hole (57) and at least one guide rod (59) being guided in said at least one through-hole (57), which rod at least extends from the valve closing element (61) through the at least one through-hole (57) and is secured against release from the through-hole (57), or the guide element (53) being designed as a sleeve (54) having a bottom (55), which is associated with the discharge opening (51), and the valve closing element (61) having a guide portion (66) which acts on the sleeve (54).

Refrigeration systems are described. The systems include a refrigeration circuit having a compression device, a heat rejecting heat exchanger, an expansion device, and a heat absorbing heat exchanger. The refrigeration systems include one or more sensors configured to measure a pressure associated with the heat rejecting heat exchanger, and a controller configured to compare the pressure measured by the one or more sensors to a predicted pressure, and to control the expansion device on the basis of the comparison.

Systems and methods are provided for controlling compressor systems to ensure sufficient pressure differentials to provide cooling. A compressor system includes a compressor, a suction pressure sensor at a suction of the compressor, a discharge pressure sensor, a condenser, an expansion device, a liquid line, a liquid line pressure sensor, an evaporator, a condenser blower and a controller. The method includes determining a pressure target based on an intermediate pressure within the compressor and a threshold cooling differential pressure value, determining a pressure ratio setpoint based on the pressure target and a liquid line pressure measured by the liquid line pressure sensor, controlling the condenser blower to operate based on the determined pressure ratio setpoint, determining a subcooling setpoint based on the pressure target and the liquid line pressure in the compressor system, and controlling the expansion device to operate based on the subcooling setpoint.

An expansion valve is provided with a valve body including an inlet hole through which a refrigerant flows into a valve chamber, and a valve hole through which the refrigerant flows out of the valve chamber; a valve element configured to adjust an amount of the refrigerant flowing through the valve hole; a power element that is mounted to the valve body and configured to drive the valve element via a valve rod; a first vibration isolation spring provided in the valve chamber and configured to prevent vibration of the valve element; and a second vibration isolation spring that is in contact with the valve rod and configured to prevent vibration of the valve element.

An air conditioner and a method for controlling the same are disclosed. The air conditioner implements a multistage expansion scheme by implementing serial connection between electronic expansion valves including in the R410A refrigerant-based air conditioner, and thus guarantees an optimum compression ratio in all cooling/heating load regions. Therefore, although cycle characteristics are changed by changing R410A refrigerant to R32 refrigerant, the air conditioner optimizes the cycle simply by controlling a degree of opening of electronic expansion valves, respectively. As described above, since the cycle optimization is implemented using the multistage expansion scheme in which legacy electronic expansion valves are coupled in series, the design modification is minimized without design modification of requisite constituent elements such as a heat exchanger, system implementation is facilitated, resulting in high efficiency in cost and productivity. Cooling/heating performance improvement and reliability guarantee are achieved under all load conditions, resulting in increased system efficiency.

Systems and methods are provided for controlling compressor systems to ensure sufficient pressure differentials to provide cooling. A compressor system includes a compressor, a suction pressure sensor at a suction of the compressor, a discharge pressure sensor, a condenser, an expansion device, a liquid line, a liquid line pressure sensor, an evaporator, a condenser blower and a controller. The method includes determining a pressure target based on an intermediate pressure within the compressor and a threshold cooling differential pressure value, determining a pressure ratio setpoint based on the pressure target and a liquid line pressure measured by the liquid line pressure sensor, controlling the condenser blower to operate based on the determined pressure ratio setpoint, determining a subcooling setpoint based on the pressure target and the liquid line pressure in the compressor system, and controlling the expansion device to operate based on the subcooling setpoint.

An air conditioner includes a compressor, a condenser, an expansion valve, an evaporator, and a temperature detection unit. The temperature detection unit is attached to the condenser and is configured to detect a temperature of the refrigerant in the condenser. The expansion valve is configured to be capable of adjusting a flow rate per unit time of the refrigerant flowing through the expansion valve by adjusting a degree of opening of the expansion valve. The degree of opening of the expansion valve is increased when the temperature of the refrigerant detected by the temperature detection unit rises, and the degree of opening of the expansion valve is decreased when the temperature of the refrigerant detected by the temperature detection unit falls.

A valve control device comprising a receiving unit, an opening degree control unit, and a fixing control unit. The receiving unit receives information concerning the measured temperature of a fluid to be cooled that is cooled by a vaporizer in a refrigerant circulation path that is equipped with the vaporizer and a condenser. The opening degree control unit variably controls the opening degree of a valve that controls the flow rate of the refrigerant that circulates through the circulation path in accordance with the difference between the measured temperature and a target temperature provided in advance. The fixing control unit fixes the opening degree of the valve with priority over variable control performed by the opening degree control unit in the case where a fixing condition based on the difference between the measured temperature and the target temperature and a valve opening degree variation condition is satisfied.

A bulb (5) for a thermostatic expansion valve is provided, said bulb (5) comprising a chamber (7), said chamber (7) being located within a metallic casing of said bulb and being filled with a filling adapted to influence a valve element of said thermostatic expansion valve. Service of a temperature controlled valve connected to a bulb should be facilitated. To this end said bulb (5) comprises a connection geometry (10) adapted to be connected to a capillary member (6) and said casing being provided with a closed opening zone located within said connection geometry (10), said opening zone being adapted to be opened upon mounting a counterpart (15) to said connection geometry (10).

A refrigeration system includes an evaporator within which a refrigerant absorbs heat, a gas cooler/condenser within which the refrigerant rejects heat, a compressor operable to circulate the refrigerant between the evaporator and the gas cooler/condenser, a high pressure valve operable to control a pressure of the refrigerant at an outlet of the gas cooler/condenser, and a controller. The controller is configured to automatically generate a setpoint for a measured or calculated variable of the refrigeration system based on a measured temperature of the refrigerant at the outlet of the gas cooler/condenser. The setpoint is generated using a stored relationship between the measured temperature and a maximum estimated coefficient of performance (COP) that can be achieved at the measured temperature. The controller is configured to operate the high pressure valve to drive the measured or calculated variable toward the setpoint.