An air conditioning system that includes at least one indoor unit that uses water as a working fluid, an outdoor unit that uses a refrigerant as a working fluid, the outdoor unit including a compressor compressing the refrigerant and an outdoor heat exchanger for heat-exchange with the refrigerant, and a heat collection unit connecting the at least one indoor unit to the outdoor unit, the heat collection unit including at least one heat exchange part for heat-exchanging water supplied from the at least one indoor unit with the refrigerant supplied from the outdoor unit.

A vehicle heat exchanger is disclosed that includes a heat exchange unit having first and second plates layered to alternately form a first and second flow path. Operation fluids passing through the paths exchange heat. A first inflow aperture is formed on a second surface of the unit and connected to the first flow path. A first exhaust aperture is formed corresponding to the first inflow aperture on the first surface of the unit and connected to the first flow path. A connection aperture is formed in the plates, connected to the first flow path, and closing a connection to the second flow path. A second inflow aperture is formed corresponding to the first inflow aperture and connected to the second flow path. A second exhaust aperture is formed at a center of the unit and connected to the second inflow aperture through the second flow path.

A heat pump apparatus includes a heat source-side refrigeration cycle sequentially connecting a compressor, a heat source-side heat exchanger, an expansion valve, and a heat source side of a cascade heat exchanger, and configured to circulate refrigerant, and a load-side refrigeration cycle sequentially connecting a heat medium sending unit, a load-side heat exchanger, and a load side of the cascade heat exchanger, and configured to circulate a heat medium. The heat source-side heat exchanger and the cascade heat exchanger each have a hydraulic diameter of less than 1 mm, which is calculated by 4S/L, where S represents a cross-sectional area of a fluid passage and L represents a length of a wetted perimeter.

An apparatus using a heat pump includes a refrigerant circuit and a heat medium circuit. The refrigerant circuit is capable of performing a first operation, in which a load-side heat exchanger is used as a condenser, and a second operation, in which the load-side heat exchanger is used as an evaporator. A main circuit of the heat medium circuit has a branching part and a joining part. An overpressure protection device and a refrigerant leakage detecting device are connected to the main circuit. The overpressure protection device is connected to a connection part that is located between the load-side heat exchanger and one of the branching part and the joining part, or at the load-side heat exchanger. The refrigerant leakage detecting device is connected to the other of the branching part and the joining part, between the connection part and the other of the branching part and the joining part, or at the connection part. When leakage of refrigerant into the heat medium circuit is detected, the state of a refrigerant flow switching device is set to a second state, an expansion device is set to a closed state, and a compressor is operated.

A double acting alpha Stirling refrigerator includes a piston cylinder and a piston, the piston is provided in the piston cylinder. The piston is in a clearance fit with an inner wall of the piston cylinder. A closed cavity is formed inside the piston. A cross-shaped four-way pipe is provided in the cavity of the piston. A one-way air outlet valve and a one-way air inlet valve are further respectively provided on the four-way pipe in the cavity of the piston. An air outlet for connecting the cavity of the piston to the inner cavity of the piston cylinder is provided on the piston. A traction frame movable relative to the piston cylinder is provided outside the piston cylinder, and the movement of the piston is controlled by the movement of the traction frame.

An air-conditioning apparatus includes a refrigerant circuit in which a compressor, a heat source heat exchanger, an expansion device, and a load heat exchanger are connected via refrigerant pipes; a refrigerant leakage sensor configured to output a refrigerant leakage detection signal indicating detection of refrigerant leakage when the refrigerant leakage sensor detects the refrigerant leakage; a refrigerant leakage cutoff device configured to cut off a flow of refrigerant when the refrigerant leakage cutoff device is set to a closed state; and a controller configured to determine whether refrigerant leakage occurs on the basis of an operating state and whether the refrigerant leakage detection signal is received from the refrigerant leakage sensor. When the controller receives the refrigerant leakage detection signal and determines, on the basis of the operating state, that the refrigerant leakage occurs, the controller is configured to set the refrigerant leakage cutoff device to the closed state.

The invention provides a filtration system with a rotating core driving thimble opening and closing water passage, comprising a casing, a filter and a connector, wherein the filter and the connector are connected and fixed in an inner cavity of the casing, the casing consists of an upper cover of the casing and a lower cover of the casing, which are connected via a connecting member; a connector core of the present invention has a groove and a boss thereon, the connector core, a water intake thimble and a water outtake thimble are tightly pressed by a spring, when the connector is rotated, the water intake thimble and the water outtake thimbles are raised from the position of the groove to the position of the boss, and the water passage is opened. When disassembled, the connector is lowered from the position of the boss to the position of the groove, and the water passage is closed, preventing the leakage of the connector water due to the removal of a filter element. Due to the action of the spring, even if the water intake thimble and the water outtake thimble are worn seriously, the water intake sealing ring and the water outtake thimble sealing ring is attached to a water intake thimble sleeve and a water outtake thimble sleeve, realizing the sealing and not causing the leakage phenomenon.

A device for preventing refrigerant leaks in air conditioning system service ports includes a quick coupler for engaging the service port. A main body is disposed adjacent the coupler. A stem is movable inside the main body and a first sealing element is adjacent the stem. A head which is fastened to the main body has an internal thread and a second sealing element is disposed within the head. A shaft has an external thread to be screwed into the internal thread of the head. The shaft has an end with a recess to be engaged by a tool and the shaft has a free end remote from the recess for contacting the second sealing element, for pushing the second sealing element against the stem and for pushing the first sealing element adjacent the stem against an end of the service port upon turning the shaft.

A method of shutting down a refrigeration system including: initiating a shutdown process of the refrigeration system; closing a first valve within a refrigerant circuit of the refrigeration system; operating a compressor within the refrigerant circuit; detecting a suction pressure within the refrigerant circuit; closing a second valve within the refrigerant circuit of the refrigeration system when the suction pressure is below a threshold suction pressure; and stopping operation of the compressor.

Provided is a refrigeration apparatus with improved safety. A refrigeration apparatus includes: a compressor; a heat source-side expansion valve to be controlled to have a minimum opening degree and brought into a closed state in which the heat source-side expansion valve maximizes prevention of a flow of a refrigerant toward a usage-side refrigerant circuit; a fusible plug; a controller; and a refrigerant leak detector configured to detect a refrigerant leak at the usage-side refrigerant circuit. The fusible plug is disposed in a refrigerant circuit, and is brought into an open state to allow the refrigerant circuit to communicate with an external space. When the refrigerant leak detector detects a refrigerant leak at the usage-side refrigerant circuit, the controller performs refrigerant leak first control to bring the heat source-side expansion valve into the closed state, and performs refrigerant leak second control to bring the fusible plug into the open state.