Abstract: A heat source unit of a refrigerant cycle apparatus includes a compressor, a pipe, and a fixing member. The compressor includes two or three connection portions of a first connection portion connecting a suction pipe, a second connection portion connecting a discharge pipe, and a third connection portion connecting an injection pipe. The pipe includes a vertical portion. At least a part of the vertical portion extends vertically from each of the two or three connection portions. The fixing member fixes at least two of the vertical portions of two or three of the pipes of the suction pipe, the discharge pipe, and the injection pipe. Each of the connection portions of the pipes fixed by the fixing member is located on a first straight line as seen in a top view.

Abstract: The refrigerant circuit includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, and a second flow path switching unit. The outdoor heat exchanger has a plurality of first flat heat transfer tubes, a plurality of second flat heat transfer tubes, and a plurality of third flat heat transfer tubes. The second flow path switching unit switches the refrigeration cycle apparatus between a third state and a fourth state. In the third state, the plurality of first flat heat transfer tubes and the plurality of third flat heat transfer tubes are sequentially connected in series. In the fourth state, the plurality of first flat heat transfer tubes, the plurality of second flat heat transfer tubes, and the plurality of third flat heat transfer tubes are connected in parallel to each other.

Abstract: A system includes a first set of coils receive coolant from a first coolant line and provide the coolant to a second coolant line. A second set of coils receive coolant from a third coolant line and provide the coolant to a fourth coolant line. A first valve regulates flow of coolant between the first and third coolant line. A second valve regulates flow of coolant between the second and the fourth coolant lines. A third valve regulates flow of coolant between the fourth coolant line and a fifth coolant line coupled to a water evaporator and a three-way valve. The three-way valve regulates flow of coolant between the fifth coolant line, the third coolant line, and a coolant input line. A fourth valve regulates flow of coolant between the second coolant line and a water condenser. A controller adjusts the valves to operate in an intermediate temperature mode.

Abstract: The present disclosure relates to a heat exchanger and an air conditioner including the same. The heat exchanger may be provided for heat exchange between refrigerant and air. The heat exchanger may include a plurality of refrigerant tubes that are disposed with a clearance (C) therebetween in a first direction (A), in which the air moves, and are disposed to be spaced apart in a second direction (B) crossing the first direction (A) and a plurality of heat exchange fins that are disposed between the plurality of refrigerant tubes disposed to be spaced apart in the second direction (B).

Abstract: The present invention provides a liquid level sensor and an automatic calibration process which removes the need for prior manual calibration of the liquid level sensor, as this happens dynamically during installation and use of the pump. Further, by frequently monitoring the calibration of the sensor and correcting for long term drift or contamination on the sensing surface, the reliability of the liquid level sensor is considerably better than those of the prior art. By operating a solid state sensor, there are no moving parts in the liquid level sensor described above.

Abstract: A refrigeration apparatus (1) includes a heat-source-side unit (10) using a refrigerant that works in a supercritical region. The heat-source-side unit (10) includes a compression element (20) configured to compress the refrigerant, a heat-source-side heat exchanger (24), an expansion valve (26) provided downstream of the heat-source-side heat exchanger (24), a receiver (25) provided downstream of the expansion valve (26), and a control unit (101). The control unit (101) performs a first operation for evaluating the amount of the refrigerant based on a high-pressure-side pressure, on a first condition that the internal pressure of the receiver (25) be equal to or less than a supercritical pressure.

Abstract: A temperature control system is used for controlling a temperature of a control target. The system includes: a first circulation circuit through which a first heat transfer medium circulates; a second circulation circuit that is independent of the first circulation circuit and through which a second heat transfer medium circulates; and a third circulation circuit that is independent of the first circulation circuit and the second circulation circuit and through which a third heat transfer medium circulates. The third heat transfer medium has a usable temperature range wider than usable temperature ranges of the first heat transfer medium and the second heat transfer medium.

Abstract: Refrigeration management includes determining an optimal operational schedule to control a refrigeration system for a cold storage facility. Various approaches can be used to determine an operational schedule with an optimal operational outcome that satisfies constraints representative of a range of factors, such as thermal characteristics of a refrigeration management system, energy cost, and environmental factors external to the system, which can affect refrigeration management of a cold storage facility.

Abstract: The disclosed technology includes an on-demand water heater which uses a heat pump to heat the fluid. The on-demand heat pump water heater can have a low fluid capacity heating chamber which has an inlet and an outlet, a heat pump for heating the fluid, and a controller to control the heat pump and maintain the temperature of the fluid at a predetermined temperature. The on-demand heat pump water heater can include one or more temperature sensors, flow sensors, fluid mixing valves, or supplemental heat sources.

Abstract: A refrigeration system is provided. The refrigeration system includes: an indoor heat exchange module configured for refrigerant to absorb heat; outdoor heat exchange modules for the refrigerant to dissipate heat. The outdoor heat exchange module includes a compression device and a condensing device; the outdoor heat exchange module is switchable between an active mode and a standby mode; in the active mode, the outdoor heat exchange module is connected to the indoor heat exchange module; in the standby mode, the outdoor heat exchange module is disconnected from the indoor heat exchange module, and the compression device of the outdoor heat exchange module is in an operation status.

Abstract: The auxiliary AC system includes a temperature measurement device configured to generate a variable output based on an air temperature in an environment proximate to the AC system and a compressor control circuit communicably coupled to a variable speed motor. The compressor control circuit is configured to receive the variable output from the temperature measurement device, determine that the output indicates a change in the air temperature, and generate a control signal for the variable speed motor, the control signal including a current having a magnitude depending on the extent of the change to vary a rate at which a compressor pressurizes a refrigerant vapor.

Abstract: Example embodiments of the present disclosure relate to a heat pump assembly including a system or method for detecting a fault in the heat pump. Some embodiments include a method for detecting a switch over valve fault where the heat pump includes a refrigerant cycle, a compressor, a metering device, a first heat exchanger, an second heat exchanger, a temperature sensor, and a switch over valve, and where the method includes operating the HVAC system in one either a heating mode or a cooling mode, monitoring a refrigerant temperature associated with the refrigerant cycle using the temperature sensor, monitoring an outdoor ambient air temperature, determining a temperature difference between the refrigerant temperature and the outdoor ambient temperature, determining whether the temperature difference is greater than a predetermined temperature difference threshold, and declaring a switch over valve fault when the temperature difference is greater than the predetermined temperature difference threshold.

Abstract: A method of initiating a low-energy cooling mode using a controller of an HVAC system includes measuring a temperature of ambient air proximal to a condenser coil and determining whether the temperature of the ambient air proximal the condenser coil is less than a temperature threshold. If the temperature of the ambient air is less than the temperature threshold, the HVAC system is configured to operate in a low-energy cooling mode. In the low-energy cooling mode, the controller opens a first bypass valve to allow a refrigerant to bypass a compressor and the compressor is powered off. The HVAC system is operated until a cooling demand has been met.

Abstract: A surface cooler configured to be operably coupled to an aircraft fan casing includes a body having a first surface configured to confront the aircraft fan casing and a second surface opposite the first surface, multiple fluid passages located within the body, and a set of fins located on at least the second surface of the body.

Abstract: Double hybrid heat pumps, systems, and methods of operation that provide increased efficiency in both heating and cooling modes, heated water, and other advantages. The system includes a compressor for compressing low-pressure vapor phase refrigerant to high-pressure vapor phase refrigerant, a refrigerant condensing heat exchanger to heat water and cool the refrigerant to a high-pressure liquid refrigerant, which is provided to a refrigerant cooling heat exchanger in which any remaining high-pressure vapor phase refrigerant is condensed and the high-pressure liquid refrigerant is further cooled. The high-pressure cooled liquid refrigerant is passed through an expansion valve to drop the pressure of the cooled liquid to yield a low-pressure cooled liquid refrigerant or low-pressure cooled two-phase refrigerant. The low-pressure cooled liquid or two-phase refrigerant is then evaporated in a refrigerant evaporating heat exchanger to produce the low-pressure vapor refrigerant that is returned to the compressor.

Abstract: A thermal management system that includes an open-circuit refrigeration system having an open-circuit refrigerant fluid flow path is described. The open-circuit refrigeration system includes a receiver configured to store a refrigerant fluid, an evaporator configured to receive the refrigerant fluid at a evaporator inlet and to extract heat from a heat load that contacts the evaporator, and provide refrigerant vapor at a evaporator outlet. The open-circuit refrigeration system also includes a vapor pump device having a vapor pump inlet that receives the refrigerant vapor and having a vapor pump outlet that outputs compressed refrigerant vapor to an exhaust line coupled to the vapor pump outlet, with the receiver, the evaporator, the vapor pump device, and the exhaust line connected in the open-circuit refrigerant fluid flow path.

Abstract: Embodiments include heat pump systems with gas bypasses and related methods. In one embodiment, a system may include a gas bypass tank having a bypass inlet, a liquid outlet, and a vapor outlet, and a first splitting valve having a first splitter outlet in fluid communication with the bypass inlet, a first splitter inlet in fluid communication with the liquid outlet, and a first switching path configured to switch between a first conduit path in fluid communication with a first coil system and a second conduit path in fluid communication with a second coil system.

Abstract: A multi-air conditioner for heating/cooling operations, including at least one indoor unit for heating/cooling operations including an indoor heat exchanger; and an outdoor unit for heating/cooling operations including a compressor, an outdoor heat exchanger, and a switching unit configured to be disposed in a discharge side of the compressor to switch a flow of refrigerant. The outdoor unit includes a receiver that selectively stores refrigerant or oil according to a cooling or heating operation mode and provides the stored refrigerant or oil to the compressor. Accordingly, in the accumulator of the multi-air conditioner using the receiver, the receiver which is not used in the heating mode may be converted and used for oil storage, thereby preventing oil burnout without adding structure.

Abstract: An air conditioning system, which includes an indoor heat exchanger, an outdoor heat exchanger, a compressor, a throttling device, a four-way valve and an ejection device; the indoor heat exchanger, the outdoor heat exchanger, the compressor and the throttling device form a closed-loop refrigerant circulation circuit, the four-way valve is configured to switch the air conditioning system between a cooling mode and a heating mode, and the ejection device is configured to be capable of being connected to a discharge side of the compressor when the air conditioning system executes the heating mode, so as to improve a heating effect of the air conditioning system. This system has a lower cost and a simple structure for easier maintenance, and the energy efficiency ratio is improved, so that the heating effect of the air conditioning system can be improved when the air conditioning system executes the heating mode.

Abstract: A method of mitigating liquid-refrigerant migration includes comparing a requested compressor speed of a variable-speed compressor to a pre-defined threshold and, responsive to a determination that the requested compressor speed is greater than the pre-defined threshold, operating the variable-speed compressor at a first compressor speed that is less than the requested compressor speed.