F25B2500/26

A METHOD FOR CONTROLLING A SUPPLY OF REFRIGERANT TO AN EVAPORATOR INCLUDING CALCULATING A REFERENCE TEMPERATURE
20170328617 · 2017-11-16 ·

A method for controlling a supply of refrigerant to an evaporator (2) of a vapour compression system (1) is disclosed. During a system identification phase an opening degree (12) of the expansion valve (3) is alternatingly increased and decreased, and a maximum temperature difference, (S.sub.4−S.sub.2).sub.max, between temperature, S.sub.4, of air flowing away from the evaporator (2) and temperature, S.sub.2, of refrigerant leaving the evaporator (2) is determined. During normal operation, the supply of refrigerant to the evaporator (2) is controlled by calculating a reference temperature, S.sub.2,ref, based on the monitored temperature, S.sub.4, and the maximum temperature difference, (S.sub.4−S.sub.2).sub.max, determined during the system identification phase. The supply of refrigerant to the evaporator (2) is controlled in order to obtain a temperature, S.sub.2, of refrigerant leaving the evaporator (2) which is substantially equal to the calculated reference temperature, S.sub.2,ref.

System for deicing an external evaporator for heat pump systems
11262114 · 2022-03-01 · ·

A system for deicing an external evaporator for heat pump systems includes at least one compressor, at least one internal condenser, at least one external evaporator, at least one liquid separator, and a system of ducts for cooling fluid. The deicing system includes a secondary refrigeration circuit, which includes a tank for storing a heat transfer fluid, and a first heat exchanger immersed in the heat transfer fluid and adapted to transfer heat to the heat transfer fluid by cooling the cooling fluid. The system further includes a bypass refrigeration circuit, which includes the tank, and a second heat exchanger immersed in the heat transfer fluid and adapted to absorb heat from the heat transfer fluid by heating the cooling fluid. The system also includes a deicing circuit adapted to convey cooling fluid.

METHOD OF OPERATING AN ELECTRONIC EXPANSION VALVE IN AN AIR CONDITIONER UNIT
20230167998 · 2023-06-01 ·

An air conditioner unit includes a refrigeration loop including an indoor heat exchanger and an outdoor heat exchanger, a compressor for circulating refrigerant, and an electronic expansion valve. A controller receives a command to perform an operating cycle at a target compressor speed, determines a starting position of the electronic expansion valve using a valve position equation that is a function of the target compressor speed, an indoor temperature, an outdoor temperature, and empirically determined constants, and initializes the operating cycle with the electronic expansion valve at the starting position.

REFRIGERATION SYSTEM HAVING A VARIABLE SPEED COMPRESSOR
20170314821 · 2017-11-02 ·

A two-stage cascade refrigeration system is provided having a first refrigeration stage and a second refrigeration stage. The first refrigeration stage defines a first fluid circuit for circulating a first refrigerant, and has a first compressor, a condenser, and a first expansion device. The second refrigeration stage defines a second fluid circuit for circulating a second refrigerant, with the second refrigeration stage having a second compressor that is a variable speed compressor, a second expansion device, and an evaporator. A heat exchanger is in fluid communication with the first and second fluid circuits to exchange heat between the first and second refrigerants. A controller stages operation of the first and second compressors and runs the second compressor at an initial speed less than a maximum speed initially when a staging protocol is performed during start up or re-starting of the refrigeration system.

SUPERCRITICAL TRANSIENT STORAGE OF REFRIGERANT
20170314830 · 2017-11-02 ·

A refrigeration system is described that includes a compression device configured to increase a pressure of a refrigerant. The refrigeration system further includes a first heat exchanger configured to reject heat from the refrigerant and reduce a temperature of the refrigerant. The refrigeration system further includes a storage device configured to store the refrigerant at a supercritical state. The refrigeration system further includes an expansion device configured to reduce the pressure of the refrigerant. The refrigeration system further includes a second heat exchanger configured to absorb heat into the refrigerant and increase the temperature of the refrigerant. The refrigeration system further includes a controller configured to release the refrigerant from the storage device to the expansion device to provide cooling capacity to the refrigeration system.

Air-conditioning apparatus with regulation of injection flow rate

An air-conditioning apparatus includes a suction-injection pipe that introduces a refrigerant in a liquid or two-phase state into a suction side of a compressor, an expansion device that is arranged at the suction-injection pipe, and a controller that regulates the suction-injection flow rate of a refrigerant introduced into the suction side of the compressor through the suction-injection pipe by controlling the opening degree of the expansion device.

Intermittent start compressor
09796248 · 2017-10-24 · ·

A switch (10, 200) is provided for installation in the air conditioning (A/C) system (12) in a vehicle (16) for intermittently operating the clutch (20) in the A/C system (12) each time the control (44) in the A/C system (12) provides power to operate the clutch (20) to prevent slugging. This turns the compressor (14) a few turns each time the clutch (20) is energized during intermittent operation to purge liquid refrigerant and lubricant from the compressor (14) to prevent slugging. The switch (10, 200) can be installed in existing vehicles by connecting the switch (10, 200) in the wiring harness (18) of the A/C system (12) to the power lead (38) from the control (44) to the clutch (20) and between the ground lead (40) from the clutch (20) and a ground. The switch (10, 200) can include a microcontroller (52) for controlling the operation of a power transistor (70) to intermittently ground the clutch to provide the intermittent operation. A battery (202) can be provided to power the microcontroller (52) for a set period of time after an initial intermittent operation. This prevents additional intermittent operation for the set period of time.

Refrigerator

In a refrigerator including a sliding door configured to open and close a storage chamber, a storage basket provided on a rear portion of the sliding door, and a support frame configured to support the sliding door and the storage basket, sidewalls of the storage basket may be formed so as to protrude outwardly except a lower portion in which the support frame is disposed between an inner case and the sidewalls, thereby increasing a storage space of the storage basket. In addition, a front protrusion, an auxiliary protrusion, and a rear protrusion are formed in an upper portion of the storage basket, and therefore a relative position of an auxiliary basket to the storage basket may be limited, and the auxiliary basket may be drawn into and out in conjunction with drawn-in and -out movements of the storage basket.

MICROCHANNEL EVAPORATORS WITH REDUCED PRESSURE DROP
20170299239 · 2017-10-19 ·

In one general aspect, a converging split-flow microchannel evaporator is disclosed. It includes a conductive contact surface to mate to a surface to be cooled, with a core mounted in thermal connection with the conductive surface that defines at least one layer of microchannels. Within the core, one inlet restriction restricts the flow into each microchannel in a first group of the microchannels, and another restricts the flow into each microchannel in a second group. A centrally located fluid outlet receives the flows from opposite ends of the microchannels in the two groups. A check valve can be provided to help ensure ready startup without reverse flow.

Intelligent compressor flooded start management
09791175 · 2017-10-17 · ·

A method is provided for managing a flooded start of a compressor in a vapor compression system. Following an initial bump start, a determination is made as to whether working fluid in a liquid state remains in the sump of the compressor. If working fluid in a liquid state remains in the compressor sump, an additional bump start of the compressor is completed, followed by another determination as to whether working fluid in a liquid state still remains in the compressor sump. If working fluid in a liquid state remains in the compressor sump, another bump start of the compressor is initiated and the sequence repeated until no working fluid in the liquid state remains in the compressor sump. A normal start of the compressor may be initiated after determining no working fluid in the liquid state remains in the compressor sump.