A system for starting a refrigeration system includes a liquid line regulating valve, a liquid line charging valve, a suction line expansion valve, a suction line charging valve, and a controller. The controller is configured to override normal operation of the refrigeration system and transmit a demand signal to enable partial system operation. The controller is configured to operate the liquid line regulating valve and the liquid line charging valve to charge a receiver tank, gradually increase the demand signal to a predetermined level of partial system operation, and release the liquid line charging valve to normal operation. The controller is configured to operate the suction line expansion valve and the suction line charging valve to charge a suction line, gradually increase the demand signal to full system operation, and release the liquid line regulating valve, the suction line expansion valve, and the suction line charging valve to normal operation.

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.

There are provided a heat exchange apparatus and an air conditioner in which an occurrence of uneven refrigerant distribution of a heat exchanger is reduced such that heat exchange performance improves. The heat exchange apparatus includes: a heat-transfer pipe through which a refrigerant flows; a heat exchanger in which a plurality of the heat-transfer pipes are connected to one another; a distributor that distributes the refrigerant to the plurality of heat-transfer pipes; an inflow pipe that causes the refrigerant to flow into the distributor; and a confluent pipe which is connected to an intermediate position of the inflow pipe and in which the refrigerant flowing through an inside thereof is to merge with the refrigerant flowing through an inside of the inflow pipe. A merging part between the inflow pipe and the confluent pipe is positioned in the vicinity of the distributor.

Disclosed is an air conditioner and control method thereof. The air conditioner and control method thereof is to improve rapid heating performance without using a large-capacity compressor. The air conditioner includes an indoor unit having a first heat exchanger, an outdoor unit having a compressor and a second heat exchanger, a refrigerant cycle configured to form a refrigerant circulation path between the indoor unit and the outdoor unit, a flow path switch configured to switch a flow of a refrigerant in the refrigerant cycle, and a controller configured to control the flow path switch to allow one part of the refrigerant discharged from the compressor to flow into an inlet of the compressor and the other part of the refrigerant discharged from the compressor to flow into at least one of the first heat exchanger and the second heat exchanger.

A split-type air conditioning and heat pump system an indoor unit, an outdoor unit and an energy efficient arrangement. The indoor unit includes an indoor housing having an indoor air inlet, and an indoor heat exchanger. The outdoor unit includes an outdoor housing, a compressor, an outdoor heat exchanger and a fan unit. The energy efficient arrangement includes an energy saving heat exchanger supported in the indoor housing and connected to the indoor heat exchanger and the outdoor heat exchanger. The energy saving heat exchanger is positioned between the indoor air inlet and the indoor heat exchanger so that air from an indoor space is arranged to pass through the energy saving heat exchanger before reaching the indoor heat exchanger.

A control valve includes a shaft, a stopper mechanism, and a can. A stator coil is coaxially mounted around the can. Positions in a rotating direction of the rotor and the stator when the shaft is stopped by an operation of the stopper mechanism are set to be reference positions at which magnetic poles of the stator and those of the rotor are opposite to each other. The rotor is configured to be stopped at the reference position by an arrangement of the stopper mechanism. The stator coil is positioned relative to the body according to a positional relation between a fitting part formed on surfaces of the stator and the body attached to each other and an insertion part where the can is inserted into the stator, and magnetic poles of the stator and those of the rotor are made opposite to each other at the reference positions.

The invention relates to an electromagnetically actuatable expansion valve for a refrigerant, said valve comprising a valve body (1) with a bore (2), in which a substantially cylindrical valve slide (3) is arranged such that it can be displaced axially in order to connect a supply line (4) to a discharge line (5). According to the invention, the discharge line (5) is formed by a hollow cylinder (6) which is inserted in the bore (2) and the end of which facing the valve slide (3) forms a valve seat (7) that can be closed by means of a separate valve closure element (8).

Provided is an expansion valve, including: a case having a valve chamber formed therein; and a valve element arranged in the valve chamber. The case includes: a side wall portion to which a first pipe is connected; and an end wall portion to which a second pipe is connected. The end wall portion has a fluid communication hole to be opened and closed by the valve element. The fluid communication hole is formed so that the following expression is satisfied: L<λ/2, where L represents an axial length of the fluid communication hole, and λ represents a resonance wavelength.

A vapor compression system comprises a compressor, a condenser, an expansion device, e.g. in the form of an expansions valve, and an evaporator arranged along a refrigerant path. A method for operating the vapor compression system comprises the steps of: obtaining a superheat value being representative for the superheat of refrigerant entering the compressor; obtaining a subcooling value being representative for the subcooling of refrigerant entering the expansion device; and operating the expansion device on the basis of the obtained superheat value and on the basis of the obtained subcooling value. The subcooling value is taken into account when operating the expansion device, because variations in the subcooling value have significant influence on the refrigerating capacity of the evaporator at a given opening degree of the expansion device, thereby resulting in a more stable operation of the system. The system may further comprise an internal heat exchanger.

A method of operating an electronic expansion valve of a heating, ventilation, air conditioning and refrigeration system includes detecting superheat of an evaporator of the heating, ventilation, air conditioning and refrigeration system and calculating a derivative of evaporator superheat with respect to time. The derivative of evaporator superheat with respect to time is compared to a selected derivative range, and the electronic expansion valve is closed at a rapid closure step increment higher than a normal closure step increment if the derivative is within the selected derivative range.