A heat source controller performs a first operation when a compression element is in a stopped state and a pressure in a receiver exceeds a predetermined first pressure. The heat source controller allows an inlet of the compression element to communicate with the receiver, and drives the compression element in the first operation.

An energy efficient heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a vapor compression circuit, a heat exchanger of the vapor compression circuit configured to place a working fluid in a heat exchange relationship with an air flow directed across the heat exchanger, and a conduit system of the vapor compression circuit. The conduit system of the vapor compression circuit is configured to direct the working fluid into the heat exchanger and to receive the working fluid from the heat exchanger, wherein the conduit system is configured to direct the working fluid into the heat exchanger to place the working fluid in a counterflow arrangement with the air flow directed across the heat exchanger in a cooling mode of the heat pump and in a heating mode of the heat pump.

A brazed plate heat exchanger (100) includes a plurality of first and second heat exchanger plates (110, 120) having different patterns of ridges and grooves providing contact points between neighbouring plates under formation of interplate flow channels for fluids to exchange heat, said interplate flow channels being in selective fluid communication with first, second, third and fourth large port openings (O1, O2, O3, O4) and first and second small port openings (SO1, SO2) forming a suction gas heat exchanger together with a dividing surface (DW). The ridges (R1, R2a, R2b) and grooves (G1, G2a, G2b) are formed such that the interplate flow channels between different plate pairs have different volumes. Disclosed is also a refrigeration system and method including such as heat exchanger.

Methods and related systems for controlling superheat in a climate control system are disclosed. In an embodiment, the method includes (a) determining a superheat of a refrigerant downstream of a coil of a heat exchanger of the climate control system. In addition, the method includes (b) determining that an expansion valve upstream of the heat exchanger is fully open. Further, the method includes (c) adjusting a speed of air flowing across the coil or a speed of a compressor of the climate control system after (b) based on the determination in (a) to control the superheat of the refrigerant.

The present invention provides a system and method for an improved multistage, cascade refrigeration system using hot gas defrost to rid the evaporator of ice build-up which accumulates over time, while the air in the evaporator enclosure remains below the freezing point of water. The present invention thus provides greater defrost flexibility with increased ease of design and implementation than current refrigeration systems, which allows for more robust hot gas defrost function for multistage refrigeration systems, such that it is unaffected by temperature changes of the condensing fluid (ambient air temperature for air cooled condensers, water temperature for water cooled condensers), and can be readily adapted to any refrigerant suitable for a selected temperature range.

A solenoid valve with a hard seal structure includes a valve body having a fluid passage and an accommodating cavity, and a valve assembly mounted inside the accommodating cavity. The valve assembly includes a fluid inlet seat, a valve core cooperating with the fluid inlet seat, and a driving mechanism for driving reciprocating motion of the valve core. The fluid inlet seat has a guide hole that allows the value core to stretch therein, a middle section of the fluid inlet seat has fluid inlet holes, and a lower section of the fluid inlet seat has a valve core fluid passage and a fluid passage slant located at the valve core fluid passage. The valve core includes a bigger-diameter section, a slant section, a smaller-diameter section and a valve core end slant sequentially arranged from up to down.

An air conditioner including an outdoor unit having a compressor, an outdoor heat exchanger, a main expansion device, and a refrigerant pipe configured to connect the outdoor heat exchanger to the main expansion device; an indoor unit having an indoor heat exchanger; and a connection pipe configured to connect the outdoor unit to the indoor unit, wherein the air conditioner has refrigeration capacity of 2 kW to 7 kW, a R134a is used as the refrigerant, the refrigerant pipe is made of a ductile stainless steel material having a delta ferrite matrix structure of 1% or less on the basis of a grain area, and the refrigerant pipe includes a suction pipe that guides suction of a refrigerant into the compressor and has an outer diameter of 12.70 mm.

A refrigeration cycle apparatus includes an outdoor unit including a compressor, a first heat exchanger, and a first expansion valve, an indoor unit including a second expansion valve and a second heat exchanger, and a first pipe and a second pipe connected between the outdoor unit and the indoor unit. In a cooling operation, refrigerant delivered from the compressor sequentially passes through the first heat exchanger, the first expansion valve, the first pipe, the second expansion valve, the second heat exchanger, and the second pipe and returns to the compressor, and in the cooling operation, the first expansion valve converts refrigerant from a liquid-phase state to a two-phase state and sends two-phase refrigerant to the first pipe.

A multi-type air conditioner is provided including an outdoor unit and a plurality of indoor units connected to the outdoor unit by a liquid pipe and a gas pipe. The plurality of indoor units includes a first indoor unit including first and second heat exchangers and first and second heat exchanger connecting pipes, and a second indoor unit. An indoor heat exchanger connecting pipe connects the first and second indoor units, and a liquid pipe connecting tube connects the first indoor unit and the liquid pipe. Opening amounts of a first indoor expansion valve, and first and second bypass expansion valves provided in the first indoor unit are opened selectively to operate the first heat exchanger as a condenser and the second heat exchanger as an evaporator to continuously drive a dehumidification mode while maintaining a room temperature within a predefined range.

A solenoid valve with a hard seal structure includes a valve body having a fluid passage and an accommodating cavity, and a valve assembly mounted inside the accommodating cavity. The valve assembly includes a fluid inlet seat, a valve core cooperating with the fluid inlet seat, and a driving mechanism for driving reciprocating motion of the valve core. The fluid inlet seat has a guide hole that allows the value core to stretch therein, a middle section of the fluid inlet seat of fluid inlet holes, and a lower section of the fluid inlet seat has a valve core fluid passage and a fluid passage slant located at the valve core fluid passage. The valve core includes a bigger-diameter section, a slant section, a smaller-diameter section and a valve core end slant sequentially arranged from up to down.