A refrigerant cycle apparatus is configured to suppress extension of defrost time. The refrigerant cycle apparatus includes: a refrigerant circuit; a first temperature sensor configured to measure first refrigerant temperature between the main heat exchange unit and the pressure loss portion; a second temperature sensor configured to measure second refrigerant temperature between the pressure loss portion and the expansion mechanism; and a controller configured to control the flow direction switching mechanism to switch between normal operation and defrost operation. The controller has control modes for the defrost operation, including a control mode of terminating the defrost operation based on the first refrigerant temperature and a control mode of terminating the defrost operation based on the second refrigerant temperature.

The present disclosure provides an air conditioner defrosting control method and device, and a storage medium and an air conditioner. The control method includes: setting a target discharge temperature of a compressor and an initial opening degree of a throttle device when an air conditioner performs defrosting according to an outdoor ambient temperature when the air conditioner meets a defrosting condition and enters a defrosting mode; controlling a defrosting operation of the air conditioner according to the target discharge temperature of the compressor and the initial opening degree of the throttle device; and controlling the air conditioner to exit the defrosting mode when a temperature of an outdoor heart exchanger of the air conditioner reaches a set temperature value.

A water regulator includes a water regulation valve, a first temperature sensor, a second temperature sensor, and a controller. The water regulation valve regulates a quantity of water flowing through water pipes. The first temperature sensor measures a temperature of one of the water pipes which is connected to an inlet of a heat exchanger. The second temperature sensor measures a temperature of one of the water pipes which is connected to an outlet of the heat exchanger. The controller controls an opening degree of the water regulation valve, based on a difference between the temperature measured by the first temperature sensor and the temperature measured by the second temperature sensor.

A transport refrigeration system includes a compressor, a heat rejection heat exchanger, a flash tank, an expansion device and a heat absorption heat exchanger arranged in a serial refrigerant flow order to circulate a refrigerant; a controller configured to: determine a presence of at least one condition of the transport refrigeration system; and initiate a low refrigerant charge detection process in response to detecting the presence of the at least one condition of the transport refrigeration system.

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.

The present disclosure relates to a multi-circuit heating, ventilation, and air conditioning (“HVAC”) system for use with a first refrigerant in a first refrigerant circuit and a second refrigerant in a second refrigerant circuit. The second refrigerant circuit is fluidically isolated from the first refrigerant circuit. Additionally, a first sensor is operable to detect a leak of at least one of the first and second refrigerants or is operable to measure temperature or pressure from the first refrigerant circuit or the second refrigerant. The multi-circuit HVAC system further including a controller programmed to receive the measurement from the sensor to identify the circuit or circuits that are leaking, to turn off operation of the leaking circuit or circuits, and if only one circuit is leaking, operate only the other of the circuits.

Provided is a multi-type air conditioner, including: an outdoor unit comprising a liquid pipe through which liquid refrigerant flows and a gas pipe through which gas refrigerant flows; a plurality of indoor units comprising a first indoor unit and a second indoor unit each connected to the liquid and gas pipelines to circulate a refrigerant; a gas pipe connecting tube connecting the gas pipe and a plurality of indoor units so that a gas refrigerant flows therethrough; a first gas branch pipe connecting the first indoor unit and the gas pipe connecting tube so that a gas refrigerant flows therethrough; a second gas branch pipe connecting the second indoor unit and the gas pipe connecting tube so that a gas refrigerant flows therethrough; an indoor heat exchanger connecting pipe connecting the first indoor unit and the second indoor unit so that a liquid refrigerant flows therethrough; and a liquid pipe connecting tube connecting the first indoor unit and the liquid pipe so that a liquid refrigerant flows therethrough.

The first indoor unit may include: a first heat exchanger configured to perform heat exchange between indoor air and a refrigerant, a second heat exchanger configured to perform heat exchange between indoor air and a refrigerant and arranged in a stacked fashion with the first heat exchanger; a first indoor fan configured to blow air to the first heat exchanger and the second heat exchanger; a first liquid branch pipe connecting the indoor heat exchanger connecting pipe and the first indoor heat exchanger; a first heat exchanger connecting pipe connecting the first liquid branch pipe and the first heat exchanger of the first indoor heat exchanger; a second heat exchanger connecting pipe connecting the first liquid branch pipe and a second heat exchanger of the first indoor heat exchanger; and a first indoor expansion valve disposed at the second heat exchanger connecting pipe, wherein an opening amount of the first indoor expansion valve is adjusted in response to an input signal from the controller to selectively expand a flowing refrigerant.

The liquid pipe connecting tube may connect the first heat exchanger and a liquid pipe, and the first gas branch pipe may connect the second heat exchanger and the gas pipe.

Since the multi-type air conditioner according to the present disclosure can operate the first heat exchanger as a condenser and the second heat exchanger as an evaporator among the indoor heat exchangers, it is possible to continuously drive the dehumidification mode while maintaining the room temperature within a certain range There are advantages.

In an air-conditioning apparatus, in the case where a compressor is in operation, a fan is in operation, a wind guide plate is in a first state and a second heat exchanger operates as a condenser, when a detected temperature of target space for air-conditioning is higher than a set temperature for the target space and a detected temperature of a second heat exchanger is lower than or equal to a first reference temperature, a controller performs a first control to keep the compressor and the fan in operation and switch the state of the wind guide plate from the first state to a second state.

A multi-air conditioner for heating and cooling may include at least one indoor unit for both cooling and heating including an indoor heat exchanger; an outdoor unit for both cooling and heating including a compressor, a plurality of outdoor heat exchangers, and a switching unit disposed on a discharge side of the compressor to switch a flow of refrigerant; and a distributor disposed between the outdoor unit and the at least one indoor unit, that distributes the refrigerant. The plurality of outdoor heat exchangers in the outdoor unit may include a first heat exchanger, a first end of which is connected to the switching unit, and a second end of which is connected to the distributor; a second heat exchanger disposed under the first heat exchanger, a first end of which is configured to be coupled to or decoupled from the second end of the first heat exchanger, and a second end of which is connected to the distributor; and a third heat exchanger disposed under the second heat exchanger, a first end of which is connected to the discharge side of the compressor, and a second end of which is connected to the indoor unit.

Systems and methods for controlled subcooling of working fluid in a heating, ventilation, air conditioning and refrigeration (HVACR) system through a suction line heat exchanger are disclosed. The suction line heat exchanger may receive a first fluid flow travelling to a suction of the compressor in the HVACR system and second flow of working fluid that is travelling from a heat exchanger receiving the discharge of the compressor to an expansion device. Superheating of the first working fluid may be determined based on temperature measurements prior to and following the suction line heat exchanger. The superheating may be used to control the quantity of the second flow of working fluid introduced into the suction line heat exchanger, for example to maintain superheat that is below a threshold value. These systems may include chillers and heat pump systems, and methods may be applied to chillers or heat pump systems.