A refrigerant cycle apparatus includes a refrigerant circuit that circulates a refrigerant, and a leak sensor that detects a refrigerant leaking from the refrigerant circuit, in which the refrigerant cycle apparatus includes, as an operating mode, a recovery mode for recognizing occurrence of an abnormality in the leak sensor and recovering a refrigerant to a predetermined location in the refrigerant circuit.

A refrigerator can include a storage compartment having a storage space and an opening; at least one door coupled to the storage compartment to open and close a part of the storage compartment; a compressor configured to provide the storage compartment with freezing capacity or cooling capacity; a processor configured to control driving of the compressor; and a memory operably connected to the processor and configured to store code to cause the processor to in response to recognizing placement of an item in the storage space, determine whether the item is an overload item to generate a determination result; and control the driving of the compressor to adjust a temperature of the storage space based on the determination result.

A control method and device for an air conditioner outdoor unit, an outdoor unit and an air conditioner are provided. The outdoor unit has a compressor, a first sensor for detecting an air exhaust pressure of the compressor, and a second sensor for detecting an air return pressure of the compressor. According to the method, a target pressure value is determined; an air exhaust pressure value detected by the first sensor or an air return pressure value detected by the second sensor is periodically obtained as a first pressure value; and the frequency of the compressor is adjusted according to the first pressure value and the target pressure value.

A vapor compression system includes a first conduit fluidly coupling a liquid collection portion of a condenser and an evaporator, where the first conduit is configured to direct a first flow of refrigerant from the condenser to a first inlet of the evaporator and a second conduit fluidly coupling the liquid collection portion of the condenser and the evaporator, where the second conduit is configured to direct a second flow of refrigerant from the condenser to a second inlet of the evaporator via gravitational force, and where the first inlet is disposed above the second inlet relative to a vertical dimension of the evaporator.

A refrigeration cycle apparatus controller includes an expansion-valve controller configured to output an opening-degree command for an expansion valve based on a deviation between a discharge temperature of refrigerant discharged from a compressor and a set discharge temperature, and at least two control parameters including a proportionality coefficient and an integral coefficient, a flow-rate-correction-coefficient calculator configured to calculate a flow-rate correction coefficient from a refrigerant flow rate of refrigerant circulating through a refrigerant circuit and a preset flow-rate reference value, and a coefficient corrector configured to calculate the proportionality coefficient by correcting a preset proportionality-coefficient reference value based on the flow-rate correction coefficient, and calculate the integral coefficient by correcting a preset integral-coefficient reference value based on the flow-rate correction coefficient. The proportionality coefficient and the integral coefficient are calculated such that a variation range of the integral coefficient rate is larger than a variation range of the proportionality coefficient.

Described is a vector control system for a vapor compression circuit. The vector control system may monitor the vapor compression circuit and adjust the speed of one or more motors to increase efficiency by taking into account the torque forces placed on a compressor motor.

A method includes measuring a saturated suction temperature, receiving actual temperature value reflective of the measured saturated suction temperature, and determining whether the actual temperature value is less than a first pre-determined minimum threshold temperature value. If the actual temperature value is less than the first pre-determined minimum threshold temperature value, initiating a timer to operate for a pre-determined time interval. Determining whether the actual temperature value is less than a second pre-determined minimum threshold temperature value and if the actual temperature value is less the second pre-determined minimum threshold temperature value, initiating the timer to operate for a modified time interval. If the timer has expired, the operation of the compressor is modified.

A system for modulating hot gas reheat operation of a heating, ventilation, and/or air conditioning (HVAC) system with multiple compressors, wherein the HVAC system is configured to regulate air provided to multiple zones. The system includes a controller configured to respond to a call for dehumidification in the absence of a call for cooling by sequentially energizing a first compressor of the multiple compressors in a reheat mode of the first compressor, energizing a second compressor of the multiple compressors in a cooling mode of the second compressor, energizing a third compressor of the multiple compressors in a reheat mode of the third compressor initially at full capacity, and energizing a fourth compressor of the multiple compressors in a cooling mode of the fourth compressor.

An air conditioner has a refrigerant circuit filled with a predetermined amount of a refrigerant, the circuit being formed of an outdoor unit and an indoor unit connected to each other by refrigerant piping, the outdoor unit having a compressor, an outdoor heat exchanger, and an expansion valve, the indoor unit having an indoor heat exchanger. The conditioner has an estimation model that estimates an amount of remaining refrigerant remaining in the circuit by using at least rotation frequency of the compressor, refrigerant discharge temperature at the compressor, heat exchanger temperature, degree of opening of the expansion valve, and outside air temperature, of operation state quantities indicating operation states during operation. The indoor heat exchanger has a sensor that is provided at an indoor heat exchanger intermediate portion connecting a first indoor heat exchanger port and a second indoor heat exchanger port to each other.

An HVAC system includes a compressor, condenser, and evaporator. A sensor measures a value associated with the refrigerant in the condenser or the evaporator, and a controller is communicatively coupled to the compressor and the sensor. The controller determines, based on an operational history the compressor, that pre-requisite criteria are satisfied for entering a sensor validation mode. After determining the pre-requisite criteria are satisfied, an initial sensor measurement value is determined. Following determining the initial sensor measurement value, the compressor is operated according to a sensor-validation mode. Following operating the compressor according to the sensor-validation mode for at least a minimum time, a current sensor measurement value is determined. The controller determines whether validation criteria are satisfied for the current sensor value. In response to determining that the validation criteria are satisfied, the controller determines that the sensor is validated.