An air conditioner according to an embodiment includes: a compressor configured to compress a refrigerant; an indoor heat exchanger configured to convert a vapor refrigerant into a liquid refrigerant in a heating mode; an outdoor heat exchanger configured to convert a liquid refrigerant into a vapor refrigerant in the heating mode; a main pipe connecting the indoor heat exchanger to the outdoor heat exchanger; an injection pipe branching from the main pipe and connecting to an injection port of the compressor; an injection valve installed on the injection pipe and configured to control a flux of the refrigerant flowing to the injection pipe; and a controller configured to calculate a target discharge superheat (DSH) based on a correlation between a compression coefficient, a compressor frequency, and a DSH that are represented by an operating condition , and control a current DSH based on the target DSH.

An air conditioner and a control method for the same, the air conditioner including an air conditioning unit including a compressor, a first heat exchanger, an expansion valve, and a second heat exchanger; and a controller configured to obtain enthalpy of a refrigerant flowing in the air conditioning unit, obtain an air conditioning capacity using a circulation amount of the refrigerant and the obtained enthalpy of the refrigerant, obtain efficiency based on the obtained air conditioning capacity and supplied power, and control the air conditioning unit according to the obtained efficiency.

A steady-state data processing method includes resetting a cumulative change of target determination data and a data detection period as 0; obtaining the detected target data; calculating the cumulative change of the target data. When the calculated cumulative change of the target data is less than a preset threshold, adjusting the data detection period, or when the calculated cumulative change of the target data is not less than the preset threshold, recording a data detection period. When the recorded data detection period is less than a preset time threshold, determining a target data result obtained in the period as unsteady-state data of the device; or when the recorded data detection period is not less than the preset time threshold, determining the target data obtained in the data detection period as steady-state data.

A control method, a control device for starting an air conditioner, a storage medium, and an air conditioner are disclosed. The method includes the step of acquiring current temperature variation information of a weather in an environment of the air conditioner and current startup parameters of the air conditioner. The method further includes the step of controlling operation parameters of the air conditioner according to the current temperature variation information and the current startup parameters of the air conditioner.

A heating, ventilation, air conditioning, and refrigeration (HVACR) system is disclosed. The HVACR system includes a refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, an expansion device, and an evaporator fluidly connected. A controller is electronically connected to the compressor. The controller is configured to prevent the compressor from operating at a speed that is less than a minimum speed limit. A lubricant separator has an inlet fluidly connected between the compressor and the condenser and a plurality of outlets. A first of the plurality of outlets is fluidly connected to the condenser. A second of the plurality of outlets is fluidly connected to one or more components of the compressor to provide a lubricant to the one or more components.

A refrigeration system includes a compressor, a condenser, a heat transfer component, and a refrigerant loop arranged to allow a flow of a refrigerant fluid. The compressor, the condenser, and the heat transfer component are connected in the refrigerant loop. The system further includes a bypass path extending between an output side of the compressor in the refrigerant loop and an input side of the heat transfer component in the refrigerant loop. A bypass valve is connected in the bypass path. A control circuit is in communication with the bypass valve. The control circuit is configured to open the bypass valve to allow the refrigerant fluid to pass to the heat transfer component thereby increasing the refrigerant fluid provided to the heat transfer component and artificially increasing a load on the refrigeration system. Other examples refrigeration system and examples methods are also disclosed.

There is disclosed a refrigeration system comprising a refrigeration circuit that includes a compressor, a condenser, an expansion valve and an evaporator. A condenser fan of the refrigeration system is configured to operate, under the control of a controller, at a condenser fan speed that is set based on a current refrigeration demand on the system.

An economizer control system includes a compressor including a compression area, a piston chamber, and an economizer inlet configured to receive economizer vapor into the compression area via a flow path that extends between the economizer inlet and the compression area. At least a portion of the flow path traverses the piston chamber. The economizer control system also includes a piston disposed within the piston chamber and configured to contact the economizer vapor. The piston is moveable between an open position that opens the flow path and a closed position that closes the flow path. Additionally, the economizer control system includes a biasing system configured to apply force to the piston to bias the piston toward the closed position.

An air-conditioning system includes a heat-source device that includes a compressor and a heat-source-side heat exchanger, a relay device that includes a pump and an intermediate heat exchanger, and a plurality of indoor units that each include a load-side heat exchanger. The air-conditioning system includes a refrigerant circuit through which refrigerant circulates and a heat medium circuit through which a heat medium circulates. The air-conditioning system includes a flow rate detection unit configured to detect flow rate information associated with a flow rate of a heat medium that flows through each of the plurality of indoor units and a controller configured to control the compressor and the pump. The controller controls operation of at least either the compressor or the pump on the basis of the flow rate information detected by the flow rate detection unit.

A system and method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack and determines compressor rack power consumption data. A condensing unit controller monitors and controls operation of the condensing unit and determines condensing unit power consumption data. The system controller receives the compressor rack power consumption data and the condensing unit power consumption data, determines a total power consumption of the refrigeration or HVAC system, determines a predicted power consumption or a benchmark power consumption for the refrigeration system, compares the total power consumption with the predicted power consumption or the benchmark power consumption, and generates an alert based on the comparison.