F25B2700/21172

Air-conditioning apparatus with thermo-off postponement control

It is determined whether thermo-off postponement control is allowed or not on the basis of a current compressor operating frequency when a thermo-off condition is satisfied. If it is determined that thermo-off postponement control is allowed, the thermo-off postponement control in which a lowest operating frequency in an operating frequency range of a compressor is temporarily reduced within a range greater than or equal to a minimum operating frequency of the compressor in use so as to continue an operation. If it is determined that thermo-off postponement control is not allowed, thermo-off of stopping the compressor is performed.

Heat-pump system with refrigerant charge diagnostics

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply-air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

Feed water heating system

Feedwater to be supplied to a feedwater tank via a feedwater path is passed through a waste heat recovery heat exchanger, a supercooler, and a condenser in sequence. A heat source fluid such as heat source water is passed through an evaporator and the waste heat recovery heat exchanger in sequence. The waste heat recovery heat exchanger is an indirect heat exchanger between the feedwater supplied to the feedwater tank via the feedwater path and the heat source fluid having passed through the evaporator. The supercooler is an indirect heat exchanger between the feedwater supplied to the feedwater tank via the feedwater path and a refrigerant supplied from the condenser to an expansion valve.

TWO-STAGE PRESSURE BUILDUP REFRIGERATION CYCLE APPARATUS
20170254569 · 2017-09-07 ·

A two-stage pressure buildup refrigeration cycle apparatus has a low-pressure side compressor, a high-pressure side compressor, and a controller. The controller controls, for improving a COP, the low-pressure side compressor and the high-pressure side compressor in a COP improving operation mode in which a refrigerant discharge capacity of one of the low-pressure side compressor and the high-pressure side compressor is set based on a refrigerant discharge capacity of an other of the low-pressure side compressor and the high-pressure side compressor, when a required level of a refrigeration performance is low. The controller controls the low-pressure side compressor and the high-pressure side compressor in a high performance operation mode in which a refrigerant discharge capacity of the high-pressure side compressor is increased after increasing a refrigerant discharge capacity of the low-pressure side compressor, when the required level of the refrigeration performance is high.

DEVICE MANAGEMENT APPARATUS, HEAT SOURCE SYSTEM, MANAGEMENT APPARATUS, AND DEVICE MANAGEMENT SYSTEM
20220228766 · 2022-07-21 ·

A device management apparatus manages a specific device that changes a state of a heat medium circulating through a heat source system. The device management apparatus receives a state value of the heat medium measured by a sensor included in the heat source system. The device management apparatus prohibits a change operation of a capacity of the specific device based on a parameter related to a change in the state value.

LAUNDRY TREATING APPARATUS
20210404108 · 2021-12-30 ·

Disclosed is a laundry treating apparatus including a cabinet, a drum, a fluid circulator including a compressor sensor, an air circulator including a fan, a driver including a first driver and a second driver, and a controller, wherein a drying operation includes an efficiency increasing process for increasing drying efficiency inside the drum, an efficiency maintaining process for maintaining the drying efficiency, and an efficiency decreasing process for reducing the drying efficiency, wherein the controller performs the drying operation while distinguishing the efficiency increasing process, the efficiency maintaining process, and the efficiency decreasing process from each other through a measured value of the compressor sensor.

Energy efficient refrigerated container operation

A refrigerated storage container is provided and includes a container housing defining an interior, an air conditioner operable to maintain control of temperatures within the interior and a local controller configured to cycle the air conditioner on and off within a time window based on waste heat ingestion from neighboring refrigerated storage containers.

Refrigeration machine control device, turbo refrigeration machine, refrigeration machine control method, and program

A refrigeration machine control device according to an embodiment of the present invention serves to control a turbo refrigeration machine and is equipped with a pressure reduction rate identification unit for identifying a pressure reduction rate at which foaming does not occur in an oil tank, and a pressure adjustment unit for adjusting the pressure of an evaporator on the basis of the identified pressure reduction rate. The pressure reduction rate identification unit is equipped with: a refrigerant precipitation gas volume calculation unit for calculating the volume of refrigerant gas precipitated from lubricating oil when the pressure is reduced at a prescribed pressure reduction rate; and a determination unit for determining whether or not foaming is permissible on the basis of a comparison between the calculated volume and the volume on the surface of the oil in the oil tank.

Method and controller for preventing formation of droplets in a heat exchanger
11346255 · 2022-05-31 · ·

A method for preventing formation of droplets in a heat exchanger, in which a second medium transfers heat to a first. The method is performed by a controller which receives different temperature values (T.sub.1, T.sub.2, T.sub.3) and a pressure (P) value to be used for calculating a boiling point temperature value (T.sub.B) and determining a first temperature difference (ΔT.sub.1) and a second temperature difference (ΔT.sub.2). Generating a flow control signal, for controlling the flow of the first medium into the heat exchanger, based on the first temperature difference (ΔT.sub.1), the second temperature difference (ΔT.sub.2) and the first temperature value T.sub.1 and sending the flow control signal to a regulator device for controlling the flow of the first medium in the heat exchanger.

LOW REFRIGERANT CHARGE DETECTION IN TRANSPORT REFRIGERATION SYSTEM
20220120483 · 2022-04-21 ·

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.