An apparatus using a heat pump includes a refrigerant circuit and a heat medium circuit. The refrigerant circuit is allowed to perform a first operation, in which a load-side heat exchanger is used as a condenser, and a second operation, in which the load-side heat exchanger is used as an evaporator. A container is provided to a suction pipe provided between a refrigerant flow switching device and a compressor. To the heat medium circuit, an overpressure protection device and a refrigerant leakage detecting device are connected. When leakage of refrigerant into the heat medium circuit is detected, the refrigerant flow switching device is switched to a second state, an expansion device is set to a closed state, and the compressor is made in operation. When a requirement for ending the operation of the compressor is satisfied after the leakage of the refrigerant into the heat medium circuit is detected, the compressor is set to a stopped state, and the refrigerant flow switching device is switched to a first state.

A refrigeration appliance includes a freezer compartment. An ice maker return duct fluidly couples an ice maker compartment and the freezer compartment. A pressure sensor is positioned within the freezer compartment and is configured to detect a pressure differential between the freezer compartment and an external environment. A fan is positioned within the ice maker return duct and is configured to be activated when the pressure within the freezer compartment is lower than the external environment.

Disclosed is a heat pump system for an electric vehicle including an outdoor fan configured to blow air to an outdoor heat exchanger, a coolant temperature sensor installed at a coolant line and configured to detect a temperature of a coolant circulating in a power train module or a battery, an outdoor heat exchange sensor installed on one side of the outdoor heat exchanger and configured to detect an outdoor heat exchanger outlet pressure defined as a pressure of a refrigerant passing through the outdoor heat exchanger, and a compressor inlet sensor installed on an intake side of a compressor and configured to detect a compressor inlet temperature defined as a temperature of the refrigerant flowing into the compressor. Whether frost sticking occurs may be determined based on information detected by the coolant temperature sensor, the outdoor heat exchange sensor, and the compressor inlet sensor.

A method of defrosting an indoor coil in a refrigeration system including, while the system is operating in the refrigeration mode, with a controller of the refrigeration system, determining a defrost commencement time at which the refrigeration system is to commence operating in the defrost mode. With the controller, one or more defrost energy conservation processes are initiated prior to the defrost commencement time, to decrease a rate at which thermal energy is transferred from the refrigerant in the outdoor coil to ambient air around the outdoor coil. The defrost energy conservation process continues until a defrost energy conservation termination criterion is satisfied, at which time the defrost energy conservation process is terminated. Upon termination of the defrost energy conservation process, operation of the refrigeration system in the defrost mode is commenced.

A heat pump cycle includes a compressor, a heat exchanger, a gas-liquid separator, and an outdoor heat exchanger. The heat pump cycle includes a main circuit connecting the compressor, the heat exchanger, the gas-liquid separator, and the outdoor heat exchanger such that refrigerant flows therethrough. The heat pump cycle includes an exhaust-heat recovery heat exchanger, and an exhaust-heat recovery circuit forming a flow path leading to the compressor not through the outdoor heat exchanger but through the exhaust-heat recovery heat exchanger. The heat pump cycle includes an expansion valve that is disposed upstream of the exhaust-heat recovery heat exchanger in the exhaust-heat recovery circuit and expands the refrigerant such that the refrigerant changes from liquid phase to gas phase in the exhaust-heat recovery heat exchanger.

An HVAC system includes, an electronic expansion valve (EEV), and a controller in communication with the EEV. The controller determines a minimum EEV setpoint position value based on a comparison of a superheat error value to a setpoint error threshold. The controller determines a maximum EEV setpoint position value based on a comparison of a second superheat error value to a second setpoint error threshold. The controller calculates an average setpoint value based on the maximum EEV setpoint position value and the minimum EEV setpoint position value. The controller configures the EEV to a position corresponding to the average setpoint value and operate the EEV for a predetermined amount of time. The controller operates the EEV according to a PID algorithm.

A heat source system includes a plurality of heat source apparatuses each including a refrigerant circuit including a water heat exchanger; a water supply header pipe; a water return header pipe; a plurality of pumps; a bypass pipe configured to connect the water supply header pipe and the water return header pipe; a bypass valve; a differential pressure gauge configured to measure a water pressure difference between pressure of water supplied to the load and pressure of water returning from the load; and a controller, where the controller determines the number of heat source apparatuses to be operated, among the plurality of heat source apparatuses, from an amount of heat generated and an amount of heat required, and controls, according to a result of determination, one of the operating frequency of the pump and an opening degree of the bypass valve such that the water pressure difference falls within a target range.

In an air conditioner, a control section controls at least the indoor expansion valve. The indoor expansion valve has a degree of opening that is controllable. The control section has a condensate formation suppressing control mode and a normal heating control mode. The condensate formation suppressing control mode is performed in a case where a predetermined condensate formation condition is satisfied. The predetermined condensate formation condition relates to generation of condensate formation on the connecting section. The normal heating control mode is performed in cases other than the case where the predetermined condensate formation condition is satisfied. The control section increases the opening degree of the indoor expansion valve when the condensate formation suppressing control mode is performed compared to a case when the normal heating control mode is performed.

A method for air-conditioning of watercraft and the like comprising the use of a device with: an electronically controlled variable-r.p.m. compressor, a main gas/water condenser (5), at least one environmental heat-exchanger (3) with an electronically controlled fan (14), at least one electronically controlled expansion valve (8), and at least one first electronic control unit (4) programmed for calculating continuously a temperature deviation detected (DeltaT=T_ad-T_a), and as a function of said temperature deviation regulating in combination, the r.p.m. of the compressor (1), opening of the flow valve (8), and the r.p.m. of the fan of the heat-exchanger (3).

An apparatus for air-conditioning of watercraft and the like comprising: an electronically controlled variable-r.p.m. compressor, a main gas/water condenser (5), at least one environmental heat-exchanger (3) with an electronically controlled fan (14), at least one electronically controlled expansion valve (8), and at least one first electronic control unit (4) programmed for calculating continuously a temperature deviation detected (DeltaT=T_adT_a), and as a function of said temperature deviation regulating in combination, the r.p.m. of the compressor (1), opening of the flow valve (8), and the r.p.m. of the fan of the heat-exchanger (3).