A method of initiating a defrost cycle using a controller of a heat pump system includes measuring a temperature of an evaporator coil and determining whether the temperature of the evaporator coil is less than a freezing temperature. Responsive to a determination that the temperature of the evaporator coil is less than the freezing temperature, determining whether a current dew point temperature of air is greater than the temperature of the evaporator coil. Responsive to a determination that the current dew point temperature of air is greater than the temperature of the evaporator coil, calculating a frost-collection rate. Determining whether the frost-collection rate is greater than a frost-collection-rate threshold, and, responsive to a determination that the frost-collection rate is greater than the frost-collection-rate threshold, initiating a defrost cycle.

A refrigeration system includes a refrigerated cavity, a first compression system, and a second compression system. The refrigeration system further includes a controller configured to operate the refrigeration system in a first mode in which the first compression system and the second compression system operate to cool the refrigerated cavity. The refrigeration system is further configured to selectively operate the refrigeration system in a second mode in which a refrigerant discharged from the second compressor is routed through the first evaporator to defrost the first evaporator.

A heat pump water heater can include a water tank and a refrigerant circuit that can be in fluid communication with an evaporator coil, a condenser coil, and a compressor. The heat pump water heater can include a fan configured to move air across the evaporator coil, a temperature sensor, and a controller. The controller can be configured to receive temperature data from the temperature sensor and, in response to the temperature data indicating a temperature less than a predetermined temperature threshold, output instructions for the compressor to deactivate and the fan to move air across the evaporator coil.

An air-conditioning device includes: a compressor; an outdoor heat exchanger; an evaporating unit configured to evaporate refrigerant a heater unit configured to heat the air by using the heat of the refrigerant a liquid receiver arranged at the downstream side of the outdoor heat exchanger and a restrictor mechanism provided between the heater unit and the outdoor heat exchanger, wherein, in an operation state in which the flow of the refrigerant is restricted by the restrictor mechanism and heat is released in the heater unit, a first operation mode and a second operation mode are switched, the first operation mode being set such that the liquid-phase refrigerant is stored in the liquid receiver and the gaseous-phase refrigerant is guided to the compressor and the second operation mode being set such that the liquid-phase refrigerant stored in the liquid receiver is guided to the evaporating unit.

A dual redundant cooling system for a container is provided. The dual redundant cooling system includes a first cooling unit and a second cooling unit. The first cooling unit is positioned in a first cabinet attached to the container. The first cooling unit includes a first controller operating a first cooling loop to cool an interior of the container. The second cooling unit is positioned in a second cabinet attached to the container and adjacent the first cabinet. The second cooling unit includes a second controller operating a second cooling loop to cool the interior of the container. The first cooling unit and the first cooling loop are separate from the second cooling unit and the second cooling loop. The first controller and the second controller communicate a switch signal between each other so that either the first cooling unit is a primary cooling unit operating the first cooling loop or the second cooling unit is the primary cooling unit operating the second cooling loop. The switch signal switching the primary cooling unit. The system interface box positioned in the second cabinet and connected to the first cooling unit and the second cooling unit. The system interface box has a first switch adapted to power on or power off the first cooling unit and a second switch adapted to power on or power off the second cooling unit.

There is provided a vehicle air conditioning apparatus capable of removing frost formed on an outdoor heat exchanger at the same time as cooling of a battery. The vehicle air conditioning apparatus performs the operation in a first battery cooling mode, a second battery cooling mode, or a solo battery cooling mode, when it is determined that the battery needs to be cooled and also determined that the frost formed on the outdoor heat exchanger needs to be removed. By this means, it is possible to cool the battery and melt the frost formed on the outdoor heat exchanger at the same time by the battery cooling operation, and therefore it is possible to reduce the power consumption compared to the case where the battery cooling operation and the defrosting operation are performed individually.

An apparatus includes a flash tank that stores a refrigerant, a first load that uses the refrigerant to cool a first space, second and third loads, first and second compressors, and a high side heat exchanger configured to remove heat from the refrigerant. During a first mode of operation: the second load uses the refrigerant to cool a second space, the third load uses the refrigerant to cool a third space, the second compressor compresses the refrigerant from the second and third loads, and the first compressor compresses the refrigerant from the first load and the second compressor. During a second mode of operation, the second compressor compresses the refrigerant from the second load and directs the compressed refrigerant to the third load to defrost the third load.

The resent invention provides a refrigerator comprising: a cabinet having a storage chamber; a door for opening and closing the storage chamber; a case having a discharge port through which air is discharged to the storage chamber; an evaporator provided inside the case and for supplying cold air by means of heat exchange with air; a fan installed on the discharge port and for generating the airflow discharging to the storage chamber the air which has been heat exchanged in the evaporator; and a differential pressure sensor having a first pipe, of which one end is positioned on a part where the air is withdrawn to the fan, and a second pipe of which one end is positioned on a part where the air is discharged from the fan.

an ice making system includes a tank that stores a medium to be cooled, an ice making machine that cools the medium and makes ice, a pump that circulates the medium between the tank and the ice making machine, a de-icing mechanism that heats the medium and melts the ice in the ice making machine, and a control device that controls operations of the ice making machine, the pump, and the de-icing mechanism. The ice making machine includes a cooling chamber that cools the medium, an inflow port through which the medium flows into the cooling chamber, and a discharge port through which the medium is discharged from the cooling chamber. The control device activates the de-icing mechanism when a pressure difference between a pressure of the medium at the inflow port and a pressure of the medium at the discharge port exceeds a predetermined value.

A cooling and heating system for a motor vehicle comprises a heat pump, a controller, a low temperature radiator in thermal communication with the heat pump, a passenger cabin heat exchanger in thermal communication with the heat pump, and a defrost system comprising a bypass coolant loop in selective fluid communication with the low temperature radiator. When in the heating mode, the controller opens a solenoid valve and activates a coolant heater in the bypass coolant loop upon detecting operation of the heat pump outside of a predetermined normal operating range and upon detecting an ambient temperature below a predetermined temperature. The controller de-activates the coolant heater upon detecting operation of the heat pump within the predetermined normal operating range. The controller may also de-activate close the solenoid upon detecting operation of the heat pump within the predetermined normal operating range.