There is provided a sublimation defrosting method for removing a frost layer adhering to a cooling surface for cooling a to-be-cooled gas, including a heating/temperature-rising step of heating an adhesion portion of the cooling surface, to which the frost layer adheres, to rise a temperature of the adhesion portion by a heat source located on an adhesion portion side with respect to the frost layer, under a temperature condition below a melting point of the frost layer.

A defrosting apparatus includes: a heating unit including a heater case and a heater, where the heater case defines an inner flow path having an inlet and an outlet at ends thereof, and the heater is mounted in the heater case to heat a working fluid within the inner flow path; and a heat pipe inserted into the inside of the heater case through the inlet and the outlet, and which has at least a part thereof disposed to be adjacent to a cooling pipe of an evaporator such that heat is radiated to the cooling pipe of the evaporator by means of the working fluid at a high temperature that is heated by the heater and then is transferred, where the heater is configured to stop emit heat at a preset temperature or higher, since an electric current is suppressed due to a sharp increase in resistance.

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and a differential pressure sensor having a first pipe, of which one end is positioned on a part where the air is withdrawn to the fan, and a second pipe of which one end is positioned on a part where the air is discharged from the fan.

Defrosting refrigeration equipment meeting the strict requirements for storage of vaccines provided by the Center for Disease Control, California Vaccine for Children, American Academy of Pediatrics, Vaccines for Children (VFC) and the North Dakota Department of Health among others. Vaccine refrigeration storage must maintain consistent temperatures between −58 degrees Fahrenheit and 5 degrees Fahrenheit. The invention utilizes temperature variation moderating heat reservoirs consisting of high specific or latent heat capacity materials to significantly reduce the cycle temperature variation while maintaining the ability to successfully defrost the freezer.

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.

To provide a defrost system capable of preferable defrosting and prevention of generation of icicles on a casing without installing a brine circuit. A defrost system includes a thermosiphon defrost circuit that is provided by being branched from a circulation line, in which, at the time of defrosting, a CO.sub.2 refrigerant staying inside a fin-tube heat exchanger repeats a two-phase change of a gaseous form and reliquefaction, and which forms a CO.sub.2 circulation path together with the fin-tube heat exchanger; electromagnetic opening/closing valves and that are closed at the time of defrosting and set the CO.sub.2 circulation path to a closed circuit; and a first electric heater arranged above the thermosiphon defrost circuit so as to be adjacent to the thermosiphon defrost circuit, and naturally circulates the CO.sub.2 refrigerant in the closed circuit at the time of defrosting.

A method of operating a refrigeration system (20) includes operating the refrigeration system in refrigeration mode. A current access condition into a refrigerated cargo space (22) is detected. At least one heat exchanger (32) in the refrigerated cargo space (22) is directed into a defrost mode during the current access condition. The refrigeration system (20) is directed into a refrigeration mode when the current access condition is no longer detected.

A method for controlling a refrigerator includes providing an initial input value to a heater configured to supply heat to an evaporator, performing a continuous operation of the heater based on the initial input value to increase a temperature of the evaporator to a predetermined temperature, determining a period of time taken to increase the temperature of the evaporator to the predetermined temperature, determining whether the period of time is within a reference period of time, operating the heater based on a first input value that is equal to the initial input value based on a determination that the period of time is outside of the reference period of time, and operating the heater based on a second input value that is less than the initial input value based on a determination that the period of time is within the reference period of time.

In an under counter type refrigerator, when a defrosting period arrives, air of a storage compartment may be supplied towards an evaporator to perform a defrosting operation (natural defrosting operation) for removing frost generated on the evaporator, thereby improving defrosting efficiency and reducing power consumption.

A method for defrosting an evaporator of a sealed system includes determining that a defrost cycle is needed to remove frost from the evaporator and initiating such a defrost cycle. The method further includes determining that the defrost cycle failed to defrost the evaporator and repeating the defrost cycle until the defrost cycle is successful or until a predetermined number of defrost cycles have been performed. After a predetermined number of successive failed defrost cycles, the method includes preventing further operation of the sealed system, e.g., by locking out compressor, until the frost and/or ice build-up is removed.