An embodiment of a probe includes a sensor and a support. The sensor is operable to provide an indication of a thickness of a frozen substance that has accumulated between the sensor and a cooling fin of a cooling unit, and the support is operable to hold the sensor spaced apart from the cooling fin. For example, a defrost controller may use an embodiment of such a probe to monitor an amount of frost build up on the fin or fins of a cooling unit (e.g., a refrigeration or freezer unit) so that the controller may initiate a defrost cycle only when warranted. Such a probe may be more reliable than other defrost-detection techniques, and such a defrost controller may increase the cooling and energy efficiencies of a cooling unit as compared to a cooling unit having a conventional defrost controller.

An embodiment of a probe includes a sensor and a support. The sensor is operable to provide an indication of a thickness of a frozen substance that has accumulated between the sensor and a cooling fin of a cooling unit, and the support is operable to hold the sensor spaced apart from the cooling fin. For example, a defrost controller may use an embodiment of such a probe to monitor an amount of frost build up on the fin or fins of a cooling unit (e.g., a refrigeration or freezer unit) so that the controller may initiate a defrost cycle only when warranted. Such a probe may be more reliable than other defrost-detection techniques, and such a defrost controller may increase the cooling and energy efficiencies of a cooling unit as compared to a cooling unit having a conventional defrost controller.

The present disclosure discloses a defrosting device, including a heating unit provided at a lower side of an evaporator, and configured to heat working fluid therein; and a plurality of heat pipes, both end portions of which are connected to an inlet and an outlet of the heating unit, respectively, and at least part of which are disposed adjacent to a cooling tube of the evaporator to emit heat to the cooling tube due to high temperature working fluid heated and transferred by the heating unit, wherein the plurality of heat pipes are configured with a first heat pipe and a second heat pipe disposed to form two rows on a front portion and a rear portion of the evaporator, respectively, and the first heat pipe and the second heat pipe are formed in different lengths.

A probe includes a sensor and a support. The sensor is operable to provide an indication of a thickness of a frozen substance that has accumulated between the sensor and a cooling fin of a cooling unit, and the support is operable to hold the sensor spaced apart from the cooling fin. When a defrost controller uses such a probe to monitor an amount of frost build up on the fin or fins of a cooling unit (e.g., a refrigeration unit or freezer unit), the defrost controller can initiate a defrost cycle only when warranted, e.g., only when the thickness of the built-up frost equals or exceeds a threshold thickness.