An aircraft galley chiller is adapted to fit within a service column of the aircraft. The condenser is elongated, oriented vertically, and includes a bank of fans to increase airflow. The evaporator is also elongated and includes a bank of fans. The evaporator and condenser are oriented with the same plane to produce a footprint that fits within the service column. The evaporator includes a heater element to periodically heat and de-ice the evaporator.

An aircraft galley chiller is adapted to fit within a service column of the aircraft. The condenser is elongated, oriented vertically, and includes a bank of fans to increase airflow. The evaporator is also elongated and includes a bank of fans. The evaporator and condenser are oriented with the same plane to produce a footprint that fits within the service column. The evaporator includes a heater element to periodically heat and de-ice the evaporator.

A freezer and method of operating a freezer are provided with an adaptive defrost cycle. The freezer includes a controller that operates the freezer to: provide cooling to a cabinet via an evaporator during periodic operational cycles, monitor a time elapsed since a most recent defrost cycle, determine whether the time elapsed is greater than a current defrost interval, and perform a defrost cycle if so. The controller varies the current defrost interval between a first, larger time value and a second, smaller time value based on a plurality of trigger signals in response to various operating characteristics of the freezer monitored by sensors. After each defrost cycle is completed, the current defrost interval is reset to the first, larger time value.

The present invention provides a system and method for an improved multistage, cascade refrigeration system using hot gas defrost to rid the evaporator of ice build-up which accumulates over time, while the air in the evaporator enclosure remains below the freezing point of water. The present invention thus provides greater defrost flexibility with increased ease of design and implementation than current refrigeration systems, which allows for more robust hot gas defrost function for multistage refrigeration systems, such that it is unaffected by temperature changes of the condensing fluid (ambient air temperature for air cooled condensers, water temperature for water cooled condensers), and can be readily adapted to any refrigerant suitable for a selected temperature range.

A dehumidifying system and method for reducing humidity in ambient air is disclosed. The system includes a circulation unit, a refrigeration unit, a condensate receptacle for receiving condensate generated by the refrigeration unit, a controller to control both the circulation and refrigeration units, and wherein the controller receives input from one or more ambient sensors configured to sense ambient conditions, and a user interface configured to receive input from a user. The system implements variable speed control within the circulation and/or refrigeration unit to maximize efficiency or capacity under a current threshold, and enables the system to delay the need for defrost cycling during low temperature operation.

A dehumidifying system and method for reducing humidity in ambient air is disclosed. The system includes a circulation unit, a refrigeration unit, a condensate receptacle for receiving condensate generated by the refrigeration unit, a controller to control both the circulation and refrigeration units, and wherein the controller receives input from one or more ambient sensors configured to sense ambient conditions, and a user interface configured to receive input from a user. The system implements variable speed control within the circulation and/or refrigeration unit to maximize efficiency or capacity under a current threshold, and enables the system to delay the need for defrost cycling during low temperature operation.

An improved HVAC system and method for simultaneously controlling the temperature and humidity of an indoor space while providing high quantities of outdoor air is described herein. The HVAC system of the present invention utilizes a heating source positioned in the supply passageway between an energy recovery wheel and a dehumidification wheel in order to control the temperature and humidity of air supplied to the indoor space while preventing frost build-up on the energy recover wheel. By positioning a heating source between the energy recovery wheel and a dehumidification wheel, the system is able to prevent frost accumulation on the energy recovery wheel during winter operation while also increasing the relative humidity of the supply air.

A refrigerator includes a cabinet configured to form a first storage chamber and a second storage chamber, a first evaporator configured to cool the first storage chamber, a first fan configured to circulate air in the first storage chamber to the first evaporator and the first storage chamber, a second evaporator configured to cool the second storage chamber, a compressor configured to be connected to the first evaporator and the second evaporator, a second fan configured to circulate air in the second storage chamber to the second evaporator and the second storage chamber; a refrigerant valve configured to guide refrigerant to the first evaporator or the second evaporator, and a controller configured to perform a plurality of modes sequentially to defrost the second evaporator.

A refrigerator includes a cabinet configured to form a first storage chamber and a second storage chamber, a first evaporator configured to cool the first storage chamber, a first fan configured to circulate air in the first storage chamber to the first evaporator and the first storage chamber, a second evaporator configured to cool the second storage chamber, a compressor configured to be connected to the first evaporator and the second evaporator, a second fan configured to circulate air in the second storage chamber to the second evaporator and the second storage chamber; a refrigerant valve configured to guide refrigerant to the first evaporator or the second evaporator, and a controller configured to perform a plurality of modes sequentially to defrost the second evaporator.

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.