An airplane is provided. The airplane includes an environmental control system coupled to an engine and an inlet. The engine provides a bleed. The inlet provides a fresh medium. The environmental control system includes a compressing device comprising a compressor and a turbine. The environmental control system also includes a moisture removal circuit that separately removes moisture from each of the first and second mediums prior to combining the first medium and the second medium to form mixed air.

In an embodiment, a method of preventing evaporator coil freeze in a heating, ventilation and air conditioning (HVAC) system is performed by a controller in the HVAC system. The method includes determining a reference saturated suction temperature (SST) via a sensor disposed in relation to an evaporator coil in the HVAC system. The method also includes determining whether the reference SST is below a minimum SST threshold. The method also includes, responsive to a determination that the reference SST is below the minimum SST threshold, increasing a discharge air temperature (DAT) setpoint.

A thermoelectric assembly includes a thermoelectric module having a hot side and a cold side, where a heat sink is coupled with the hot side of the thermoelectric module and a cold sink is coupled with the cold side of the thermoelectric module. A metalized gasket is disposed between the heat sink and the cold sink and extends around a portion of the thermoelectric module. A vapor barrier may be attached to and cover an outer surface of the metalized gasket.

A cooling unit for cold air generation, in particular for snow-making systems, has a mechanically operating de-icing device which comprises at least one rotary shaft (6), which extends between two tube layers (5) transversely to the refrigerant guide tubes and is displaceable in the longitudinal direction of the refrigerant guide tubes (4), and a rotary drive for rotating the rotary shaft (6). The removal elements (16) are designed as rotary elements which are fastened to the rotary shaft (6) and which remove the ice and frost build-up from the refrigerant guide tubes (4) by means of a rotary movement.

A cooling unit for cold air generation, in particular for snow-making systems, has a mechanically operating de-icing device which comprises at least one rotary shaft (6), which extends between two tube layers (5) transversely to the refrigerant guide tubes and is displaceable in the longitudinal direction of the refrigerant guide tubes (4), and a rotary drive for rotating the rotary shaft (6). The removal elements (16) are designed as rotary elements which are fastened to the rotary shaft (6) and which remove the ice and frost build-up from the refrigerant guide tubes (4) by means of a rotary movement.

Disclosed is a carbon dioxide heat pump evaporator, comprising side evaporators having defrosting water flow channels formed thereon, an evaporator tray which is arranged at the bottoms of the side evaporators and is used for supporting the side evaporators, and a defrosting drainage system, wherein the defrosting drainage system comprises a plurality of defrosting electric heating tubes inserted into the side evaporators, water receiving gutters which are connected to the defrosting water flow channels, gutter electric heating mechanisms for heating the water receiving gutters, and drainage pipes which are connected to the water receiving gutters and are provided with conduit electric heating tracing bands; and the evaporator tray, the water receiving gutters and the drainage pipes are sequentially arranged from top to bottom. The carbon dioxide heat pump evaporator is suitable for low-temperature areas, especially for areas of extreme cold, and has the characteristics of a short defrosting time, smooth drainage, etc.

Disclosed is a carbon dioxide heat pump evaporator, comprising side evaporators having defrosting water flow channels formed thereon, an evaporator tray which is arranged at the bottoms of the side evaporators and is used for supporting the side evaporators, and a defrosting drainage system, wherein the defrosting drainage system comprises a plurality of defrosting electric heating tubes inserted into the side evaporators, water receiving gutters which are connected to the defrosting water flow channels, gutter electric heating mechanisms for heating the water receiving gutters, and drainage pipes which are connected to the water receiving gutters and are provided with conduit electric heating tracing bands; and the evaporator tray, the water receiving gutters and the drainage pipes are sequentially arranged from top to bottom. The carbon dioxide heat pump evaporator is suitable for low-temperature areas, especially for areas of extreme cold, and has the characteristics of a short defrosting time, smooth drainage, etc.

A determination device able to determine a cause of generation of gas with a simple configuration is provided. The determination device includes a pressure gauge that detects pressure in a gas storage chamber that stores non-condensable gas generated in an absorber of an absorption refrigerator, and a hydrogen sensor that detects an amount of hydrogen discharged from the gas storage chamber. Further, a determining unit determines a cause of generation of the non-condensable gas stored in the gas storage chamber based on a detection result of the hydrogen sensor and a detection result of the pressure gauge.

Air conditioner units and methods of operating the same are provided. A method of operating an air conditioner unit includes determining a fan speed as a function of a compressor speed of a variable speed compressor of the air conditioner unit. The method also includes activating a variable speed fan of the air conditioner unit at the fan speed. An air conditioner unit may include a controller, and the controller may be configured for performing the method.

In an embodiment, a method of preventing evaporator coil freeze in a heating, ventilation and air conditioning (HVAC) system includes determining a reference saturated suction temperate (SST) via a sensor disposed in relation to an evaporator coil in the HVAC system, where the HVAC; system is operating in reheat dehumidification mode. The method also includes determining whether the reference SST is below a minimum SST threshold. The method also includes, responsive to a determination that the reference SST is below the minimum SST threshold, determining a decreased compressor speed. The method also includes modulating a variable-speed compressor in the HVAC system in correspondence to the decreased compressor speed.