Abstract: A pressure monitoring system is disclosed. The pressure monitoring system includes a battery powered sensing unit mounted on a partition between a first space and a second space. The sensing unit senses differential pressure between the first space and the second space separated by the door, determines position of the door, and wirelessly communicate differential pressure and door position to a building management system.

Abstract: An energy efficient heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a compressor system configured to direct a working fluid flow along a working fluid circuit of the energy efficient heat pump. The compressor system includes a first compressor configured to direct the working fluid flow in a first direction along the working fluid circuit and a second compressor configured to direct the working fluid flow in a second direction along the working fluid circuit, opposite the first direction. The energy efficient heat pump also includes a controller communicatively coupled to the first compressor and the second compressor, where the controller is configured to operate the first compressor and suspend operation of the second compressor in a cooling mode of the energy efficient heat pump and to operate the second compressor and suspend operation of the first compressor in a heating mode of the energy efficient heat pump.

Abstract: An energy efficient heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a compressor system configured to direct a working fluid flow along a working fluid circuit of the energy efficient heat pump. The compressor system includes a first compressor configured to direct the working fluid flow in a first direction along the working fluid circuit and a second compressor configured to direct the working fluid flow in a second direction along the working fluid circuit, opposite the first direction. The energy efficient heat pump also includes a controller communicatively coupled to the first compressor and the second compressor, where the controller is configured to operate the first compressor and suspend operation of the second compressor in a cooling mode of the energy efficient heat pump and to operate the second compressor and suspend operation of the first compressor in a heating mode of the energy efficient heat pump.

Abstract: An energy efficient heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a compressor system configured to direct a working fluid flow along a working fluid circuit of the energy efficient heat pump. The compressor system includes a first compressor configured to direct the working fluid flow in a first direction along the working fluid circuit and a second compressor configured to direct the working fluid flow in a second direction along the working fluid circuit, opposite the first direction. The energy efficient heat pump also includes a controller communicatively coupled to the first compressor and the second compressor, where the controller is configured to operate the first compressor and suspend operation of the second compressor in a cooling mode of the energy efficient heat pump and to operate the second compressor and suspend operation of the first compressor in a heating mode of the energy efficient heat pump.

Abstract: An energy efficient heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a compressor system configured to direct a working fluid flow along a working fluid circuit of the energy efficient heat pump. The compressor system includes a first compressor configured to direct the working fluid flow in a first direction along the working fluid circuit and a second compressor configured to direct the working fluid flow in a second direction along the working fluid circuit, opposite the first direction. The energy efficient heat pump also includes a controller communicatively coupled to the first compressor and the second compressor, where the controller is configured to operate the first compressor and suspend operation of the second compressor in a cooling mode of the energy efficient heat pump and to operate the second compressor and suspend operation of the first compressor in a heating mode of the energy efficient heat pump.

Abstract: An apparatus includes a high side heat exchanger, a load, a compressor, a belt, a first bin, a second bin, and a controller. The high side heat exchanger removes heat from a refrigerant. The load uses the refrigerant to cool an enclosed space. The compressor compresses the refrigerant. The first and second bins are coupled to the belt and positioned within the enclosed space. The controller receives a first message, determines that the first bin should be selected, and cycles the belt to move the first bin to a retrieval location within the enclosed space. The controller also receives a second message, determines that the second bin should be selected, and cycles the belt to move the second bin to the retrieval location.

Abstract: An apparatus includes a high side heat exchanger, a load, a compressor, a belt, a first bin, a second bin, and a controller. The high side heat exchanger removes heat from a refrigerant. The load uses the refrigerant to cool an enclosed space. The compressor compresses the refrigerant. The first and second bins are coupled to the belt and positioned within the enclosed space. The controller receives a first message, determines that the first bin should be selected, and cycles the belt to move the first bin to a retrieval location within the enclosed space. The controller also receives a second message, determines that the second bin should be selected, and cycles the belt to move the second bin to the retrieval location.

Abstract: An apparatus includes a high side heat exchanger, a load, a compressor, a belt, a first bin, a second bin, and a controller. The high side heat exchanger removes heat from a refrigerant. The load uses the refrigerant to cool an enclosed space. The compressor compresses the refrigerant. The first and second bins are coupled to the belt and positioned within the enclosed space. The controller receives a first message, determines that the first bin should be selected, and cycles the belt to move the first bin to a retrieval location within the enclosed space. The controller also receives a second message, determines that the second bin should be selected, and cycles the belt to move the second bin to the retrieval location.

Abstract: An apparatus includes a high side heat exchanger, a load, a compressor, a belt, a first bin, a second bin, and a controller. The high side heat exchanger removes heat from a refrigerant. The load uses the refrigerant to cool an enclosed space. The compressor compresses the refrigerant. The first and second bins are coupled to the belt and positioned within the enclosed space. The controller receives a first message, determines that the first bin should be selected, and cycles the belt to move the first bin to a retrieval location within the enclosed space. The controller also receives a second message, determines that the second bin should be selected, and cycles the belt to move the second bin to the retrieval location.

Abstract: A zoned HVAC system comprises an HVAC unit including a climate control system and an air mover. In addition, the system comprises a supply air duct in fluid communication with the outlet of the HVAC unit. Further, the system comprises a return air duct in fluid communication with the inlet of the HVAC unit. Still further, the system comprises a plurality of zones positioned between the supply air duct and the return air duct. Moreover, the system comprises a bypass duct extending between the supply air duct and the return air duct. The bypass duct includes an active bypass damper having an open position, a closed position, and a plurality of partially opened positions. The system also comprises a control device configured to control the position of the bypass duct.

Abstract: An air handling unit has a blower configured to selectively move air from an air inlet of the air handling unit to an air outlet of the air handling unit along an airflow direction extending from the blower to the air outlet, a heat exchanger disposed within the air handling unit between the inlet and the outlet, the heat exchanger has a thermal conductor, an evaporator tube thermally conductively joined to the thermal conductor, and a subcooler tube thermally conductively joined to the thermal conductor. An expansion device provides fluid communication between the evaporator tube and the subcooler tube and a drain pan disposed within the air handling unit upstream relative to the at least one subcooler tube and positioned in a geometrical footprint of at least a portion of the drain pan as the drain pan is viewed from an upstream position in the airflow direction.

Abstract: A zoned HVAC system comprises an HVAC unit including a climate control system and an air mover. In addition, the system comprises a supply air duct in fluid communication with the outlet of the HVAC unit. Further, the system comprises a return air duct in fluid communication with the inlet of the HVAC unit. Still further, the system comprises a plurality of zones positioned between the supply air duct and the return air duct. Moreover, the system comprises a bypass duct extending between the supply air duct and the return air duct. The bypass duct includes an active bypass damper having an open position, a closed position, and a plurality of partially opened positions. The system also comprises a control device configured to control the position of the bypass duct.

Abstract: A zoned HVAC system comprises an HVAC unit including a climate control system and an air mover. In addition, the system comprises a supply air duct in fluid communication with the outlet of the HVAC unit. Further, the system comprises a return air duct in fluid communication with the inlet of the HVAC unit. Still further, the system comprises a plurality of zones positioned between the supply air duct and the return air duct. Moreover, the system comprises a bypass duct extending between the supply air duct and the return air duct. The bypass duct includes an active bypass damper having an open position, a closed position, and a plurality of partially opened positions. The system also comprises a control device configured to control the position of the bypass duct.

Abstract: A method of reducing a cyclical loss coefficient of an HVAC system efficiency rating of an HVAC system includes operating the HVAC system using a recorded electronic expansion valve position of an electronic expansion valve of the HVAC system, discontinuing operation of the HVAC system, and resuming operation of the HVAC system using an electronic expansion valve position that allows greater refrigerant mass flow through the expansion valve as compared to the recorded electronic expansion valve position.

Abstract: An air handling unit has a blower configured to selectively move air from an air inlet of the air handling unit to an air outlet of the air handling unit along an airflow direction extending from the blower to the air outlet, a heat exchanger disposed within the air handling unit between the inlet and the outlet, the heat exchanger has a thermal conductor, an evaporator tube thermally conductively joined to the thermal conductor, and a subcooler tube thermally conductively joined to the thermal conductor. An expansion device provides fluid communication between the evaporator tube and the subcooler tube and a drain pan disposed within the air handling unit upstream relative to the at least one subcooler tube and positioned in a geometrical footprint of at least a portion of the drain pan as the drain pan is viewed from an upstream position in the airflow direction.

Abstract: An HVAC system includes an electronic expansion valve having a movable obturator with a truncated tip and a port configured to selectively receive the truncated tip. An electronically controlled expansion valve includes a movable obturator with a truncated tip and a port configured to selectively receive the truncated tip. A method of operating a heat pump HVAC system includes providing an electronically controlled expansion valve comprising an obturator having a truncated tip and flowing refrigerant through the valve.

Abstract: A zoned HVAC system comprises an HVAC unit including a climate control system and an air mover. In addition, the system comprises a supply air duct in fluid communication with the outlet of the HVAC unit. Further, the system comprises a return air duct in fluid communication with the inlet of the HVAC unit. Still further, the system comprises a plurality of zones positioned between the supply air duct and the return air duct. Moreover, the system comprises a bypass duct extending between the supply air duct and the return air duct. The bypass duct includes an active bypass damper having an open position, a closed position, and a plurality of partially opened positions. The system also comprises a control device configured to control the position of the bypass duct.

Abstract: In at least some embodiments, a hybrid heating system includes a heat pump and an auxiliary furnace. The system also includes a controller coupled to the heat pump and the auxiliary furnace. The controller, in response to receiving a heat request, selects either the heat pump or the auxiliary furnace based on an economic balance point algorithm.

Abstract: A vapor compression air conditioning system includes a motor operated expansion valve and control unit including sensors for determining the amount of superheat of the working fluid at or adjacent to the compressor inlet. Expansion valve position is adjusted to maintain a predetermined amount of superheat. The sensors may sense working fluid evaporator temperature and temperature downstream of the evaporator. Dual motor operated expansion valves may be disposed in the working fluid conduit between the heat exchangers in a reversible system. In operation, the expansion valve position may be set as a function of ambient temperature, a previous position, and predetermined superheat requirements to minimize liquid ingestion by the compressor.