Abstract: The disclosed technology includes devices and systems for an air conditioning unit having a subcooling line. The disclosed technology can include a heat exchanger coil, a bypass line, and a subcooling line. A first valve can be in fluid communication with the subcooling line and a second valve can be in fluid communication with the bypass line. When the air conditioning unit is operating in a cooling mode, the first valve can be configured to permit refrigerant to flow through the subcooling line and the second valve can be configured to prevent refrigerant from flowing through the bypass line. When the air conditioning unit is operating in a heating mode, the first valve can be configured to prevent refrigerant from flowing through the subcooling line and the second valve can be configured to permit refrigerant to flow through the bypass line.

Abstract: A hybrid heating system having a heat recovery apparatus in fluid communication with a heat pump and a furnace is provided. The apparatus recovers heat from flue gas discharged from the furnace and transfers the recovered heat to a stream of refrigerant in the heat pump. The apparatus includes a shell disposed in fluid communication with the furnace and tubes disposed in fluid communication with the shell and the heat pump. The system includes valves for regulating access between the apparatus and the stream of the refrigerant in the heat pump, and a control unit in communication with the valves to regulate access between the apparatus and the heat pump during a heating mode based on operating parameters of the system.

Abstract: A grille assembly for an air handling unit is provided. The grille assembly includes a plurality of first wires aligned in a first plane perpendicular to a direction of flow of air and a plurality of second wires aligned in a second plane perpendicular to the direction of flow of air. The plurality of first wires and the plurality of second wires together form a staggered structure to at least partly enclose an air passage opening of the air handling unit. The second plane is parallel to the first plane and separated by an offset distance along a third plane parallel to the direction of flow of air.

Abstract: Disclosed herein is a flue pipe system comprising a flue pipe, a first electrode, a second electrode, a third electrode, and a voltage supply. The flue pipe can define a fluid flow path through an interior volume of the flue pipe. The voltage supply can be connected to the first electrode, the second electrode, and the third electrode. The voltage supply can form a first electrical circuit comprising the voltage supply, the first electrode, and the third electrode and a second electrical circuit comprising the voltage supply, the second electrode, and the third electrode. The first electrical circuit can form a streamer corona discharge between the first electrode and the third electrode in the interior volume such that the fluid flow path flows therethrough. The second electrical circuit can form a flow of ions between the second electrode and the third electrode along the interior surface of the flue pipe.

Abstract: A header tube assembly is disclosed and can include an outer tube, an inner tube, and a flow valve. Each of the outer and inner tubes can include an open end and a closed end, as well as a plurality of apertures extending through a sidewall of the outer tube and inner tube, respectively. The apertures of the inner tube can permit a flow of refrigerant between an internal volume of the inner tube and a gap between the inner and outer tubes, and the apertures of the outer tube can permit a flow of refrigerant between the internal volume of the outer tube and a plurality of refrigerant circuits in a heat exchanger. The flow valve can be configured to selectively prevent refrigerant from flowing between the gap and the open end of the outer tube, depending on a direction of refrigerant flow through the header tube assembly.

Abstract: A hybrid heating system having a heat recovery apparatus in fluid communication with a heat pump and a furnace is provided. The apparatus recovers heat from flue gas discharged from the furnace and transfers the recovered heat to a stream of refrigerant in the heat pump. The apparatus includes a shell disposed in fluid communication with the furnace and tubes disposed in fluid communication with the shell and the heat pump. The system includes valves for regulating access between the apparatus and the stream of the refrigerant in the heat pump, and a control unit in communication with the valves to regulate access between the apparatus and the heat pump during a heating mode based on operating parameters of the system.

Abstract: The disclosed technology includes devices and systems for an air conditioning unit having a subcooling line. The disclosed technology can include a heat exchanger coil, a bypass line, and a subcooling line. A first valve can be in fluid communication with the subcooling line and a second valve can be in fluid communication with the bypass line. When the air conditioning unit is operating in a cooling mode, the first valve can be configured to permit refrigerant to flow through the subcooling line and the second valve can be configured to prevent refrigerant from flowing through the bypass line. When the air conditioning unit is operating in a heating mode, the first valve can be configured to prevent refrigerant from flowing through the subcooling line and the second valve can be configured to permit refrigerant to flow through the bypass line.

Abstract: A grille assembly for an air handling unit is provided. The grille assembly includes a plurality of first wires aligned in a first plane perpendicular to a direction of flow of air and a plurality of second wires aligned in a second plane perpendicular to the direction of flow of air. The plurality of first wires and the plurality of second wires together form a staggered structure to at least partly enclose an air passage opening of the air handling unit. The second plane is parallel to the first plane and separated by an offset distance along a third plane parallel to the direction of flow of air.