Abstract: An energy efficient heat pump includes a working fluid circuit configured to circulate a working fluid, where the working fluid circuit includes a compressor, a first heat exchanger, a second heat exchanger, a first expansion device, an economizer, and a reversing valve, where the reversing valve is configured to adjust a flow direction of the working fluid through the working fluid circuit. The energy efficient heat pump also includes a first conduit of the working fluid circuit, where the first conduit extends between the first heat exchanger and the second heat exchanger, the economizer is disposed along the first conduit, and the first conduit is configured to direct the working fluid between the first heat exchanger and the second heat exchanger and through the economizer.

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 working fluid circuit and a first conduit of the working fluid circuit, where the first conduit extends between a first heat exchanger and a second heat exchanger of the working fluid circuit. The energy efficient heat pump also includes a compressor disposed along the working fluid circuit, where the compressor is configured to direct a working fluid along the working fluid circuit, and the compressor includes a suction port and an injection port. The energy efficient heat pump further includes an injection conduit extending from the first conduit to the injection port of the compressor, where the injection conduit includes an expansion device, and the injection conduit is configured to direct a portion of the working fluid from the working fluid circuit, through the expansion device, and to the injection port.

Abstract: A heating, ventilation, and air conditioning (HVAC) system includes a primary heat transfer circuit having a first heat exchanger fluidly coupled to an ambient environment and a compressor fluidly coupled to the first heat exchanger and configured to circulate a refrigerant through the primary heat transfer circuit. The HVAC system also includes a secondary heat transfer circuit having a second heat exchanger fluidly coupled to a thermal load and a pump fluidly coupled to the second heat exchanger and configured to circulate a heat transfer fluid through the secondary heat transfer circuit, where the heat transfer fluid is a non-volatile or inert fluid.

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 having a plurality of compressors configured to direct a working fluid along a working fluid circuit of the heat pump, a suction conduit configured to direct the working fluid to the compressor system, a first suction conduit portion extending from the suction conduit to a first compressor of the plurality of compressors, a second suction conduit portion extending from the suction conduit to a second compressor of the plurality of compressors, and a control valve disposed along the suction conduit between the first suction conduit portion and the second suction conduit portion.

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 along a working fluid circuit of the heat pump. The compressor system includes a first compressor configured to direct the working fluid along a first portion of the working fluid circuit having a first expansion device to operate the heat pump in a cooling mode and includes a second compressor configured to direct the working fluid along a second portion of the working fluid circuit having a second expansion device to operate the heat pump in a heating mode. The 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 the cooling mode and to operate the second compressor and suspend operation of the first compressor in the heating mode.

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: A heat pump for a heating, ventilation, and air conditioning (HVAC) system includes a compressor system configured to direct a refrigerant flow along a refrigerant circuit of the heat pump. The compressor system includes a first compressor and a second compressor arranged in parallel with one another relative to a direction of the refrigerant flow through the compressor system, the first compressor includes a first volume index, and the second compressor includes a second volume index different from the first volume index. The heat pump also includes a controller communicatively coupled to the first compressor and the second compressor and configured to selectively operate the first compressor, the second compressor, or both based on an operating mode the heat pump.