US 12,352,485 B2
Systems and methods for heat pump systems
Michael F. Taras, Spring, TX (US)
Assigned to Daikin Comfort Technologies Manufacturing, L.P., Waller, TX (US)
Filed by Daikin Comfort Technologies Manufacturing, L.P., Waller, TX (US)
Filed on Aug. 24, 2022, as Appl. No. 17/821,934.
Prior Publication US 2024/0068724 A1, Feb. 29, 2024
Int. Cl. F25B 49/02 (2006.01); F25B 13/00 (2006.01); F25B 41/20 (2021.01)
CPC F25B 49/022 (2013.01) [F25B 13/00 (2013.01); F25B 41/20 (2021.01)] 11 Claims
OG exemplary drawing
 
1. A method of operating a heat pump heating, ventilation, and air conditioning (heat pump HVAC) system operable to use a refrigerant to heat an indoor space in a heating mode or cool an indoor space in a cooling mode, the method comprising:
compressing the refrigerant with a compressor;
flowing the refrigerant in a refrigerant circuit including an indoor heat exchanger, a first expansion device, and an outdoor heat exchanger, wherein the refrigerant flows through the first expansion device in a first direction in the cooling mode and in a second direction, opposite the first direction, in the heating mode;
flowing a first flow of refrigerant upstream from the outdoor heat exchanger in the heating mode;
flowing a second flow of refrigerant downstream from the outdoor heat exchanger in the heating mode;
transferring heat between the first flow and the second flow via an internal heat exchanger to precool the first flow before entering an ejector in the heating mode;
combining the first flow and the second flow into a combined flow within the ejector in the heating mode, wherein the first flow includes lower enthalpy than the second flow, and wherein the combined flow includes an enthalpy between the first flow and the second flow; and
flowing at least a portion of the combined flow to the compressor in the heating mode.