US 12,405,024 B2
Heat pump control systems and methods
Andrew Leroy Hjortland, Stoughton, WI (US); and Roy Randall Crawford, Blanchard, OK (US)
Assigned to TYCO FIRE & SECURITY GMBH, Neuhausen am Rheinfall (CH)
Filed by Johnson Controls Tyco IP Holdings LLP, Milwaukee, WI (US)
Filed on Jan. 26, 2023, as Appl. No. 18/101,988.
Claims priority of provisional application 63/304,415, filed on Jan. 28, 2022.
Prior Publication US 2023/0243544 A1, Aug. 3, 2023
Int. Cl. F24F 11/84 (2018.01); F24F 1/08 (2011.01)
CPC F24F 11/84 (2018.01) [F24F 1/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A heat pump for a heating, ventilation, and air conditioning (HVAC) system, comprising:
a compressor system configured to direct a refrigerant flow along a refrigerant circuit of the heat pump, wherein the compressor system comprises 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 comprises a first volume index, and the second compressor comprises a second volume index different from the first volume index; and
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 of the heat pump,
wherein the controller is configured to operate the first compressor and the second compressor in response to a determination that a temperature differential between a temperature within a space conditioned by the heat pump and a set point temperature of the space is greater than a threshold amount.
 
11. A heat pump for a heating, ventilation, and air conditioning (HVAC) system, comprising:
a first compressor configured to direct refrigerant flow along a refrigerant circuit of the heat pump, wherein the first compressor comprises a first built-in volume ratio;
a second compressor configured to direct refrigerant flow along the refrigerant circuit of the heat pump, wherein the second compressor comprises a second built-in volume ratio; and
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 of the heat pump,
wherein the controller is configured to operate the first compressor and suspend operation of the second compressor in a cooling mode of the heat pump and configured to operate the second compressor and suspend operation of the first compressor in a heating mode of the heat pump,
wherein the first compressor and the second compressor are arranged in parallel with one another relative to a direction of refrigerant flow through the refrigerant circuit, and the second built-in volume ratio is greater than the first built-in volume ratio.
 
17. A heat pump for a heating, ventilation, and air conditioning (HVAC) system, comprising:
a refrigerant circuit;
a compressor system disposed along the refrigerant circuit and configured to direct a refrigerant along the refrigerant circuit, wherein the compressor system comprises a first compressor and a second compressor arranged in parallel with one another relative to a flow direction of the refrigerant through the compressor system, the first compressor comprises a first volume index, and the second compressor comprises a second volume index greater than the first volume index;
a first heat exchanger disposed along the refrigerant circuit and configured to place the refrigerant in a heat exchange relationship with a supply air flow;
a second heat exchanger disposed along the refrigerant circuit and configured to place the refrigerant in a heat exchange relationship with an ambient air flow;
a reversing valve configured to direct the refrigerant from the compressor system to the second heat exchanger in a cooling mode of the heat pump and configured to direct the refrigerant from the compressor system to the first heat exchanger in a heating mode of the heat pump; and
a controller communicatively coupled to the first compressor and the second compressor and configured to operate the first compressor and suspend operation of the second compressor in the cooling mode.