Patent ID: 11965672
Assignee: DAIKIN APPLIED AMERICAS INC.
Field: Thermal processes and apparatus (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. A heat pump system comprising:
a compressor, the compressor delivering compressed refrigerant to a discharge line and receiving a refrigerant from a suction line;
a usage side heat exchanger;
a heat source side heat exchanger arranged to exchange heat between a heat transfer medium and refrigerant flowing therethrough;
an expansion valve;
a main refrigerant flow control valve switchable between
a cooling mode in which refrigerant is configured to flow from the discharge line through part of a refrigerant circuit, to the heat source side heat exchanger, to the expansion valve and then to the usage side heat exchanger, and
a heating mode in which refrigerant is configured to flow from the discharge line through part of the refrigerant circuit to the usage side heat exchanger, to the expansion valve and then to the heat source side heat exchanger;

a hot gas reheat heat exchanger connected in the refrigerant circuit;
a fan disposed to direct an airflow across the usage side heat exchanger and the hot gas reheat heat exchanger into a target space;
a receiver connected in the refrigerant circuit, the receiver being configured such that refrigerant flows through the receiver to an inlet side of the expansion valve when the main refrigerant flow control valve is in the cooling mode, and configured such that refrigerant does not flow to the receiver when the main refrigerant control valve is in the heating mode; and
at least one secondary refrigerant flow control valve switchable between
a first mode in which refrigerant is configured to flow from the discharge line to the main refrigerant flow control valve,
a second mode in which at least some refrigerant is configured to flow from the discharge line to the hot gas reheat heat exchanger and then flows to the main refrigerant flow control valve, and
a third mode in which refrigerant is configured to flow both
from the discharge line to the hot gas reheat heat exchanger and then flows to the main refrigerant flow control valve, and
from the discharge line to the main refrigerant flow control valve without flowing through the hot gas reheat heat exchanger,

the refrigerant circuit and the main and secondary refrigerant flow control valves being configured such that refrigerant flows to the usage side heat exchanger and the hot gas reheat heat exchanger when the main refrigerant flow control valve is in the heating mode, and
the refrigerant circuit and the main and secondary refrigerant flow control valves being configured such that the refrigerant flows to the hot gas reheat heat exchanger before flowing to the heat source side heat exchanger when the main refrigerant flow control valve is in the cooling mode.