Abstract: The present disclosure provides a louvered fin including a leading edge, a trailing edge, and a surface extending between the leading edge and the trailing edge. The surface defines a first set of holes along a first axis, a second set of holes along a second axis and offset from the first set of holes, and a third set of holes along a third axis and offset from the second set of holes. Each of the first axis, the second axis, and the third axis extends substantially parallel to a longitudinal axis of the fin. A first offset distance between the second and first set of holes is greater than a second offset distance between the third and second set of holes. The second and the third set of holes define a substantially obtuse trapezoidal matrix.

Abstract: A valve system is disclosed for use with a compressor, an indoor heat exchange coil, and an outdoor heat exchange coil. The valve system may include a first reversible valve and a second reversible valve. The first reversible valve may be configured to receive heated refrigerant from the compressor. The second reversible valve may be configured to provide cooled refrigerant to the compressor. In a heating mode, the first reversible valve may be configured to provide the heated refrigerant to the indoor heat exchange coil. In the heating mode, the second reversible valve may be configured to receive the cooled refrigerant from the outdoor heat exchange coil.

Abstract: A compression refrigeration system includes a switch to select between a plurality of operation modes of a metering device that controls a rate of flow of a refrigerant to an evaporator of the compression refrigeration system. Each operation mode is associated with a respective refrigerant. Further, the compression refrigeration system includes a reference database that comprises pressure-temperature data associated with a plurality of refrigerants. Furthermore, the compression refrigeration system includes a valve adjustment engine that is communicatively coupled to the switch and the reference database. The valve adjustment engine controls the metering device based on an operation mode of the metering device that is selected using the switch. The operation mode is selected based on a refrigerant with which the compression refrigeration system is currently charged.

Abstract: Disclosed herein is a heat exchanger apparatus comprising a heat exchanger tube having an inlet valve and an outlet valve. When the valves are open, the refrigerant can flow through the heat exchanger tube, and when the valves are closed, refrigerant can be stored in the heat exchanger tube, thereby reducing the effective heat exchange surface area of the heat exchanger apparatus.

Abstract: A combination domestic hot water and space heating system is disclosed. The system includes two refrigerant circuits, one dedicated to heating potable water in a water storage tank and one dedicated to heating a condenser used to heat a space within a building. A controller sends output signals to valves to vary refrigerant flow into the first refrigerant circuit and/or the second refrigerant circuit. The variation in refrigerant flow can be provided by a single multi-directional valve, one or more valves placed at a first end of each refrigerant circuit, and/or one or more electronic expansion valves placed at the end of each refrigerant circuit. Portions of the system can be placed into a single housing, thereby reducing installation costs and labor.

Abstract: Disclosed herein is a heat exchanger apparatus comprising a heat exchanger tube having an inlet valve and an outlet valve. When the valves are open, the refrigerant can flow through the heat exchanger tube, and when the valves are closed, refrigerant can be stored in the heat exchanger tube, thereby reducing the effective heat exchange surface area of the heat exchanger apparatus.

Abstract: A compression refrigeration system includes a switch to select between a plurality of operation modes of a metering device that controls a rate of flow of a refrigerant to an evaporator of the compression refrigeration system. Each operation mode is associated with a respective refrigerant. Further, the compression refrigeration system includes a reference database that comprises pressure-temperature data associated with a plurality of refrigerants. Furthermore, the compression refrigeration system includes a valve adjustment engine that is communicatively coupled to the switch and the reference database. The valve adjustment engine controls the metering device based on an operation mode of the metering device that is selected using the switch. The operation mode is selected based on a refrigerant with which the compression refrigeration system is currently charged.