Abstract: Methods, systems and apparatuses are directed to a capacity modulating assembly configured to distribute two-phase refrigerant mixture to an evaporator of a HVAC system, such as a micro-channel heat exchanger (MCHEX) evaporator. The capacity modulating assembly may include a plurality of expansion devices. During capacity modulation, at least one of the plurality of expansion devices can be closed so that a refrigerant flow rate through the remaining expansion devices can be maintained. The capacity modulating assembly can include a refrigerant outflow port, which may help direct refrigerant out of the heat exchanger. The capacity modulating assembly can be connected with the MCHEX. The plurality of expansion devices can be configured to extend inside a header of the MCHEX to help distribute refrigerant to the micro-channel tubes of the MCHEX.

Abstract: Methods, systems and apparatuses are directed to a capacity modulating assembly configured to distribute two-phase refrigerant mixture to an evaporator of a HVAC system, such as a micro-channel heat exchanger (MCHEX) evaporator. The capacity modulating assembly may include a plurality of expansion devices. During capacity modulation, at least one of the plurality of expansion devices can be closed so that a refrigerant flow rate through the remaining expansion devices can be maintained. The capacity modulating assembly can include a refrigerant outflow port, which may help direct refrigerant out of the heat exchanger. The capacity modulating assembly can be connected with the MCHEX. The plurality of expansion devices can be configured to extend inside a header of the MCHEX to help distribute refrigerant to the micro-channel tubes of the MCHEX.

Abstract: Methods, systems and apparatuses are directed to a capacity modulating assembly configured to distribute two-phase refrigerant mixture to an evaporator of a HVAC system, such as a micro-channel heat exchanger (MCHEX) evaporator. The capacity modulating assembly may include a plurality of expansion devices. During capacity modulation, at least one of the plurality of expansion devices can be closed so that a refrigerant flow rate through the remaining expansion devices can be maintained. The capacity modulating assembly can include a refrigerant outflow port, which may help direct refrigerant out of the heat exchanger. The capacity modulating assembly can be connected with the MCHEX. The plurality of expansion devices can be configured to extend inside a header of the MCHEX to help distribute refrigerant to the micro-channel tubes of the MCHEX.

Abstract: Methods, systems and apparatuses are directed to a capacity modulating assembly configured to distribute two-phase refrigerant mixture to an evaporator of a HVAC system, such as a micro-channel heat exchanger (MCHEX) evaporator. The capacity modulating assembly may include a plurality of expansion devices. During capacity modulation, at least one of the plurality of expansion devices can be closed so that a refrigerant flow rate through the remaining expansion devices can be maintained. The capacity modulating assembly can include a refrigerant outflow port, which may help direct refrigerant out of the heat exchanger. The capacity modulating assembly can be connected with the MCHEX. The plurality of expansion devices can be configured to extend inside a header of the MCHEX to help distribute refrigerant to the micro-channel tubes of the MCHEX.

Abstract: An adaptive defrost system for a heat pump wherein the time-between-defrosts is continuously updated by multiplying the last time-between-defrosts by a ratio of the desired and actual differences between the pre-defrost and after-defrost saturated coil temperatures. A single thermistor is used for both pre and after-defrost measurements such that no calibration is required.

Abstract: The control box for a refrigeration condensing unit has a heat sink mounted on its rear side between the control box and the coil assembly, the heat sink being in the flow path of the cooling air flowing in thru the coil such that the heat dissipation therefrom is substantially enhanced. The heat sink has a plurality of fins formed on its rear side, with the fins extending across the relatively narrow width of the heat sink such that the cooling air flows over the entire length of each of the fins and provides a substantially uniform velocity profile along the heat sink vertical axis.