VARIABLE REFRIGERANT HVAC SYSTEM WITH INDIVIDUAL DEFROST

摘要

Provided are a heat pump system (100) and a method of controlling the same. The heat pump system (100) comprises a plurality of outdoor units (105A, 105B) operable in a plurality of operation modes in fluid communication with one or more indoor units (125) via a heat transfer circuit (200). A first and a second of the plurality of outdoor units (105A, 105B) includes a compressor (205A, 205B), and a first flow control device (220A, 220B) between the compressor (205A, 205B) and an outdoor heat exchanger (225A, 225B) in a first flow direction and between the compressor (205A, 205B) and a second flow control device (250A, 250B) in a second flow direction. In a first state, the first flow control device (220A, 220B) permits refrigerant flow to the outdoor heat exchanger (225A, 225B). In a second state, the first flow control device (220A, 220B) permits refrigerant flow to the second flow control device (250A, 250B). The second flow control devices (250A, 250B) of the first and second of the plurality of outdoor units (105A, 105B) are individually controllable to set the first and/or second of the plurality of outdoor units (105A, 105B) to a defrost mode.