Gree GMVVQ224WM/C-X Owner's Manual page 57

GMV Heat Recovery DC Inverter VRF
(5) The mode exchange box must be connected in series and the last mode exchange box must
be connected with a matching resistance (provided among the accessory parts of outdoor
unit). Connect the matching resistance to the D1, D2 terminals of communication wiring board
of mode exchange box.
(6) Adopt the one-to-one connection method for the connection between heat pump mode
converter and downstream indoor unit. Each branch is corresponding to one communication
terminal. "1D1, 1D2" indicates the terminal position of communication wire for the
downstream indoor unit of the first branch; "2D1, 2D2" indicates the terminal position of
communication wire for the downstream indoor unit of the second branch and by this analogy.
Please note that there's corresponding mark at the corresponding connection place of copper
pipe for each indoor unit on branch.
(7) If there're multiple indoor units at one branch of heat pump mode exchange box, the
communication wires of indoor units should adopt series connection. Please note that
operation mode for the indoor units at the same branch should be consistent under any
circumstances.
(8) Communication wire can't be connected for the downstream indoor units at the different
branches of heat pump converter.
(9) When the mode exchange box connects to an indoor unit whose capacity is larger than 16kw,
keep the indoor unit and either one of the corresponding two branches connected. Please
confirm that these two branches are corresponding to the 1st number of SA2 DIP switch that
directs to digital terminal on main board.
(10) The indoor unit must be connected in series, and the last indoor unit must be connected to
the communication matching resistor (provided in the outdoor unit parts list).
(11) Please refer to the relevant manual for the centralized controller wiring method and settings.
3.9.6 Communication Connection Between Indoor Unit and Wired Controller
There are four types of connection between the indoor unit and wired controller, as shown in the
following figure:
Fig.3.9.10 One wired controller controls one IDU Fig.3.9.11 Two wired controllers control one IDU
Fig.3.9.12One wired controller control multiple IDUs
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