From CoolAutomation Wiki
Connecting to Gree VRF System
CoolMasterNet should be connected in the same way as original Gree Communication Module like ME30-00/E2 or ME30-24/E2(M). Connection can be done:
- On Outdoor Unit. On Outdoor PCB there are special connectors for Outdoor-Indoor(s) wiring and Communication Module connection. Connectors can be 3 or 4 pins wide, usually marked as -- A B --. Try to find communication cable going from Outdoor to Indoor(s). The signal wires in this cable are usually BROWN and ORANGE. Near the connector of this cable on Outdoor PCB where should similar free connector(s) that can be used for CoolMasterNet.
- Wedge into Outdoor-Indoors(s) cable break. Just cut the cable in desired place and wedge into. Make sure to keep wires isolated after such surgery.
- On Indoor Unit. Same way as on Outdoor PCB if additional connector is available.