Gree FGR25Pd/DNa-X Service Manual page 44

 If units you want to monitor are already connected, and able to communicate normally, with correct
COM and protocal, then you may click "Connect" to enter the interface of numbers. Otherwise,
connect in accordance with the connection diagram shown below.
 COM selection: the serial port in your computer can be detected automatically. You just need to
select your desired serial port.
Duct type split Air conditioner Inverter Series
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