Gree FGR20Pd/DNa-X Owner's Manual page 26

(8) For the convenience of troubleshooting during debugging, unit shall be
connected to a PC with applicable debugging software. Make sure unit's
real-time data can be checked through this computer. The installation and
connection of debugging software can be found in the Service Manual.
(9) Before test operation, make sure unit is power on and compressor has
been preheated for more than 8 hours. Touch the unit to check whether
it's normally preheated. If yes, start test operation. Otherwise, compressor
might be damaged.
(10) If the LED digital tube on main board displays, then input the startup
password. For operation details, please see the instructions for the
function of startup password.
4.2.2 Test Operation and Debugging
Once the unit is energized and turned on for the first time, the display tube of
outdoor unit displays "A0", which indicates debugging standby status. At this time,
hold SW3 button successively for 5s on the main module to enter into the automatic
debugging, and then the engineering debugging will perform according to the set
procedures. Step3(conformation of outdoor unit' quantity) and step4(conformation
of indoor unit' quantity) should be confirmed manually by pressing "SW3", while
other procedures will be performed automatically. Once the debugging for each step
is finished, "oC" will be displayed; once all engineering debugging are finished, "oF"
will be displayed, which indicates the unit is under standby status.
Ducted Type Split Air-Conditioner Units(Inverter Series)
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