Gree GMV-224WM/B-X, Service Manual

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GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
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2. If the refrigerant is proved satisfactory, fill refrigerant of the combined amount of the rated amount
(specified on the nameplate) and the calculated refrigerant loss amount.
For a multi-modular unit system, if only the refrigerant of an ODU is drawn out, add 80% refrigerant of
the rated fill amount (specified on the nameplate of the ODU) and start the system for a debugging test.
Step 16: Install electric parts.
Install the electric box and connect various parts to the electric box by referring to the marks made
beforehand and the wiring diagram on the back of the box. Wire the compressors and corresponding
electric heating belts.
Note: Wires should be checked against the wiring diagram beforehand so that they can be
connected correctly.
Step 17: Start for debugging.
Start the units and set them to run in refrigerating full-start, refrigerating single-start, heating full-start,
and heating single-start modes respectively. Duration for each running mode should be 30 minutes at
least. After the debug, analyze data and adjust the unit system, to ensure indexes of the entire system.
For details about each index, please consult after-sale persons and technicians.
III. Cautions on Compressor Drive
Replacement
1. Disconnect the power supply of the system. Set a multimeter to the AC voltage gear and measure
voltage between two of the lines (L1, L2, L3, and N). The measuring result should be 0 V
(sometimes, multimeters may be faulty and read false values). Set a mark beside the power supply
for warning.
2. Measure compressor drive DC bus voltage between two wire terminals of P, U, V, W and N. Set the
multimeter to the DC voltage gear and measure the voltage between P and N. The voltage should
be lower than 36 V. If no multimeter is available, wait for 20 minutes before performing the steps
below.
Note: The blue squares
indicate pads.
3. Disconnect all lines of the compressor drive, including: compressor line; communication line
between the master unit and the drive; communication line between the compressor drive and fan
drive; compressor drive output 18 VDC; bridge rectifier output P; bridge rectifier output N;
compressor drive output 540 VDC; r
eactor‘s wiring terminal; bridge rectifier input AC inlead;
compressor drive‘s mains termi
nal. See the figure below: