Gree GMV5 Series Service Manual page 104

commissioning personnel and assistants.
1.3 Preparations of Commissioning Tools and Instruments
a. Make sure that the following tools or instruments are prepared before commissioning.
b. Make sure that the commissioning software is correct before commissioning.
The professional aftersales commissioning software provided by GREE should be used for
commissioning of GREE VRF system.
c. Make sure that all required files and parameter records are prepared.
Step 2: Pre-commissioning Check
Installation environment check covers the heat exchange environment of unit and electromagnetic
radiant components. All requirements should comply with national and local electrical standards. For any
installation incompliance, records should be made for providing an analysis basis during refrigerating
system testing.
2.2 Installation Appearance Check
Installation appearance check covers whether pipeline installation complies with specifications, whether
refrigerant pipes and condensing drainage pipes are thermal insulated, and whether
Refrigerant pipes should be tidily installed, with outdoor and indoor disperse pipes leaning in the
required scope. For any installation incompliance, records should be made for providing an analysis
basis during refrigerating system testing.
Refrigerant pipes and condensing drainage pipes should not be exposed. If any pipe is exposed, an
immediate amendment is required to avoid serious loss.
2.3 Refrigerating System Check
1) Before commissioning, make sure that the stop valve of each module reaches the maximum opening
degree. Check whether there is any refrigerator oil leakage around the valve. If there is, immediately
check for leakage with soap bubbles or leak detectors. If confirming that leakage exists, immediately
stop commissioning and solve the problem before continuing commissioning.
2) Check system refrigerants before startup.
Before the system is started, connect the liquid-tube valve of ODU with a high pressure gauge and the
air-tube valve of ODU with a low pressure gauge, and then read their values. In this case, high pressure
and low pressure of the system should be in balance status, and the difference between the saturation
temperature corresponding to the balanced pressure value and the environment temperature (the higher
in outdoor and indoor temperatures is taken as environment temperature) should not be larger than 5°C.
If the difference is larger than 5° C , it is required to check the ODU for leakage.
Note: Guarantee that the system has never been started before this test. Otherwise, the high pressure
value will be over-higher than the environment temperature or the low pressure value will be over-lower
than the environment temperature.
Example:
The outdoor environment temperature is 30° C and the indoor environment temperature is 28° C . The
pressure gauges connected with the system show that the high pressure value is 28° C and the low
pressure value is 27° C . The difference between the o utdoor environment temperature and either
pressure value is less than 5° C . It indicates that the system standby pressure is normal.
GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
101