GREE GMV5E DC INVERTER VRF UNITS SERVICE MANUAL
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Check the rubbers for oil separator, gas separator, oil balancer, and drying filter. If they are lost
during transportation, cover the parts with tape to keep the compressor dry and airtight inside.
Note:
Compressor lubricant must be kept completely airtight. Hitachi compressors use special
lubricant FVC68D whose moisture absorption capability is high. Requirements on air-tightness of these
compressors are higher.
2. Prepare other materials.
(1) Prepare nitrogen. Prepare enough nitrogen. They will be used during welding. Nitrogen pressure
should be 2.0 MPa at least.
(2) Prepare welding rods. In addition to ordinary welding rods, you should also prepare special
weldin
g rods (containing 5% or more silver). Compressors’ inlets and outlets are made of copper
plated steels, which require special welding rods and materials.
(3) Prepare gases for welding. Oxygen and acetylene of proper amount should be determined with
consideration of actual welding positions. Try to finish the welding task once. Avoid repeated
welding.
(4) Prepare tools, including hexagon, diagonal pliers, combination pliers, needle nose pliers,
multimeter, pressure gauge, Phillips screwdriver, flathead screwdriver, wrenches (at least two),
PVC insulation tape, and tielines (multiple).
Step 8: Install a new gas/liquid separator.
Note:
If a faulty compressor needs replacement, the gas/liquid separator needs replacement as well.
This is to avoid abnormality from happening inside the gas separator, and affecting system safety and
reliability.
