Gree Ultra Heat GMV-VQ72W/A-F, Service Manual

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Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial INSTALLATION
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The nitrogen flow is above 4-6 L/min (pressure of 0.02 to 0.05 MPa) and must be regulated based
on the pipe caliber.

During welding, nitrogen-filling protection must be conducted; otherwise, the remaining substance in
pipeline will cause blockage or leakage to the system (e.g. electronic expansion valve), which will result
in abnormal operation or even damage the compressor.
1.3.6 Requirements on manifold installation
Manifolds are used to divert refrigerant. Requirements on manifold installation are as follows:
(1) Ensure that the manifold is close to the IDU to reduce impact on refrigerant assignment by IDU
branches.
(2) The manifold must be that specified by the manufacture and match with the devices.
(3) Ensure that the manifold model is correct.
(4) Manifolds can be laid in the following ways:
1) Horizontal installation: The three ports must be on the same level. The shaping size and
assembly angle cannot be changed.
2) Vertical installation: The direction can be upwards or downwards. Three ports must be on the
same elevation without inclination.
3) The length of a straight pipe between two manifolds cannot be less than 500 mm
（
19.7inch
）
.
4) The length of a straight pipe before the main pipe port of the manifold cannot be less than 500
mm
（
19.7inch
）
.
5) The length of a straight pipe between the branch of the manifold and the IDU cannot be less than
500 mm
（
19.7inch
）
.