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

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GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
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5. During the installation of the ODU, induced and exhaust pipes must be connected. In addition, the
aperture opening rate of shutters must be at least 80%, and the angle between the shutters and the
horizontal plane should be less than 20°. Requirements for installing exhaust air duct are as follows:
i. Basic requirement for connecting an ODU to static pressure ventilating duct
When an ODU needs to be connected to the static pressure ventilating duct, the ventilating duct must be
reasonably designed. The pressure loss caused by the ventilating duct must be calculated. In addition, a
proper type of ventilating duct is necessary. To connect he static pressure ventilating duct to the ODU,
three basic parts are required: (1) ODU; (2) canvas; and (3) steel-plate ventilating duct. The ODU must
be interconnected with the ventilating duct through canvas to prevent abnormal vibration and noise
generated by the steel-plate ventilating duct. The joint part must be tightly sealed with tin foil to avoid air
leakage.
ii. Preparations for connecting an ODU to static pressure ventilating duct
(1) The ODU is installed properly based on the unit installation requirement.
(2) The steel-plate ventilating duct is designed based on the unit and engineering requirement, and is
installed properly according to the engineering standards.
(3) Based on the unit dimensions and the size of steel-plate ventilating duct, prepare materials such as
canvas casing, tin foil, steel bar and tapping screw, as well as tools such as hand-operated electric drill,
air screw driver and screwdriver.
iii. Basic operation of connecting an ODU to static pressure ventilating duct
Two methods are available to connect an ODU to static pressure ventilating duct.
Method 1: Reserve the unit top case. Detailed operations are as follows:
a) Install the ODU (2) and steel-plate ventilating duct (1). Use an air screw driver or screwdriver to
unfasten the tapping screws that fixing the top case component (3), and then remove the top case
component. Take out the grille from the top of the top case component and leave the top case.
b) Put the canvas casing inside out (4). Cover one end of the canvas casing over the unit
downward until the canvas end face is aligned with the unit or a bit higher than the top of the unit. Then,
put the top case back (3) and tightly press the canvas casing (4). Use tapping screws to fix the top case
onto the unit (3).
c) Pull up the canvas casing reversely (4) and use the steel bar (5) to press the canvas casing
tightly onto the counter flange of the steel-plate ventilating duct (1). Use a hand-operated electric drill to
drill holes and fasten the parts by using tapping screws.
d) Use the tin foil to seal the joints and check the joints' reliability.