Lennox VEPS075N432K, User Manual

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DC Inverter Multi VRF System
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4.2.6 Dimension of Pipe between Indoor Branch and IDU
Dimension of pipe between indoor branch and IDU should be consistent with the dimension of
indoor pipe.
Fig. 9
Rated capacity of IDU C(kW) Gas pipe (mm) Liquid pipe (mm)
C≤2.8 Φ9.52 Φ6.35
2.8<C≤5.0 Φ12.7 Φ6.35
5.0<C≤14.0 Φ15.9 Φ9.52
14.0<C≤16.0 Φ19.05 Φ9.52
16.0<C≤28.0 Φ22.2 Φ9.52
NOTE: If the distance between IDU and its nearest branch is over 10m, then the liquid pipe of IDU
(rated capacity ≤5.0kW) shall be enlarged.
4.3 Installation of Connection Pipe
4.3.1 Precautions for the Installation of Connection Pipe
(1) Conform to the following principles during pipe connection: Connection pipe should be as short
as possible, so is the height difference between indoor and outdoor units. Keep the number of
bends as little as possible. Radius of curvature should be as large as possible.
(2) Weld the connection pipe between indoor and outdoor units. Please strictly follow the
requirements for welding process. Rosin joint or pin hole is not allowed.
(3) Radius of bending parts should be over 200mm. Note that pipes cannot be repeatedly bent or
stretched; otherwise the material will get harder. Do not bend or stretch the pipe for more than 3
times at the same position.
4.3.2 Flaring Process
(1) Use pipe cutter to cut the connection pipe in case it is unshaped.
(2) Keep the pipe downward in case cutting scraps get into the pipe. Clear away the burrs after
cutting.
(3) Remove the flared nut connecting indoor connection pipe and outdoor unit. Then use flaring
tool to fix the flared nut into the pipe (as shown in Fig.10).
(4) Check if the flared part is flaring evenly and if there is any crack.