Use U-shaped branch joints as specified on the
construction drawings – do not replace U-shaped branch
joints with tee joints.
To avoid accumulation of oil in the outdoor units, outdoor
branch joints should be installed horizontally and must not
be higher than the outdoor unit refrigerant outlets. Refer
to Figure 3-5.9.
Indoor branch joints may be installed either horizontally or
vertically. Horizontal branch joints must be installed at an
angle to the horizontal not exceeding 10° in order to avoid
uneven distribution of refrigerant and possible
malfunction. Refer to Figure 3-5.8.
To ensure even distribution of refrigerant, a limitation is placed on how close branch joints may be installed to
bends, other branch joints and the straight sections of piping leading to indoor units. Refer to Part 3, 4.6 “Branch
Joints”.