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

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Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial INSTALLATION
42
3 ALLOWABLE PIPE LENGTH AND DROP HEIGHT AMONG IDU AND
ODU
Y type branch joint is adopted to connected indoor and outdoor units. Connecting method is shown
in the figure below.
Remark: Equivalent length of one Y-type manifold is about 0.5m(1-3/4feet).
L12: Length from the first branch to the farthest IDU; L11: Length from the first branch to the nearest
IDU; Equivalent length of branch of IDU is 0.5m (1-3/4feet).
Equivalent length of mode exchanger depends on the using situation, for example, when using one
branch, the length is 1m (39-3/8 inch), when using N branches, the length is N meters.
R410A Refrigerant System
Allowable Value
m(feet)
Fitting Pipe
Total length (actual length) of fitting pipe
≤1000(3280-3/4) L1+L2+L3+L4+…+L10+A11+A12+…+D21+D22
Length of farthest
fitting pipe m(feet)
Actual length
≤165(541-1/4)
L1+L7+L8+L10+D22
Equivalent length
≤190(623-1/4)
Difference between the pipe length from the first
branch of IDU to the farthest IDU and the pipe
length from the first branch of IDU to the nearest
IDU
≤40(131-1/4)
L12-L11
Equivalent length from the first branch to the
furthest piping (1)
≤40(131-1/4)
L7+L8+L10+D22
Height difference
between outdoor unit
and indoor unit
Outdoor unit at upper(2)
≤50(164) ——
Outdoor unit at lower(2)
≤40(131-1/4) ——
Height difference between indoor units
≤15(49) ——