128
10.2 Allowable pipe length and drop height among indoor and outdoor units
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).
L1
L2
L11
L3
L4
Module 3
Module 2
Module 1
L10: 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).
R410A Refrigerant System
Allowable Value
m(ft.)
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(ft.)
Actual length
≤
165(541-1/4)
L
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)
≤
90(295-1/4)
——
Outdoor unit at lower(2)
≤
90(295-1/4)
——
Height difference between indoor units
≤
30(98-2/4)
h1
Maximum length of Main pipe(3)
＜
90(295-1/4)
L1
From IDU to its nearest branch (4)
≤
40(131-1/4)
A11,A12,B21,B22,D21,D22
NOTES:
(1) Normally, the pipe length from the first branch of IDU to the farthest IDU is 40m(131-1/4feet).
