30
Outside Unit
Header branch method
L Below 150m(492ft)
Below H 50m(164ft)
l
Below 40m(131ft)
Below 15m(49ft)
Ú
Total refrigerant pipe length = A +a +b +c +d +e +f ≤ 300m(984ft)
1. When installing 1 outside unit indepen-
dently
Ex) 6 indoor units connected
Ⓐ
Outside unit
Ⓑ
Header branch
Ⓒ
Indoor unit
Ⓓ
Seal
• For the pipe length after the header branch (a~f), it is recommended to install the unit so that the difference of the pipe
distance connected to the indoor unit is minimized.
• The large difference in pipe distance can cause performance difference between indoor units.
• After the header branch, you cannot use the Y branch and header branch.
• When the pipe distance corresponding to the farthest indoor unit from the outside unit is 90m(295ft) or above, you must
change the main pipe diameter according to the outside unit capacity in accordance with the following table.
(This applies to both the liquid and gas pipes.)
Ú
Outside unit
Ⓐ
~ Header branch
part
Ⓑ
: Main pipe diameter (A)
Gas Pipe
Liquid Pipe
8, 10 HP .........................................................................Ø22.2(7/8)
’
Ø25.4(1)
8, 10 HP.........................................................................Ø9.52(3/8)
’
Ø12.7(1/2)
16, 20 HP .......................................................................Ø28.58(1-1/8)
’
Ø31.8(1-1/4)
16, 20 HP.......................................................................Ø12.7(1/2)
’
Ø15.88(5/8)
Refrigerant piping system
Outside unit
Liquid pipe
Gas pipe
capacity
[mm(inch)]
[mm(inch)]
8 HP
Ø9.52(3/8)
Ø22.2(7/8)
10 HP
Ø9.52(3/8)
Ø22.2(7/8)
16 HP
Ø12.7(1/2)
Ø28.58(1-1/8)
20 HP
Ø12.7(1/2)
Ø28.58(1-1/8)
Longest pipe length (Equivalent pipe length)
A +f ≤ 150m(492ft)( 175m(574ft))
Longest pipe length after 1st branching
f ≤ 40m(131ft)
High/Low difference (Outside unit
÷
Indoor unit)
H ≤ 50m(164ft)
High/Low difference (Indoor unit
÷
Indoor unit)
h ≤ 15m(49ft)
L
ℓ
H
h