34
Outdoor Unit
Refrigerant piping installation
Longest piping length
**Equivalent piping length
A+B+C+D+e
≤
120m
A+B+C+D+e
≤
140m
Longest piping length after 1st branch
B+C+D+e
≤
30m
Difference in height(Outdoor Unit
↔
Indoor Unit)
H
≤
50m ( 40m : Outdoor Unit is lower than Indoor Units)
Difference in height (Indoor Unit
↔
Indoor Unit)
h
≤
15m
*L
l
H
h
➲
Refrigerant pipe diameter from branch to branch (B,C,D)
➲
Total piping length = A+B+C+D+a+b+c+d+e
≤
220m
Downward Indoor Unit total capacity
[kW(Btu/h)]
~8.3(28,300)
Ø9.52(3/8 inch)
Ø15.88(5/8 inch)
~17.8(60,700)
Ø12.7(1/2 inch)
Ø19.05(3/4 inch)
~27.9(95,200)
Ø12.7(1/2 inch)
Ø25.4(1 inch)
~42.4(144,700)
Ø12.7(1/2 inch)
Ø28.58(1
1
/
8
inch)
~58.5(199,600)
Ø15.88(5/8 inch)
Ø31.8(1
1
/
4
inch)
~75.4(257,300)
Ø19.05(3/4 inch)
Ø38.1(1
1
/
2
inch)
75.5(257,600)~
Ø22.2(
7
/
8
inch)
Ø44.5(1
3
/
4
inch)
Liquid pipe
(mm)
Gas pipe
(mm)
WARNING
Install the same main pipe diameter as those connected after the initial branch where the pipe
diameter connected after the initial branch.
Ex) Where connecting the Indoor Unit to 24HP (67.2kW) to the 120%.
Main pipe diameter of Outdoor Unit: Ø 38.1 (Gas pipe) Ø 19.05(Liquid pipe)
Main pipe diameter of Outdoor Unit: Ø 44.5 (Gas pipe) Ø 22.2 (Liquid pipe) depending on 120% Indoor Unit
combination
Therefore, Ø 44.5 (Gas pipe), Ø 22.2 (Liquid pipe) as pipe diameter of the large side is selected as main
pipe diameter.
*: Must be satisfied both conditions
**: Assume equivalent pipe length of Y branch to be 0.5m, that of header to be 1m, calculation purpose.
• Piping length from outdoor branch to outdoor unit
≤
10m, equivalent lengh : max 13m
(for 16HP or more)