PEX Installation Manual

23
IM-PF 724596 0416
10.3.2 Pressure Loss Table
Flow Rate
GPM
60°F (16°C) Water
Pressure Loss PSI/ 100 ft of Pipe
⅜ ½ ¾ 1 1¼ 1½ 2
0.5 2.0
0.75 4.1
1.0 7.0 1.6
Pressure Loss <1
PSI
1.5 14.9 3.4
2.0 25.4 5.8 1.1
2.5 38.5 8.7 1.6
3.0 53.9 12.2 2.3
3.5 16.2 3.0
4.0 20.8 3.9 1.1
4.5 25.8 4.8 1.4
5.0 31.4 5.9 1.7
6.0 44.0 8.2 2.4
7.0 10.9 3.2 1.2
8.0 14.0 4.1 1.6
9.0 17.4 5.1 1.9
10.0 21.1 6.2 2.3 1.0
11.0 25.2 7.4 2.8 1.2
12.0 29.6 8.8 3.3 1.5
13.0 34.3 10.1 3.8 1.7
14.0 11.6 4.4 2.0
15.0 13.2 5.0 2.2
16.0 14.9 5.6 2.5
17.0 16.7 6.3 2.8
18.0 18.5 7.0 3.1
19.0 20.5 7.7 3.4
20.0 22.5 8.5 3.8 1.0
25.0 12.8 5.7 1.5
30.0
Pressure Loss
Excessive as
Flow velocity
is > 12 ft/sec
18.0 8.0 2.2
35.0 10.7 2.9
40.0 13.7 3.7
45.0 17.0 4.6
50.0 5.6
55.0 6.6
60.0 7.8
65.0 9.0
70.0 10.4
75.0 11.8
NOTE: Pressure Loss based on Hazen-Williams Formula (C = 150)
Pressure Loss for Actual Length can be calculated by following formula:
Actual Length / 100 ft X Value from chart above
10.3.3 Velocity limits
Viega recommends the following design
velocities for hot and cold PEX water
distribution systems:
• Domestic cold water — 10 fps
• Domestic hot water — 8 fps
The ow velocity through Viega’s
PEX ttings does not fall under these
limitations. The equivalent length of PEX
tube for Viega PEX ttings is available
from Viega to assist in system sizing
where applicable. (Refer to Section “10.2
Viega PEX tting” on Page 21).