Navien NR-180A, Operation & Installation Manual

Page: 52 / 89

INSTALLATION
52
6. Cascade system Plumbing Pipe Size (@ NR/NP-240(A))
Q’ty
1 7.19 4.78 20A 3/4” 16 115.07 5.44 80A 3”
2 14.38 5.61 25A 1” 17 122.26 5.81 80A 3”
3 21.57 5.54 30A 11/4” 18 129.45 6.14 80A 3”
4 28.77 5.21 40A 11/2” 19 136.64 6.46 80A 3”
5 35.96 6.53 40A 11/2” 20 143.83 6.83 80A 3”
6 43.15 4.49 50A 2” 21 151.02 4.06 100A 4”
7 50.34 5.24 50A 2” 22 158.21 4.25 100A 4”
8 57.5 6.00 50A 2” 23 165.41 4.45 100A 4”
9 64.72 4.39 65A 21/2” 24 172.60 4.65 100A 4”
10 71.92 4.75 65A 21/2” 25 179.79 4.85 100A 4”
11 79.11 5.34 65A 21/2” 26 186.98 5.05 100A 4”
12 86.30 5.84 65A 21/2” 27 194.17 5.24 100A 4”
13 93.49 6.33 65A 21/2” 28 201.36 5.44 100A 4”
14 100.68 6.79 65A 21/2” 29 208.56 5.61 100A 4”
15 107.87 5.11 80A 3” 30 215.75 5.81 100A 4”
T=86 ºF
Flowrate
(GPM)
Velocity
of Water
(ft/s)
Pipe
Diameter
(mm/in)
Q’ty
T=86 ºF
Flowrate
(GPM)
Velocity
of Water
(ft/s)
Pipe
Diameter
(mm/in)
ú
If the flow rate inside pipes is over 6.6 ft/s, erosion might be occur inside
the pipes.
ú
Above spec’s may be different depending on installation circumstance.