Installation, Notice – Rinnai 37AHB SERIES User Manual
Page 12
12
Rinnai Corporation Hydronic Furnace (37AHB) Manual
Fitting or Valve
3/8"
1/2"
3/4"
1"
1 1/4"
1 1/2"
2"
2 1/2"
3"
90 deg. Elbow
0.5
1
2
2.5
3
4
5.5
7
9
45
deg.
elbow
0.35
0.5
0.75 1 1.2 1.5 2 2.5 3.5
Straight thru tee
0.2
0.3
0.4
0.45
0.6 0.8 1 0.5 1
Side port tee
2.5
2
3
4.5
5.5
7
9
12
15
Reducer
coupling 0.2 0.4 0.5 0.6 0.8 1 1.3 1 1.5
Gate
valve
0.35 0.2 0.25 0.3 0.4 0.5 0.7 1 1.5
Globe
valve
8.5 15 20 25 36 46 56 104
130
Angle
valve
1.8 3.1 4.7 5.3 7.8 9.4 12.5 23 29
Ball
valve
1.8 1.9 2.2 4.3 7 6.6 14 0.5 1
Swing check valve
0.95
2
3
4.5
5.5
6.5
9
11
13
Flow check valve
NA
NA
83
54
74
57
177
85
98
Butterfly
valve
NA 1.1 2 2.7 2 2.7 4.5 10
15.5
Rinnai Flow Sensor
NA
NA
3.2 NA NA NA NA NA NA
Taco
49-075
Air
NA NA 0.3 NA NA NA NA NA NA
Table 2: Equivalent Length of Straight Pipe for Valves and Fittings (ft)
Rinnai Flow Sensor
ball valves
TACO Model 49-075
Air Separator
gauge
cap
3/4 in. type M copper tubing
4 ft
9 ft
15 ft
5 ft
10 ft
3 ft
3 ft
3 ft
3 ft
3 ft
3 ft
12 ft
10 ft
FS
PROCEDURE FOR CALCULATING THE TOTAL
EQUIVALENT LENGTH OF PIPE
Given piping assembly as shown in Figure 10 below,
what is the total equivalent length of the system?
First determine the total straight pipe lengths; next
refer to table 2 to determine the equivalent straight
pipe length for each fitting shown. Add together the
equivalent lengths of piping and fittings.
Installation
Where possible the length of pipe
should not exceed 150 feet total
equivalent length.
Any piping running through
unconditioned space MUST be
insulated to prevent heat loss,
and possible freezing of the line.
Stickers indicating direction of
flow, (WATER IN, and WATER
OUT) are labeled on the outside
of the cabinet. DO NOT reverse
these lines, as this will cause the
unit to malfunction.
NOTICE
¾” Tubing (total straight pipe length)....68 ft.
(6) ¾” 90 deg. Elbows….……..6(2) = 12 ft.
(2) ¾” Side port tee……….…..2(3) = 6.0 ft.
(1) ¾” Taco air separator….1(0.3) = 0.3 ft.
(1) ¾” Rinnai flow sensor.....1(3.2) = 3.2 ft.
(2) ¾” Ball valves….….….....2(2.2) = 4.4 ft.
Total Equivalent length……..……93.9 ft.
Figure 10
Equivalent Length Calculation