Rinnai 37AHB SERIES - Manual (Page 50)

50 Rinnai Corporation Hydronic Furnace (37AHB) Manual
N
O
T
E
S
:
1.
E
W
T
- En
teri
ng
W
ater Tempe
ratur
e (F)
.
2.
CFM - Air
flow
in (C
ubic Feet per
Minute).
3.
Legs - 3
in
ch
diame
ter
flex
ible du
cts to
diffu
ser
s.
4.
1 MBH =
1000
BTU/H.
5.
Shaded b
ox
represents ra
ting
poin
t; re
fer
to
w
iring diagra
m
for
factory
se
t sp
eed
taps.
6.
Number of 3”
diam
eter
leg
s
spe
cifi
ed i
n ta
ble a
bov
e is
fo
r
rating
poin
t o
nly
(i.e
. a
t Ex
ternal S
ta
tic
Pres
sure
of
0
.5
in. w
c. and
speed
TAP3, TAP1, TAP2
, TAP2
for
AHB45
, AH
B60, AHB75, A
H
B90 re
spe
ctiv
ely
). Final
leg
count i
s
to b
e de
termined
b
y the in
stalli
ng
con
tractor
and i
s to
be
based
on
the
follow
ing formula:
NUMBER OF LEG
S
= TOTAL
AVA
IL
ABLE CFM
(A
T THE S
P
ECI
F
IC
E
S
P)
/ DESI
RED CFM per LEG
(40, 50, or 60 CF
M)
Ex
ample: Giv
en the
design
point
for
A
H
B045 o
f 0
.8
ESP
, Low
fan
speed
(Ta
p5). From
tabl
e 5
.0
, av
ailable CFM i
s
569 and
the d
esir
ed CFM per
leg
is 50
CFM.
Therefore,
Number of Leg
s =
569/50
= 11
.38
rou
nded dow
n to
11
.
0
0
.1
0.
2
0
.3
0.
4
0
.5
0.
6
0
.7
0.
8
0
.9
1.
0
948
921
891
868
8
4
1
8
1
9
795
772
701
596
567
120
29.
3
29.
3
29
.3
29
.3
29.
3
29.
3
29.
3
29.
3
29.
3
29
.3
29
.3
130
39.
4
38.
3
37
.1
36
.1
35
34.
1
33.
1
32.
1
29.
2
24
.8
23
.6
140
47.
4
46
44
.5
43
.4
42
40.
9
39.
7
38.
6
35.
0
29
.8
28
.3
150
54.
7
53.
1
51
.4
50
.1
48.
5
47.
3
45.
9
44.
5
40.
4
34
.4
32
.7
160
63.
3
61.
5
59
.5
57
.9
56.
1
54.
7
53.
1
51.
5
46.
8
39
.8
37
.8
921
891
864
836
8
1
2
7
8
8
768
742
699
594
559
120
34.
6
33.
4
32
.4
31
.4
30.
5
29.
6
28.
8
27.
9
26.
2
22
.3
21
.0
130
40.
4
39.
1
37
.9
36
.7
35.
6
34.
6
33.
7
32.
6
30.
7
26
.1
24
.5
140
47.
7
46.
1
44
.7
43
.3
42.
0
40.
8
39.
8
38.
4
36.
2
30
.8
28
.9
150
54.
0
52.
2
50
.7
49
.0
47.
6
46.
2
45.
0
43.
5
41.
0
34
.8
32
.8
160
62.
8
60.
8
58
.9
57
.0
55.
4
53.
7
52.
4
50.
6
47.
7
40
.5
38
.1
803
768
740
712
6
8
2
6
5
2
628
596
569
541
510
120
32.
3
30.
9
29
.8
28
.6
27.
4
26.
2
25.
3
24.
0
22.
9
21
.8
20
.5
130
38.
5
36.
8
35
.4
34
.1
32.
7
31.
2
30.
1
28.
5
27.
2
25
.9
24
.4
140
45.
4
43.
4
41
.8
40
.2
38.
5
36.
8
35.
5
33.
7
32.
2
30
.6
28
.8
150
53.
5
51.
2
49
.3
47
.4
45.
4
43.
4
41.
8
39.
7
37.
9
36
.0
34
.0
160
60.
8
58.
1
56
.0
53
.9
51.
6
49.
4
47.
5
45.
1
43.
1
40
.9
38
.6
20
T
A
B
L
E 5
.1
8
: A
IR
D
E
L
IVER
Y A
N
D
PE
R
F
O
R
M
A
N
C
E D
A
T
A
(
B
O
T
T
O
M
O
R
S
ID
E
R
E
T
U
R
N
w
/ F
A
C
T
O
R
Y
SU
PPL
IE
D
F
IL
T
ER
)
UNI
T
SI
Z
E
EC
M
S
PEE
D
TA
P
SUP
P
ORT
S
C
OOL
IN
G C
A
P
.
RA
NG
E (
T
O
N
S)
EW
T
(
O
F)
NO
M
INA
L
HEA
T
IN
G
CA
P
A
CI
TY
Ex
te
rn
a
l
St
a
ti
c
Pr
es
sur
e
(
E
S
P
) i
n
. W
.C
.
TB
D
See
N
ot
e 6.
TB
D
S
ee N
ot
e 6.
37 AH B045 08KA5 + RE U-V A3237F FU (W )-US /A SM E
A
H
B4
5
+
R9
8
L
S
i(
e
)/
A
S
M
E
A
IRFLOW
(
C
FM
)
TA
P
3
(H
)
2.
0
NE
T
HE
A
TI
N
G
CAP
A
CI
TY
(M
B
H
)
13
16
TB
D
S
ee N
ot
e 6.
TB
D
See
N
ot
e 6.
TB
D
S
ee N
ot
e 6.
M
ini
m
um
Legs
@
60 C
F
M
/Leg
A
H
B4
5
+
R9
8
L
S
i(
e
)/
A
S
M
E
A
IRFLOW
(
C
FM
)
TA
P
4
(M
)
2.
0
NE
T
HE
A
TI
N
G
CAP
A
CI
TY
(M
B
H
)
TB
D
S
ee N
ot
e 6.
A
H
B4
5
+
R9
8
L
S
i(
e
)/
A
S
M
E
A
IRFLOW
(
C
FM
)
TA
P
5
(L
)
1.
5
NE
T
HE
A
TI
N
G
CAP
A
CI
TY
(M
B
H
)
M
ini
m
um
Legs
@
60 C
F
M
/Leg
O
pt
im
al
Legs
@
50
C
F
M
/L
eg
M
ax
im
um
Legs @
40 C
F
M
/Leg
M
ini
m
um
Legs
@
60 C
F
M
/Leg
O
pt
im
al
Legs
@
50
C
F
M
/L
eg
M
ax
im
um
Legs @
40 C
F
M
/Leg
O
pt
im
al
Legs
@
50
C
F
M
/L
eg
M
ax
im
um
Legs @
40 C
F
M
/Leg
N
um
ber
of
3"
di
am
et
er
br
an
ch
le
gs
appl
ic
abl
e t
o
H
ig
h
V
el
oc
ity
S
yst
em
s on
ly
.
U
ded o
nl
y i
f
m
et
hods ot
her
th
an
Tabl
e
3 i
s used t
o
det
er
m
ine du
ct
s
izes
.