Rinnai 37AHB SERIES User Manual
Page 46

46
Rinnai Corporation Hydronic Furnace (37AHB) Manual
0
0
.1
0.
2
0
.3
0.
4
0
.5
0.
6
0
.7
0.
8
0
.9
1.
0
1700
1
666
1635
16
04
1576
154
3
1518
1492
1465
1430
1402
120
50.
3
49.
3
48.
4
47.
5
46.
6
45.
7
44.
9
44.
1
43.
3
42.
3
41.
5
130
61.
9
60.
7
59.
5
58.
4
57.
4
56.
2
55.
3
54.
3
53.
4
52.
1
51.
1
140
71.
7
70.
3
69.
0
67.
7
66.
5
65.
1
64.
0
62.
9
61.
8
60.
3
59.
1
150
82.
2
80.
5
79.
0
77.
5
76.
2
74.
6
73.
4
72.
1
70.
8
69.
1
67.
8
160
92.
1
90.
2
88.
6
86.
9
85.
4
83.
6
82.
2
80.
8
79.
3
77.
5
75.
9
1561
1
524
1490
14
56
1428
139
6
1364
1330
1230
1265
1224
120
48.
8
47.
7
46.
6
45.
6
44.
7
43.
7
42.
7
41.
6
38.
5
39.
6
38.
3
130
59.
1
57.
7
56.
4
55.
2
54.
1
52.
9
51.
7
50.
4
46.
6
47.
9
46.
4
140
68.
8
67.
2
65.
7
64.
2
63.
0
61.
6
60.
2
58.
7
54.
2
55.
8
54.
0
150
78.
7
76.
8
75.
1
73.
4
72.
0
70.
4
68.
8
67.
0
62.
0
63.
8
61.
7
160
88.
3
86.
2
84.
2
82.
3
80.
7
78.
9
77.
1
75.
2
69.
5
71.
5
69.
2
1391
1
350
1320
12
81
1245
120
9
1170
1131
1090
1064
1031
120
47.
9
46.
5
45.
5
44.
1
42.
9
41.
6
40.
3
39.
0
37.
5
36.
6
35.
5
130
58.
2
56.
5
55.
2
53.
6
52.
1
50.
6
49.
0
47.
3
45.
6
44.
5
43.
1
140
67.
5
65.
5
64.
1
62.
2
60.
4
58.
7
56.
8
54.
9
52.
9
51.
6
50.
0
150
77.
5
75.
3
73.
6
71.
4
69.
4
67.
4
65.
2
63.
1
60.
8
59.
3
57.
5
160
86.
8
84.
2
82.
3
79.
9
77.
6
75.
4
73.
0
70.
5
68.
0
66.
4
64.
3
1222
1
174
1140
11
00
1063
101
4
979
937
8
8
7
829
77
7
120
45.
9
44.
1
42.
8
41.
3
39.
9
38.
1
36.
8
35.
2
33.
3
31.
1
29.
2
130
55.
7
53.
5
52.
0
50.
2
48.
5
46.
2
44.
6
42.
7
40.
4
37.
8
35.
4
140
64.
1
61.
6
59.
8
57.
7
55.
7
53.
2
51.
3
49.
1
46.
5
43.
5
40.
7
150
72.
6
69.
7
67.
7
65.
3
63.
1
60.
2
58.
1
55.
6
52.
7
49.
2
46.
1
160
81.
5
78.
3
76.
1
73.
4
70.
9
67.
7
65.
3
62.
5
59.
2
55.
3
51.
8
O
pt
im
al
L
egs
@
50 C
F
M
/Leg
Ma
xi
m
um le
gs
@
40 C
F
M
/Leg
M
in
im
um
Legs
@
60 C
F
M
/Leg
O
pt
im
al
L
egs
@
50 C
F
M
/Leg
Ma
xi
m
um le
gs
@
40 C
F
M
/Leg
M
in
im
um
Legs
@
60 C
F
M
/Leg
O
pt
im
al
L
egs
@
50 C
F
M
/Leg
Ma
xi
m
um le
gs
@
40 C
F
M
/Leg
M
in
im
um
Legs
@
60 C
F
M
/Leg
O
pt
im
al
L
egs
@
50 C
F
M
/Leg
Ma
xi
m
um le
gs
@
40 C
F
M
/Leg
23
28
35
N
um
ber
of
3"
Di
am
et
er
B
ranc
h Legs
appl
ic
ab
le
t
o H
ig
h
V
el
oc
ity
S
ys
tem
s O
nl
y.
U
sed onl
y i
f m
et
hods
ot
her
than T
abl
e 3 i
s us
ed t
o det
er
m
ine duc
t s
iz
es
.
T
A
B
L
E
5
.1
4
: AI
R D
E
L
IV
E
R
Y
AN
D
P
E
RF
O
R
M
A
NC
E
D
A
T
A
(
B
O
T
T
O
M
O
R
S
ID
E
RE
T
URN
w
/
F
A
C
T
O
R
Y
S
U
P
P
L
IE
D
F
IL
T
E
R
)
UN
IT
SIZ
E
EC
M
SPE
E
D
TA
P
SU
PP
O
R
T
S
CO
O
L
IN
G
CAP
.
RANG
E
(T
O
N
S
)
A
H
B
75 +
R
75-
L
S
i(
e)
AI
RF
L
O
W
(CF
M
)
TAP
4
(L
)
2.
5
N
E
T
H
EAT
IN
G
C
A
PAC
IT
Y
(M
B
H
)
23
28
35
A
H
B
75 +
R
75-
L
S
i(
e)
AI
RF
L
O
W
(CF
M
)
TAP
3
(M
L)
3.
0
N
E
T
H
EAT
IN
G
C
A
PAC
IT
Y
(M
B
H
)
23
28
35
M
in
im
um
Legs
@
60 C
F
M
/Leg
A
H
B
75 +
R
75-
L
S
i(
e)
AI
RF
L
O
W
(CF
M
)
TAP
2
(M
H)
3.
5
N
E
T
H
EAT
IN
G
C
A
PAC
IT
Y
(M
B
H
)
23
28
35
37
AHB0
75
14
KA5 +
REU-VB2
52
8F
FUD(W
D)-
US
A
H
B
75 +
R
75-
L
S
i(
e)
AI
RF
L
O
W
(CF
M
)
TAP
1
(H)
4.
0
N
E
T
H
EAT
IN
G
C
A
PAC
IT
Y
(M
B
H
)
E
W
T (
O
F)
NO
M
INAL
HE
AT
IN
G
CA
P
ACI
T
Y
E
x
te
rn
a
l St
a
tic
Pr
e
ss
u
re
(
E
SP)
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
PECI
F
IC
E
SP)
/ 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
.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
TBD
See Note 6.
in. W.C.