Rinnai 37AHB SERIES - Manual (Page 53)

Rinnai Corporation Hydronic Furnace (37AHB) Manual 53
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
31.
4
30.
5
29
.5
28
.7
27.
8
27.
1
26.
3
25.
6
23.
2
19
.7
18
.8
130
37.
4
36.
3
35
.2
34
.3
33.
2
32.
3
31.
4
30.
5
27.
7
23
.5
22
.4
140
46
44
.7
43
.2
42
.1
40.
8
39.
7
38.
6
37.
4
34.
0
28
.9
27
.5
150
52.
3
50.
8
49
.1
47
.9
46.
4
45.
2
43.
9
42.
6
38.
7
32
.9
31
.3
160
59.
3
57.
6
55
.7
54
.3
52.
6
51.
2
49.
7
48.
3
43.
8
37
.3
35
.5
921
891
864
836
8
1
2
7
8
8
768
742
699
594
559
120
31.
8
30.
8
29
.9
28
.9
28.
1
27.
2
26.
5
25.
6
24.
2
20
.5
19
.3
130
37.
2
36.
0
34
.9
33
.8
32.
8
31.
8
31.
0
30.
0
28.
2
24
.0
22
.6
140
45.
8
44.
3
42
.9
41
.6
40.
4
39.
2
38.
2
36.
9
34.
7
29
.5
27
.8
150
52.
1
50.
4
48
.9
47
.3
45.
9
44.
6
43.
4
42.
0
39.
5
33
.6
31
.6
160
58.
7
56.
7
55
.0
53
.2
51.
7
50.
2
48.
9
47.
3
44.
5
37
.8
35
.6
803
768
740
712
6
8
2
6
5
2
628
596
569
541
510
120
31.
2
29.
8
28
.7
27
.7
26.
5
25.
3
24.
4
23.
2
22.
1
21
.0
19
.8
130
35.
3
33.
8
32
.6
31
.3
30.
0
28.
7
27.
6
26.
2
25.
0
23
.8
22
.5
140
41.
1
39.
3
37
.8
36
.4
34.
9
33.
3
32.
1
30.
5
29.
1
27
.7
26
.1
150
49.
0
46.
8
45
.1
43
.4
41.
6
39.
7
38.
3
36.
3
34.
7
33
.0
31
.1
160
55.
0
52.
6
50
.7
48
.7
46.
7
44.
6
43.
0
40.
8
38.
9
37
.0
34
.9
TB
D
S
ee N
ot
e 6.
37AHB 04508K A5 + RE U-V AM 16 20W
AH
B
4
5
+
V
5
3
e
A
IRFLOW
(
C
FM
)
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
TA
P
5
(L
)
1.
5
NE
T
HE
A
TI
N
G
CAP
A
CI
TY
(M
B
H
)
TB
D
S
ee N
ot
e 6.
TB
D
See
N
ot
e 6.
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.
TB
D
See
N
ot
e 6.
TB
D
S
ee N
ot
e 6.
20
AH
B
4
5
+
V
5
3
e
A
IRFLOW
(
C
FM
)
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
AH
B
4
5
+
V
5
3
e
A
IRFLOW
(
C
FM
)
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
TA
P
3
(H
)
2.
0
NE
T
HE
A
TI
N
G
CAP
A
CI
TY
(M
B
H
)
13
16
T
A
B
L
E 5
.2
1
: 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
.
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
.