Rinnai 37AHB SERIES, Installation, Operation And Maintenance Manual

Page: 30 / 68

30
Rinnai Corporation Hydronic Furnace (37AHB) Manual
Air Distribution Guide
NOTES
:
1.
Calculations are based on airflo
w
of 50 CFM f
or ea
ch 3 inch diameter flexible leg.
2.
Calculations assume s
ystem is equipped
w
ith a st
andard ad
d-on
e
vaporative coil a
nd allow
s for
app
roximatel
y 120 e
quivalent l
ength of retur
n ducting.
3.
MAF – Ma
xi
mum airflow
(CFM).
4.
NOL –
Numbe
r o
f 3” diameter fle
xi
ble legs.
5.
If a more det
ailed duct sizing met
hod is required, r
efer to one
or mo
re of the
refer
enced documents or
an
y oth
er indust
ry
re
cognized standard.
LIST OF REFE
RENCES:
ACCA - Manu
al D (Residential D
uct Sy
stems)
ACCA - Fle
xible Duct Performa
nce & Installation Standards
ASHRAE Handb
ook-Fundam
enta
ls
HRAI - Residenti
al Air Sy
stem
De
sign Manual
SMACNA - HVA
C
S
ystem Duct D
esign Manual
MA
F
14
0
100
75
50
N
O
L
3221
MA
F
21
0
200
15
0
100
50
N
O
L
44321
MA
F
32
0
300
25
0
200
15
0
100
50
N
O
L
6654321
MA
F
42
0
40
0
35
0
30
0
25
0
20
0
15
0
10
0
N
O
L
88765432
MA
F
56
0
50
0
45
0
40
0
35
0
30
0
25
0
20
0
15
0
10
0
N
O
L
11
10
98765432
MA
F
90
0
850
80
0
750
70
0
650
60
0
550
50
0
450
40
0
350
30
0
250
200
150
N
O
L
18
17
16
15
14
13
12
11
10
9876543
MA
F
130
0
120
0
115
0
110
0
105
0
100
0
950
90
0
850
80
0
750
70
0
650
60
0
550
500
450
400
350
300
250
N
O
L
26
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
98765
MA
F
170
0
160
0
150
0
140
0
130
0
120
0
110
0
105
0
100
0
950
90
0
850
80
0
750
700
650
600
550
500
450
400
350
300
N
O
L
34
32
30
28
26
24
22
21
20
19
18
17
16
15
14
13
12
11
10
9876
MA
F
230
0
220
0
210
0
200
0
190
0
180
0
170
0
160
0
150
0
140
0
130
0
120
0
11
00
10
00
900
850
800
750
700
650
600
550
500
450
N
O
L
464
44
24
03
83
63
43
23
02
82
62
42
22
01
81
71
61
5
14
13
12
11
10
9
Ma
xi
mu
m
Ai
rf
lo
w
(C
FM
)
wit
h
Max
im
u
m
Nu
m
b
e
r
of
3"
fl
ex
le
g
s
Ma
xi
m
u
m
Eq
u
iv
al
e
n
t
Du
ct
Le
n
gt
h
(F
e
e
t)
Ta
b
le
3:
Qu
ic
k
Re
fe
re
n
ce
Hi
‐
Ve
lo
ci
ty
Du
ct
Si
zi
n
g
Ch
ar
t
Ri
gi
d
Tr
u
n
k
Du
ct
Di
am
e
te
r
(i
nc
he
s)
25
0
12
0
8
14
0
10
0
7
90
6
60
5 4
16
32
0
20
0
14
17
5
12 10