100304526_2000545240 _Rev. 01
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35
WATER
HEATER
MODEL
HEATER
INPUT
(BTU/HR)
VENT SIZE (INSIDE
DIAM.)
PRESSURE
SWITCH
SETTINGS
(in. W.C.)
2 PIPE
EQUIV. VENT LENGTH
CONC. VENT
EQUIV. VENT LENGTH
N.C.
N.O.
MAX.
MIN.
MAX.
MIN.
40 gal.
40k
2”
(See Figure 47)†
-2
-0.75
50’ plus term.
elbow and
debris screen*
7’ plus term. elbow
and restrictive
screen* on both
intake and exhaust
45’ plus term.
and debris
screen*
7’ plus
term. and
restrictive
screen* on
exhaust only
50 gal.
45k
40 gal.
40k
3”
(See Figure 48)
-2
-0.75
125’ plus
term. elbow
and restrictive
screen*
7’ plus term. elbow
and restrictive
screen* on both
intake and exhaust
100’ plus
term. and
restrictive
screen*
7’ plus
term. and
restrictive
screen* on
exhaust only
50 gal.
45k
62k (N.G.)
3”
(See Figure 48)
-1.75
-0.5
50’ term. elbow
and debris
screen*
45’ plus term.
and debris
screen*
58k (L.P.)
75 gal.
76k
-1.5
-1.05
40 gal.
40k
4”
(See Figure 49)
-2
-0.75
180’ plus term.
elbow and
debris screen*
50’ plus term.
elbow and debris
screen*
n/a
n/a
50 gal
45k
50 gal.
58k (L.P.)
4”
(See Figure 49)
-1.75
-0.5
125’ plus term.
elbow and
debris screen*
62k (N.G.)
75 gal.
76k
-1.5
-1.05
* see Figure 41 and Table 5.
† Requires 2” kit 100086430.
Notes:
1. A horizontal vent
must
have a 45° or 90° vent termination elbow to direct the vent pipe downward unless
otherwise specified by local requirements.
2. A vertical vent
must
have a 90° elbow to direct the vent pipe horizontally followed by a vent termination 45°
elbow to direct the vent pipe downward unless otherwise specified by local requirements.
3. If additional elbows are used in the vent system the allowable vent lengths are reduced.
4. Two 45° elbows are considered the equivalent of one 90° elbow.
Table 6.
WATER
HEATER
MODEL
HEATER
INPUT
(BTU/
HR)
VENT
SIZE
(INSIDE
DIAM.)
PRESSURE
SWITCH
SETTINGS
(in. W.C.)
LOW PROFILE
EQUIV. VENT
LENGTH
PYRAMID
EQUIV. VENT LENGTH
MUSHROOM
EQUIV. VENT LENGTH
N.C.
N.O.
MAX.
MIN.
MAX.
MIN.
MAX.
MIN.
40 gal.
40k
3” (See
Figure 48)
-2
-0.75
75’ plus
term. and
restrictive
screen*
on both
intake and
exhaust
7’ plus
term. and
restrictive
screen*
on both
intake
and
exhaust
50’ plus
term. and
restrictive
screen*
7’ plus term.
and restrictive
screen* on
both intake and
exhaust
50’ plus
term. and
restrictive
screen*
7’ plus term.
and restrictive
screen* on
both intake
and exhaust
50 gal.
45k
62k
(N.G.)
-1.75
-0.5
50’ plus
term.
50’ plus
term.
7’ term. and
restrictive
screen* on
both intake and
exhaust
50’ plus
term.
7’ plus term.
and restrictive
screen* on
both intake
and exhaust
58k (L.P.)
75 gal.
76k
-1.5
-1.05
* see Figure 41 and Table 5.
Notes:
1. A horizontal vent
must
have a 45° or 90° vent termination elbow to direct the vent pipe downward unless
otherwise specified by local requirements.
2. A vertical vent
must
have a 90° elbow to direct the vent pipe horizontally followed by a vent termination 45°
elbow to direct the vent pipe downward unless otherwise specified by local requirements.
3. If additional elbows are used in the vent system the allowable vent lengths are reduced.
4. Two 45° elbows are considered the equivalent of one 90° elbow.
Table 7.
