Burnham Apex APX399 Installation, Operating And Service Instructions page 20

iV. Venting
B. CPVC/PVC Venting (continued)
Table 6: Vent System and Combustion Air System Components Equivalent Length
vs. Component nominal Diameter
Vent or Combustion air System
Component Description
Component nominal Diameter, in.
90° Elbow (Sch. 80 or Sch.40)
45° Elbow (Sch. 80 or Sch. 40)
Sch. 40 CPVC Pipe x 30 In. Long
Sch. 40 PVC Pipe x 1 Ft. Long
Sch. 40 PVC Pipe x 2 Ft. Long
Sch. 40 PVC Pipe x 3 Ft. Long
Sch. 40 PVC Pipe x 4 Ft. Long
Sch. 40 PVC Pipe x 5 Ft. Long
Table 7: Expansion Loop Lengths
nominal Length of
Pipe Straight run
Dia. (in.) (Ft.)
20
30
4 40
50
60
20
30
6 40
50
60
apply supplied dielectric grease to gasket inside vent section of two-pipe vent connector. Failure to apply the
grease could result in gasket rupture during vent pipe installation and gasket deterioration due to condensate
exposure.
20
Equivalent Length (Ft.) for Vent or Combustion Air System Component
CHANGE OF DIRECTION
(VERTICAL OR HORIZONTAL)
LONG RUN OF PIPE
KEY
RESTRAINT (RESTRICTS MOVEMENT)
HANGER (ALLOWS MOVEMENT)
Loop Length
"L" (in.)
60
74
85
95
104
73
90
103
116
127
vs. Component nominal Diameter (in.)
4"
13
4.5
L
(HORIZONTAL ONLY)
6"
MIN
Figure 5: Expansion Loop and Offset
Warning
6"
22
7.5
2.5
1
2
3
4
5
L
4
(L)
LOOP LENGTH
LOOP
(TOP VIEW)
L
2 L
6"
L
MIN
5
OFFSET
L
2
L
4
5