A.O. Smith ProMax GPDX-50, Instruction Manual

Page: 17 / 36

17
VENT CONNECTIONS TO BLOWER ASSEMBLY
Figure 15 shows the typical vent connections.
FIGURE 15.
VENTING AND INSTALLATION
Plan the layout of the vent system from the vent termination to the water
heater considering all of the 90° and 45° elbows plus the number of
feet of pipe that would be needed to install the total vent system. Note:
The inlet connection to the blower requires a minimum 3" long x 3"
Schedule 40 PVC pipe. The water heater must be vented to the
outdoors as described in these instructions. DO NOT connect this water
heater to an existing vent or chimney. It must be vented separately
from all other appliances. The
fi ttings, other than the supplied Vent
Termination should be equivalent to the following: PVC (Schedule 40,
DWV, ASTM D-2665), CPVC (Schedule 40, DWV, ASTM F-438), ABS
(Schedule 40 DWV, ASTM D-2661).
The cement used should be as recommended by the vent
pipe manufacturer. See the instructions in the “VENT PIPE
PREPARATION” section of this manual for the proper method of
cutting and cementing the PVC pipe and
fi ttings.
All vent gases must be completely vented to the outdoors of the
structure (dwelling). When determining the installation location for
a power direct vent water heater, snow accumulation and drifting
should be considered in areas where applicable.
IMPORTANT: DO NOT common vent this water heater with any
other appliance.
FIGURE 16.
Horizontal runs must be securely supported at 3 1/2 foot (1 m)
intervals and vertical runs supported at 5 foot (1.5 m) intervals.
FIGURE 17.
VENTING THROUGH AN OUTSIDE WALL
A. All 75 Gallon Models
In the carton is supplied:
1. Two 3” inlet and outlet PVC Schedule 40 - 45° vent caps.
2. One 3” CPVC Schedule 80 - 90° elbow; used to connect the outlet
vent pipe to the water heater when the outlet vent pipe is to be
turned horizontally directly off the blower.
3. One 5’ (1.5 m) section of 3” CPVC Schedule 40 outlet vent pipe.
(More may be required and must be purchased locally.)
Note: A 2-5/8" (66.675 mm) long section of CPVC pipe can be cut
from the 5' (1.5 m) section of 3" CPVC Schedule 40 vent pipe.
This is used to connect the
outlet vent pipe elbow to the water
heater when the outlet vent pipe is to be turned horizontally
directly off the blower.
FIGURE 18.
Requirements:
1. The water heater requires its own (separate) venting system.
2.
Only 3” CPVC Schedule 40 piping and fi ttings are acceptable
materials on the fi rst fi ve feet of the outlet vent system.
3. 3” PVC, ABS, or CPVC Schedule 40 piping and fi ttings are
acceptable materials for the inlet vent system and for the outlet
vent system after the fi rst fi ve feet.