21
iN401 - iN501 Air
Intake
Inlet
and
Exhaust
Gas
Outlet
Pipe
Connections
May
2019
-
Revision
00
7.3.2 Multiple Units Configurations
When more than one unit is installed, refer to “7.6 Intake Air
Inlet and Exhaust Gas Outlet Pipe Diameter and Length” on
page 24.
Connecting multiple units together requires proper sizing of
the air intake inlet and exhaust gas outlet pipes. Up to four
water heaters can be connected (cascaded) together. Units
which share a common vent must be connected together in
a cascading configuration, as described in “13. Connecting
Multiple Units” on page 48.
The following diagrams represent some typical direct venting
configurations and are included to assist in designing the
vent system. Possible configurations are not limited to the
following diagrams.
Intake
Air
Intake
Air
Intake
Air
Exhaust
Exhaust
Exhaust
7.3.3 Side Wall Air Intake Inlet and Exhaust Gas
Outlet Pipe Termination
1. Terminate the air intake inlet pipe with a 90° elbow
(angled down). Use a flange and PVC screen (not
supplied).
2. Terminate the exhaust gas outlet pipe on the exterior wall
at least 12” above ground and at least 18” away from the
air intake inlet pipe, or as required by local building codes.
In areas of high snow fall, protect the vent terminations
from blockage. Use a flange and PVC guard.
IQ-020
Intake Air
Exhaust
18” - 36” or over 72”
Single unit.
IQ-020a
Exhaust
Intake Air
See
Note A
Multiple units.
Note A:
The distance between any exhaust gas outlet and
air intake inlet pipe should be between 18 and 36
inches apart. If this minimum specification cannot
be met, the air intake inlet and exhaust gas outlet
pipes should be 72 inches apart or more.
3. To avoid moisture and frost build-up to openings on
adjacent homes, use 45° elbows, 90° elbows, or tees
for the vent termination to direct the exhaust gas fumes
away from the building.
