Installation Guide

24 Rinnai Tankless Water Heater Installation and Operation Manual
• The vent piece connected to the water
heater must be secured with 1 self-tapping
screw.
• Refer to the instructions of the vent system
manufacturer for component assembly
instructions.
• If the vent system is to be enclosed, it is
suggested that the design of the enclosure
shall permit inspection of the vent system.
The design of such enclosure shall be
deemed acceptable by the trained and
qualified professional or the local
inspector.
• Any issues resulting from improper vent
installation will not be covered by warranty.
• When an existing Category I appliance is
replaced by this tankless water heater, the
original venting system may not be
suitable for Category IV appliance.
Approved vent materials must be used.
• For common vent installation with 3 or
more units, refer to common vent
installation instructions.
• Internal water heaters can be installed as
direct vent or non-direct vent applications.
• When installed as Direct Vent, refer to the
“Direct Vent Approved Vent Manufacturers
and Products” section (within section “4.5.4
1. Direct Vent”) for a complete list of
approved vent manufacturers and products.
• When installed as Non-Direct Vent (Room
Air), the vent must be Category IV, listed by
a national recognized testing agency or
solid core schedule 40 PVC when accepted
by local codes.
• When installed as Non-Direct Vent
(outdoor), the Rinnai specified outdoor vent
cap must be used.
• Exhaust must be directly vented to the
outside. Intake air can be provided from
outside (Direct Vent) or from room air (Non-
Direct Vent).
• If using room air (non-direct vent) for
combustion, ensure the required volume of
indoor air is available in accordance with
one of the following:
A. The National Fuel Gas Code, ANSI
Z223.1/NFPA 54;
B. CSA B149.1, Natural Gas and Propane
Installation Code; or
C. Applicable provisions of the local
building code.
• Avoid dips or sags in horizontal vent runs
by installing supports per the vent
manufacturer’s instructions.
• Support horizontal vent runs every 4 ft (1.2
m) and all vertical vent runs every 6 ft (1.83
m) or as per vent manufacturer’s
instructions or local code requirements.
• Venting should be as direct as possible with
a minimum number of pipe fittings.
• For manufactured vent systems, vent
connections must be firmly pressed
together so that the connections form an air
tight seal. Follow the venting
manufacturer’s instructions.
• Refer to the PVC/CPVC manufacturer for
appropriate fittings, solvents or joining
methods.
• DO NOT use cellular core PVC/CPVC.
• DO NOT use Radel®
(polyphenylsulfone) or galvanized
material to vent this appliance.
• DO NOT cover non-metallic vent pipe
and fittings with thermal insulation.
• DO NOT combine vent components
from different manufacturers.
• You can reduce the vent diameter from
3 to 2 inch. Vent diameter cannot be
less than 2 in. (51 mm).
• DO NOT connect the venting system
with an existing vent or chimney.
• DO NOT common vent with the vent
pipe of any other manufacturer’s water
heater or appliance.
• Rinnai water heaters can only be
common vented with Schedule 40
PVC/CPVC or with a Rinnai certified
common vent system.
WARNING
IMPORTANT
If reusing existing venting, the venting should
be inspected for damage and to ensure it is
appropriate (approved) for this water heater.
To ensure safe and proper operation,
damaged vent components MUST be
replaced before operating the water heater.