Venting Guidelines - Rinnai RU98i Installation Manual

Venting Guidelines

WARNING
DO NOT

Do not install in separate distribution systems. All
water heaters common vented must be in the
same hot and cold plumbing manifolds and must
not exceed 8 units.

Do not use PVC, CPVC, ABS or galvanized material
for the exhaust vent.
exhaust.

Do not combine vent components from different
manufacturers.

Vent diameter must not be reduced.

Do not connect the venting system with an
existing vent or chimney.

Do not common vent with the vent pipe of any
other type of water heater or appliance.

Do not install the water heater in an area of
negative pressure.

Do not install the water heater, venting, and vent
termination(s) in any areas where the air may
contain corrosive compounds.
MUST DO
•
The water heater dip switch setting must always
be set to long vent (#1 in set of tan switches set to
OFF).

This water heater is a direct vent water heater and
therefore is certified and listed with the vent
system. You must use vent components that are
certified and listed with the water heater model.

The vent system must vent directly to the outside
of the building and use outside air for combustion.

Avoid dips or sags in horizontal vent runs by
installing supports per the vent manufacturer's
instructions.
The Ubbink Polypropylene CVent can be used on both the combustion air and exhaust.
Field supplied PVC material can only be used on the combustion air side and MUST NOT
be used for the exhaust.
CVent must be used on the

Support horizontal vent runs a minimum of every
four feet and all vertical vent runs a minimum of
every six feet.

Venting should be as direct as possible with a
minimum number of pipe fittings.

Vent connections must be firmly pressed together
so that the gaskets form an air tight seal.

Install an appliance adapter which contains a
check valve onto each water heater. Use only the
check valve specified in this manual. Do not
attempt to build your own system.

The air intake appliance adapter connected to the
water heater must be secured with one self-
tapping screw.

Check and clean the header check valve every 12
months according to the maintenance instructions
in this manual.

Set the temperature setting on all water heaters
being common vented to the same temperature.
INFORMATION

Unless recovering a tank, Rinnai recommends
installing an MSB controller when common
venting and where water heaters are in a manifold
system.

For assembly details, refer to the Ubbink
Installation and Assembly Instructions located in
the appendix of this manual.

Rinnai recommends replacing the check valve
when replacing the water heater.
11 Rinnai CVent