10
VENTING

WARNING

THE INSTRUCTIONS IN THIS SECTION ON VENTING MUST
BE FOLLOWED TO AVOID CHOKED COMBUSTION OR
RECIRCULATION OF FLUE GASES. SUCH CONDITIONS
CAUSE SOOTING OR RISKS OF FIRE AND ASPHYXIATION.
Heater must be protected from freezing downdrafts.
Remove all soot or other obstructions from the chimney that will
retard a free draft.
Type B venting is recommended with these heaters. See table 3
TECHNICAL DATA VENTING.
This water heater must be vented in compliance with all local
codes, the current revision of the National Fuel Gas Code (ANSI-
Z223.1) and with the Category I Venting Tables.
In Canada, venting shall conform to the requirements of the
current CAN/CGA B149.1-00 installation code.
If any parts of the vent system are exposed to ambient
temperatures below 35 degrees F (2 degrees C) they must be
insulated to prevent condensation.
• Do not connect the heater to a common vent or chimney with
solid fuel burning equipment. This practice is prohibited by
many local building codes as is the practice of venting gas
fired equipment to the duct work of ventilation systems.
• Where a separate vent connection is not available and the
vent pipe from the heater must be connected to a common
vent with an oil burning furnace, the vent pipe should enter
the smaller common vent or chimney at a point above the
large vent pipe.
CORRECT METHOD
OF VENT PIPE
INSTALLATION
INCORRECT INSTALLATION
WITH NO UPWARD
ANGLE
PROVIDE MAXIMUM VERTICAL RISE OF VENT PIPE DIRECTLY ABOVE
HEATER DRAFT HOOD BEFORE TURNING INTO HORIZONTAL RUN.
FIGURE 8
MULTIPLE HEATER MANIFOLD
Figure 9 and table 3 should be used for horizontally manifolding
two or more heaters. Also see MULTIPLE-UNIT INSTALLATIONS
of MECHANICAL VENTING section for induced draft applications.
FIGURE 9
WATER LINE CONNECTIONS
This manual provides detailed installation diagrams (see pages
16-22 of this manual) for typical methods of application for the
water heaters.
The water heater may be installed by itself, or with a separate
storage tank, on both single and two-temperature systems.
When used with a separate storage tank, the circulation may be
either by gravity or by means of a circulating pump. When a
circulating pump is used it is important to note that the flow rate
should be slow so that there will be a minimum of turbulence
inside the heater.
If a water heater is installed in a closed water system, contact
the water supplier or local plumbing inspector on how to control
this situation.
WATER (POTABLE) HEATING ANDSPACE HEATING
1. All piping components connected to this unit for space heating
applications shall be suitable for use with potable water.
2. Toxic chemicals, such as those used for boiler treatment,
shall NEVER be introduced into this system.
3. This unit may NEVER be connected to any existing heating
system or component(s) previously used with a non-potable
water heating appliance.
4. When the system requires water for space heating at
temperatures higher than required for domestic water
purposes, a tempering valve must be installed. Please refer
to installation diagrams on pages 16 through 22 in this manual
for suggested piping arrangements.

CAUTION

A closed system will exist if a check valve (without bypass),
pressure reducing valve (without bypass), or a water meter
(without bypass) is installed in the cold water line between the
water heater and street main (or well).
Excessive pressure may develop in such closed systems,
causing premature tank failure or intermittent relief valve
operation. This is not a warranty failure. An expansion tank or a
similar device may be required in the inlet supply line between
the appliance and the meter or valve to compensate for the
thermal expansion of the water.

SYSTEM CONNECTIONS

The system installation must conform to these instructions and
to the local code authority having jurisdiction. Good practice
requires that all heavy piping be supported.
THERMOMETERS (Not Supplied)
Thermometers should be obtained and field installed as shown
in the installation diagrams.
Thermometers are installed in the system as a means of
detecting the temperature of the outlet water supply.
RELIEF VALVE
This water heater is equipped with a combination temperature-
pressure relief valve that complies with the standard for relief
valves and automatic gas shutoff devices for hot water supply
system, ANSI Z21.22, for Canada see CAN/CSA 149.1-00. FOR
SAFE OPERATION OF THE WATER HEATER, THE RELIEF
VALVE(S) MUST NOT BE REMOVED OR PLUGGED.