Instructions / Assembly

50
INSTALLATION INSTRUCTIONS
Plumbing
Water Supply (cont.)
Relief Valve
A new pressure-relief valve, complying with the
Standard for Relief Valves and Automatic Gas
Shut-Off Devices for Hot Water Supply Systems,
ANSI Z21.22/CSA 4.4, must be installed at the
HOT water outlet connection of the water heater
during installation. Local codes shall govern the
installation of any relief valves or place of purchase
for availability and installation information.
NOTICES:
• The following drawing illustrates a pressure-only
relief valve. If local codes require a combination
temperature and pressure-relief valve, you may
need to install an extension piece to ensure that
the valve probe is not directly in the flow path of
the water.
•
If local codes require that a temperature and
pressure-relief valve be installed, the manufacturer
recommends a type 40XL Watts temperature and
pressure-relief valve or equivalent model be used.
• Manual operation of relief valves should be
performed at least once a year.
• If the relief valve on the system discharges
periodically, a problem exists. Turn off the water
heater, unplug the unit, and call for service.
One end of the relief valve discharge line connects
to the HOT water outlet pipe as shown above.
The other end of the pipe should be routed to a
suitable drain to eliminate potential water damage.
For safe operation of the water heater, be sure
that:
• The pressure rating of the relief valve must not
exceed 150 psi (1,034 kPa) or the maximum
working pressure of the water heater. (See the
rating plate on the water heater.)
• The BTUH rating of the relief valve must equal or
exceed the BTUH input of the water heater. (See
the rating plate on the water heater.)
• No valve of any type should be installed between
the relief valve and the water heater.
• Discharge from the relief valve should be piped
to a suitable drain. Piping used should be of a
type approved for the distribution of hot water.
• HOT and COLD water lines should be insulated
up to the water heater. See page 51.
• The discharge line must be NO SMALLER than
the outlet of the relief valve. The drain line must
pitch downward to allow for complete drainage
of the line and the valve.
• The end of the discharge line should not be
threaded or concealed and should be protected
from freezing. No valve of any type, restriction,
or reducer coupling should be installed in the
discharge line.
Relief
Valve
Union
Union
Cold Water Supply
Shut-Off Valve
Cold Water
Supply Inlet
Hot Water
Supply Outlet
Relief Valve
Discharge Line