Connecting A Pressure Relief Valve - Navien NPE-180A2 Installation Manual

3.4.6 Connecting a Pressure Relief Valve

WARNING
Improper installation of the pressure relief valve
may result in property damage, personal injury,
or death. Follow all instructions and guidelines
when installing the pressure relief valve. The
valve should be installed only by a licensed
professional.
To complete the installation of the water heater,
you must install an approved
PSI pressure relief valve on the hot water outlet. The
water heater has a built-in high temperature shut off
switch, so install a "pressure only" relief valve. This
valve is not supplied, but is required. The following
examples are approved for use with the water
heater:
Wilkins P-1000A (Zurn Industries)
●
Conbraco 17-402-04
●
Watts Industries 3L (M7)
●
Cash Acme FWL-2, / in
3
●
4
The pressure relief valve should be placed as close
to the water heater as possible. No other valve
should be placed between the pressure relief valve
and the water heater.
Pressure
Relief Valve
Shut-off Valve
Gas Hot Water
WARNING
To avoid water damage or scalding, direct the
discharge line to a safe place for disposal.
36 Installing the Water Heater
/ in, maximum 150
3
4
Cold Water
When installing the valve, follow these guidelines:
Ensure that the discharge capacity of the pressure
●
relief valve is equal to or greater than the
maximum pressure rating of the water heater.
Ensure that the maximum BTU/H rating on the
●
pressure relief valve is equal to or greater than the
maximum input BTU/H rating of the water heater.
Direct the discharge piping of the pressure relief
●
valve so that hot water will not splash on anyone
or any nearby equipment.
Attach the discharge line to the pressure relief
●
valve and run the end of the line to within 6 - 12
in (150 - 300 mm) of the floor drain, making
discharge clearly visible.
Ensure that the discharge line will allow free and
●
complete drainage without restriction. Do not
install a reducing coupling or other restriction on
the discharge line.
Do not direct the discharge line to a location
●
where freezing could occur.
Ensure that the discharge line is not plugged or
●
obstructed.
After filling and pressurizing the system, test
●
the relief valve operation by lifting the lever. If
the valve fails to operate correctly, immediately
replace the relief valve.
If the relief valve discharges periodically, this may
●
be due to thermal expansion in a closed water
supply system. Contact the water supplier or
local plumbing inspector on how to correct this
situation. Do not plug the relief valve.
CAUTION
To avoid potential property damage or
●
personal injury, check the pressure relief
valve at least once every three years by
manually operating the valve to ensure
proper operation.
Before manually operating the valve, check
●
the discharge line and make sure that the
hot discharge water will not cause personal
injury or property damages. Contact with
the discharged water may result in severe
personal injury.