HTP PH100-55 - Temperature and Pressure Relief Valve; Backflow Preventer; Potable Expansion Tank

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C. TEMPERATURE AND PRESSURE RELIEF VALVE
To avoid water damage or scalding due to relief valve operation:
• Discharge line must be connected to relief valve outlet and run to a safe place of disposal.
Terminate the discharge line in a manner that will prevent possibility of severe burns or property
damage should the relief valve discharge.
• Discharge line must be as short as possible and the same size as the valve discharge connection
throughout its entire length.
• Discharge line must pitch downward from the valve and terminate at least 6” above the floor
drain, making discharge clearly visible.
• The discharge line shall terminate plain, not threaded, with a material serviceable for
temperatures of 375
o
F or greater.
• Do not pipe discharge to any location where freezing could occur.
• No shutoff valve may be installed between the relief valve and heater or in the discharge line. Do
not plug or place any obstruction in the discharge line.
• Test the operation of the relief valve after filling and pressurizing the system by lifting the lever.
Make sure the valve discharges freely. If the valve fails to operate correctly, immediately replace
with a new properly rated relief valve.
• Test T&P valve at least once annually to ensure the waterway is clear. If valve does not operate,
turn the heater “off” and call a plumber immediately.
• Take care whenever operating relief valve to avoid scalding injury or property damage.
FAILURE TO COMPLY WITH THE ABOVE GUIDELINES COULD RESULT IN FAILURE OF RELIEF
VALVE OPERATION, RESULTING IN POSSIBILITY OF SUBSTANTIAL PROPERTY DAMAGE,
SEVERE PERSONAL INJURY, OR DEATH.
Do not thread a cap or plug into the relief valve under any circumstances! Explosion and property
damage, serious injury, or death may result.
D. BACKFLOW PREVENTER
Use a backflow preventer specifically designed for water heater installations. This valve should be
installed on the cold water fill supply line per local codes.
E. POTABLE EXPANSION TANK
A potable hot water expansion tank is required to offset heated water expansion. In most city plumbing
systems, the water meter has a no return or back flow device built into the system to prevent back flowing
of water into city mains. Some local codes require back flow preventers on all incoming water supplies.
The hot water expansion tank must be listed for potable water use. The expansion tank should be located
on the cold inlet piping close to the water heater.
EXPANSION TANK AND MAKE-UP WATER
1. Ensure that the expansion tank is sized to correctly handle heater and system water volume and
temperature.