Whirlpool Residential Gas Water Heater Installation Instructions And Use & Care Manual page 13

Please note the following:
• The system should be installed only with piping that is
suitable for potable (drinkable) water such as copper,
CPVC, or polybutylene. This water heater must not be
installed using iron piping or PVC water piping.
• Use only pumps, valves, or fittings that are compatible
with potable water.
• Use only full flow ball or gate valves. The use of valves
that may cause excessive restriction to water flow is
not recommended.
• Use only 95/5 tin-antimony or other equivalent solder.
Any lead based solder must not be used.
• Piping that has been treated with chromates, boiler
seal, or other chemicals must not be used.
• Chemicals that may contaminate the potable water
supply must not be added to the piping system.
Closed System/Thermal Expansion
WARNING
Explosion Hazard
If the temperature and pressure relief valve
is dripping or leaking, have a qualified
person replace it.
Examples of a qualified person include:
licensed plumbers, authorized gas company
personnel, and authorized service
personnel.
Do not plug valve.
Do not remove valve.
Failure to follow these instructions can
result in death, or explosion.
As water is heated, it expands (thermal expansion). In
a closed system, the volume of water will grow. As the
volume of water grows, there will be a corresponding
increase in water pressure due to thermal expansion.
Thermal expansion can cause premature tank failure
(leakage). This type of failure is not covered under the
limited warranty. Thermal expansion can also cause
intermittent temperature-pressure relief valve operation:
water discharged from the valve due to excessive pressure
build up. The temperature-pressure relief valve is not
intended for the constant relief of thermal expansion. This
condition is not covered under the limited warranty.
A properly-sized thermal expansion tank should be
installed on all closed systems to control the effects of
thermal expansion. Contact a plumbing service agency or
your retail supplier regarding the installation of a thermal
expansion tank.
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