For Your Information; Start Up Conditions; Smoke/Odor; Thermal Expansion - A.O. Smith ARGSS02708 Instruction Manual

START UP CONDITIONS

SMOKE/ODOR

It is not uncommon to experience a small amount of smoke and
odor during the initial start-up. This is due to burning off of oil from
metal parts, and will disappear in a short while.

THERMAL EXPANSION

Water supply systems may, because of such events as high line
pressure, frequent cut-offs, the effects of water hammer among
others, have installed devices such as pressure reducing valves,
check valves, back flow preventers, etc. to control these types of
problems. When these devices are not equipped with an internal
by-pass, and no other measures are taken, the devices cause the
water system to be closed. As water is heated, it expands (thermal
expansion) and closed systems do not allow for the expansion of
heated water.
The water within the water tank expands as it is heated and
increases the pressure of the water system. If the relieving point
of the water heater 's temperature-pressure relief valve is
reached, the valve will release the excess pressure. The
temperature-pressure relief valve is not intended for the
constant relief of thermal expansion. This is an unacceptable
condition and must be corrected. It is recommended that any
devices installed which could create a closed system have a
by-pass and/or the system have an expansion tank or device to
relieve the pressure built by thermal expansion in the water
system. Expansion tanks are available for ordering through a
local plumbing contractor. Contact the local water heater supplier
or service agency for assistance in controlling these situations.

STRANGE SOUNDS

Possible noises due to expansion and contraction of some metal
parts during periods of heat-up and cool-down do not necessarily
represent harmful or dangerous conditions.
Condensation causes sizzling and popping within the burner area
during heating and cooling periods and should be considered normal.
See "Condensate" in this section.

OPERATIONAL CONDITIONS

SMELLY WATER

In each water heater there is installed at least one anode rod (see
parts section) for corrosion protection of the tank. Certain water

FOR YOUR INFORMATION

conditions will cause a reaction between this rod and the water. The
most common complaint associated with the anode rod is one of a
"rotten egg smell" in the hot water. The smell is a result of four factors
which must all be present for the odor to develop:
a. A concentration of sulfate in the supply water.
b. Little or no dissolved oxygen in the water.
c. A sulfate reducing bacteria which has accumulated within the
water heater (this harmless bacteria is nontoxic to humans).
d. An excess of active hydrogen in the tank. This is caused by the
corrosion protective action of the anode.
Smelly water may be eliminated or reduced in some water heater
models by replacing the anode(s) with one of less active material,
and then chlorinating the water heater tank and all water lines. Contact
the local water heater supplier or service agency for further information
concerning an Anode Replacement Kit and this chlorination treatment.
If the smelly water persists after the anode replacement and
chlorination treatment, we can only suggest that chlorination or aeration
of the water supply be considered to eliminate the water problem.
Do not remove the anode leaving the tank unprotected. By doing
so, all warranty on the water heater tank is voided.

"AIR" IN HOT WATER FAUCETS

HYDROGEN GAS: Hydrogen gas can be produced in a hot water
system that has not been used for a long period of time (generally
two weeks or more). Hydrogen gas is extremely flammable and
explosive. To prevent the possibility of injury under these conditions,
we recommend the hot water faucet, located farthest away, be
opened for several minutes before any electrical appliances which
are connected to the hot water system are used (such as a
dishwasher or washing machine). If hydrogen gas is present, there
will probably be an unusual sound similar to air escaping through
the pipe as the hot water faucet is opened. There must be no
smoking or open flame near the faucet at the time it is open.
HIGH WATER TEMPERATURE SHUT OFF SYSTEM
This water heater is equipped with an automatic gas shut-off system.
This system works when high water temperatures are present. Turn
"OFF" the entire gas supply to the water heater. The high temperature
shut-off is built into the gas control valve. It is non-resettable. If the
high temperature shut-off activates, the gas control valve must be
replaced. Contact your gas supplier or service agency.
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