A.O. Smith 315465-000 Water Heater User Manual


 
23
FOR YOUR INFORMATION
START UP CONDITIONS
CONDENSATE
Whenever the water heater is lled with cold water, some condensate
will form while the burner is on. A water heater may appear to be leaking
when in fact the water is condensate. This usually happens when:
a. A new water heater is lled with cold water for the rst time.
b. Burning gas produces water vapor in water heaters, particularly
high ef ciency models where ue temperatures are lower.
c. Large amounts of hot water are used in a short time and the re ll
water in the tank is very cold.
Moisture from the products of combustion condense on the cooler
tank surfaces and form drops of water which may fall onto the burner
or other hot surfaces to produce a “sizzling” or “frying” noise.
Because of the suddenness and amount of water, condensate water
may be diagnosed as a “tank leak”. After the water in the tank warms
up (about 1-2 hours), the condition should disappear.
Do not assume the water heater is leaking until there has been enough
time for the water in the tank to warm up.
An undersized water heater will cause more condensation. The water
heater must be sized properly to meet the family’s demands for hot
water including dishwashers, washing machines and shower heads.
Excessive condensate may be noticed during the winter and early
spring months when incoming water temperatures are at their
lowest.
Good venting is essential for a gas red water heater to operate
properly as well as to carry away products of combustion and water
vapor.
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
CLOSED WATER SYSTEMS
Water supply systems may, because of code requirements or such
conditions as high line pressure, among others, have installed devices
such as pressure reducing valves, check valves, and back ow preventers.
Devices such as these cause the water system to be a closed system.
THERMAL EXPANSION
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 harmful effects of thermal expansion.
Contact a local plumbing service agency to have a thermal expansion
tank installed.
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 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 ammable 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 ame 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.