State P6 20 10 MS K - Manual (Page 12)

For Your Information
Start Up Conditions
THERMAL EXPANSION
Water supply systems may, because of such events as high
line pressure, frequent cut-offs, the effects of water ham-
mer 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 sys-
tem 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 heater tank expands as it is
heated and increases the pressure of the water system. If
the relieving point of the water heater’s temperature-pres-
sure relief valve is reached, the valve will relieve the
excess pressure. The temperature-pressure relief valve is
not intended for the constant relief of thermal expan-
sion. This is an unacceptable condition and must be cor-
rected.
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 to relieve the pressure built by
thermal expansion in the water system. Expansion tanks
are available for ordering through a local plumbing con-
tractor. Contact the local plumbing contractor for assis-
tance 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 represent harmful or dangerous conditions.
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 asso-
ciated with the anode rod is one of a “rotten egg smell”.
This odor is derived from hydrogen sulfide gas dissolved
in the water. The smell is the 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 within the water heater.
(This harmless bacteria is non-toxic 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 hot water lines.
If the smelly water persists after the anode replacement
and chlorination treatment, we can only suggest that con-
tinuous chlorination and filtering conditioning equipment
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
RUMBLING NOISE
In some water areas, scale or mineral deposits will build
up on your heating elements. This buildup will cause a
rumbling noise. Follow “Element Cleaning/Replacement”
instructions to clean and replace the elements.
HIGH TEMPERATURE SHUT OFF SYSTEM
The water heater has a high limit shut off system with a
reset button located on the thermostat.
Follow the resetting instructions which refer to the high
limit behind the access panel.
1. Before beginning, turn “OFF” electrical power supply
to the water heater.
12
WARNING
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 possi-
bility of injury under these conditions, we recommend the
hot water faucet be opened for several minutes at the
kitchen sink 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 pre-
sent, 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.