Installation & Operation Manual
60
8
Domestic water heaters
Location of Cold Water Supply Piping Connections
Incorrect piping of the cold water supply to the system may result
in excessive low temperature operation causing condensate
formation on the primary heat exchanger and operational
problems. The cold water supply piping must be installed in
the discharge piping from the heater to the storage tank. This
allows the cold water to be tempered in the storage tank before
entering the heater. See typical installation drawings provided
in this manual for correct piping (FIG.’s 8-1 thru 8-4). Higher
water temperatures reduce the volume of condensate formed.
CAUTION
Setting the temperature selector to higher
settings provides hotter water, which
increases the risk of scald injury.
WARNING
Should overheating occur or the gas supply
fail to shut off, do not turn off or disconnect
the electrical supply to the pump. Instead,
shut off the gas supply at a location external
to the appliance.
Optional adjustable auxiliary high water
temperature limit control
IMG00600
ADJUSTABLE
AUXILIARY
HIGH WATER
TEMPERATURE
LIMIT CONTROL
(OPTION)
Figure 8-6_Adjustable Auxiliary High Water Temperature
Limit Control
A high limit control is located on the inside of the left front
panel, as shown in FIG. 8-6. The setting of this control knob
limits maximum discharge water temperature. The water heater
temperature limit control is adjustable up to a maximum setting
of 210°F (99°C). This water heater also includes a fixed high
water temperature limit control set to 200° (93.3°C).
Thermal expansion
A relief valve that discharges periodically may be due to thermal
expansion in a closed system. A water heater installed in a
closed system, such as one with a backflow preventer or check
valve installed in the cold water supply, shall be provided with
means to control expansion. Contact the water supplier or local
plumbing inspector on how to correct this situation. Never
plug or cap the relief valve discharge.
Cathodic protection
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. To prevent
the possibility of injury under these conditions, we recommend
the hot water faucet be open for several minutes at the kitchen
sink before you use any electrical appliance which is connected
to the hot water system. If hydrogen is present, there will be
an unusual sound such as air escaping through the pipe as the
hot water begins to flow. There should be no smoking or open
flames near the faucet at the time it is open.
NOTICE
The high limit control will not reset until the
water temperature has dropped below the
setpoint of the high limit.
