Operating The Temperature Control System - A.O. Smith 300 Series Installation And Operating Manual

OPERATING THE TEMPERATURE CONTROL SYSTEM

It is recommended that lower water temperatures be used
to avoid the risk of scalding. It is further recommended,
in all cases, that the water temperature be set for the
lowest temperature which satisfies your hot-water needs.
This will also provide the most energy efficient operation
of the water heater.
Short repeated heating cycles caused by small hot-water
uses can cause a temperature increase of the hot water
by 20F° higher than the heater's temperature settings. If
you experience this type of use you should consider using
lower temperature settings to reduce scald hazards.
Should overheating occur or the gas supply fails to shut
off, turn off the main manual gas shut off valve to the
appliance (see Figure 1).
DANGER
HOT
HOT
BURN
HOT WATER CAN SCALD:
Water heaters are intended to produce hot water.
Water heated to a temperature which will satisfy space
heating, clothes washing, dish washing, cleaning and
other sanitizing needs can scald and permanently injure
you upon contact. Some people are more likely to be
permanently injured by hot water than others. These
include the elderly, children, the infirm, or physically/
mentally handicapped. If anyone using hot water fits into
one of these groups or if there is a local code or state law
requiring certain temperature water at the hot-water tap,
then you must take special precautions. In addition to
using lowest possible temperature setting that satisfies
your hot water needs, a means such as a mixing valve,
should be used at hot-water taps used by these people
or at the water heater (see Figure 7 and Figure 8). Follow
manufacturer's instructions for installation of the valves.
Before changing the factory setting on the thermostat, in
this manual, see Table 9.
100304526_2000545240 _Rev. 01
Water temperature over
125°F can cause severe
burns instantly resulting in
severe injury or death.
Children, the elderly and the
disabled are at highest risk
of scald injury.
Feel water before bathing or
showering.
Temperature limiting devices
such as mixing valves must
be installed when required
by codes and to ensure safe
temperatures at fixtures.
www.hotwater .com
The water heater should be located in an area where
the general public does not have access. If a suitable
area is not available, a cover should be installed over the
thermostat to prevent tampering.
This water heater is equipped with an adjustable
thermostat to control water temperature (see Figure 51).
Hot water temperatures required for automatic dishwasher
and laundry use can cause scald burns resulting in serious
personal injury and/or death. The temperature at which
injury occurs varies with the person's age and time of the
exposure. The slower response time of children, aged or
disabled persons increases the hazards to them. Never
allow small children to use a hot-water tap, or to draw their
own bath water. Never leave a child or disabled person
unattended in a bathtub or shower.
The hot setting shown on the dial is approximately 120°F .
This is a good starting point to set the temperature.
Setting the water heater temperature at 120°F will reduce
the risk of scalds.
The thermostat settings on the gas control valve are shown
in Figure 51.
The water temperature setting was factory set at the lowest
(VAC) temperature setting.
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