A.O. Smith POWER VENT GAS, Installation And Operating Manual

38 www.hotwater.com 

 TEMPERATURE  REGULATION

FIGURE 35

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 temperatures be set for the 
lowest temperature which satis

fi

 es your hot water needs. 

This will also provide the most energy ef

fi

 cient operation 

of the water heater.

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, 
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 in

fi

 rm, or physically/

mentally handicapped. If anyone using hot water from this 
heater 

fi

 ts into one of these groups or if there is a local code 

or state law requiring a certain temperature water at the 
hot water tap, then you must take special precautions. In 
addition to using the lowest possible temperature setting 
that satis

fi

 es your hot water needs, a means such as a 

mixing valve, should be used at the hot water taps used 
by these people or at the water heater. Mixing valves are 
available at plumbing supply or hardware stores (see 
Figure 3). Follow manufacturer’s instructions for installation 
of the valves. Before changing the factory setting on the 
thermostat, read the “Temperature Regulation” section in 
this manual.

Never allow small children to use a hot water tap, or to draw 
their own bath water. Never leave a child or handicapped 
person unattended in a bathtub or shower.

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. The water temperature 
setting was factory set at the lowest temperature; 

THIS WATER HEATER IS EQUIPPED WITH AN 
ADJUSTABLE THERMOSTAT TO CONTROL WATER 
TEMPERATURE. 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 THE 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 WATER HEATER SHOULD BE LOCATED IN AN 
AREA WHERE THE GENERAL PUBLIC DOES NOT 
HAVE ACCESS TO SET TEMPERATURES.

SETTING THE WATER HEATER TEMPERATURE 
AT 120°F (49°C) WILL REDUCE THE RISK OF 
SCALDS. Some states require settings at speci

fi

 c lower 

temperatures.
The water temperature is controlled using the Temperature 
Control on the Display at the front of the unit (see Figure 
3). This control utilizes a temperature probe to determine 
the tank temperature. The primary temperature probe is 
located at the top of the tank.

The temperature may be adjusted from 90°F (32°C) to 
158°F (70°C). The thermostat was adjusted to 105°F 
(43°C) before the heater was shipped from the factory. It 
is recommended that lower water temperature 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 satis

fi

 es your hot water needs. This 

will also provide the most energy ef

fi

 cient operation of the 

water heater and minimize scale formation.

Valves for reducing the point-of-use temperature by mixing 
cold and hot water are available (see Figure 2). Also 
available are inexpensive devices that attach to faucets to 
limit hot water temperatures. Contact a licensed plumber 
or the local plumbing authority.

The table below shows the approximate time-to-burn 
relationship for normal adult skin. Short repeated heating 
cycles caused by small hot water uses can cause 
temperatures at the point of use to exceed the thermostat 
setting by up to 20°F (11°C). If you experience this type of 
use, you should consider using lower temperature settings 
to reduce scald hazards.