Operation; Safety Precautions; Thermal Performance; Setting The Water Temperature - Rheem Residential Electric Models Use & Care Manual

A. Do turn off power to water heater if it has been subjected to over heating,
fire, flood or physical damage.
B. Do Not turn on water heater unless it is completely filled with water.
C. Do Not turn on water heater if cold water supply shut-off valve is closed.
D. If there is any difficulty in understanding or following the OPERATION or
MAINTENANCE instructions, it is recommended that a qualified person
or serviceman perform the work.
1. WATER TEMPERATURE SETTING AND THERMAL PERFORMANCE
Caution is important in installations where very high water temperatures
are needed for a required application. Water at high temperatures can
quickly cause severe scalding, especially in children or elderly people. It is
strongly recommended that great care be taken to prevent scalding. A
tempering valve must be used in any area used for washing or bathing,
and where access is available to the elderly or children. We also recom-
mend that the thermostats be set at the lowest possible setting to meet the
application. Please refer to the Thermostat Setting section of this manual
for additional information and recommendations.
One other reminder is to be sure that the T & P Valve is properly installed.
It is a plumbing code requirement in most parts of the country to plumb the
T & P Valve to discharge within six inches of the floor. This is clearly
described in the Installation section of this manual. Failure to do this is not
only a violation of the plumbing code, but a safety hazard for anyone near
the water heater in the event the T & P discharges. Not having the T & P
plumbed with a drain line also allows water to be potentially discharged
onto the top of the water heater if the valve opens. The consequence of
this could be inaccurate temperature sensing by the thermostats, if they
are cooled by the discharged water as it evaporates. Another negative
result could be saturated insulation, which would waste energy, be the
source of a high bill complaint and reduce the insulation's ability to support
the tank.
In conclusion, non-metallic water heaters are designed and built to provide
years of service. Having them properly installed and accurately adjusted is
essential if they are to perform reliably in the many challenging applications
in which they are installed.
2. WATER TEMPERATURE SETTING — To comply with safety regulations
the thermostats are factory set at 120° F. or less where local codes
require, and is usually sufficient for most household needs.
Maximum water temperatures occur just after the elements have shut off.
To find out exact temperature of the water being delivered, turn on a hot
water faucet and allow it to run until maximum temperature is reached,
then insert a thermometer in the water stream and read the temperature.
Safety and energy conservation are factors to be considered when select-
ing the water temperature setting of the water heater's thermostats . The
lower the temperature setting the greater the safety and savings in energy
and operating costs. If a different temperature setting is desired, read and
follow the following warnings and instructions.

Operation

SAFETY PRECAUTIONS

!
CAUTION
NEVER use this water heater unless it is completely full of water.
To prevent damage to the tank and heating elements the tank
must be filled with water. Water must flow from the hot water
faucet(s) before turning power "ON"
!
DANGER
There is a Hot Water SCALD Potential if the thermostat is set too
high.
NOTE: Households with small children or invalids may
require a 120° F. or lower thermostat setting to prevent
contact with "HOT" water.
Mixing valves for reducing point of use water temperature by mixing hot
and cold water in branch water lines are available. Contact a licensed
plumber of the local plumbing authority for further information.
The following chart may be used as a guide in determining the proper
water temperature for your home.
TIME / TEMPERATURE RELATIONSHIPS IN SCALDS
Temperature
120° F.
125° F.
130° F.
135° F.
140° F.
145° F.
150° F.
155° F.
RESETTING THE THERMOSTAT — It is recommended that the thermostat
remain at the factory setting for most normal applications. Water tempera-
ture adjustments can be changed as follows:
!
DANGER
Make certain power to water heater is OFF before removing jacket
access panel(s) FOR ANY REASON. Failure to do so could result
in property damage, bodily injury or death!
A. Remove the thermostat snap-in access panel cover. Insert finger into
latch hole on the bottom of the cover, and push up to release the latch.
Then pull forward to remove the cover and insulation. (See figure 9.)
8
Time to Produce Serious Burn
More than 5 minutes
1
1 / to 2 minutes
2
About 30 seconds
About 10 seconds
Less than 5 seconds
Less than 3 seconds
1
About 1 / seconds
2
About 1 second
Table courtesy of Shriners Burn Institute