A.O. Smith ProLine Master Installation Manual
Residen al Electric Water Heater Use and Care Guide • 19
TROUBLESHOOTING
necessary (see page 21).
Temperature Too High
If the water temperature is too hot:
• Install or adjust the Thermostatic
Mixing Valves for each point-of-use
(see manufacturer’s instructions), or
• Adjust the thermostat(s) on the
water heater (see Step 10 in the
installation section of this manual).
A nonfunc oning thermostat or a
shorted hea ng element can cause
extremely hot water. If the Temperature
and Pressure Relief Valve (T&P Valve)
releases large amounts of very hot wa-
ter, it is likely due to a shorted hea ng
element, or more rarely a nonfunc on-
ing thermostat, or the thermostat does
not fi t snuggly against the tank. Very
high water temperatures can also cause
the Energy Cut Off (ECO) to trip (see
page 18). Turn power off un l this
problem is fi xed.
Low Water Pressure
Check both the cold and hot water at a
sink to determine if the lower pressure
is only on the hot water side. If both hot
and cold faucets have low pressure, call
your local water u lity. If the low pres-
sure is only on the hot water side, the
primary causes of this are:
• Melted heat traps or dip tube. Solder-
ing copper pipes while they are con-
nected to the water heater can melt
the heat traps inside the hot and cold
water connections or the dip tube
(cold water side). Melted heat traps or
a melted dip tube can restrict the flow
of hot water. If that’s the case, replace
the heat traps or dip tube.
• Partially closed supply valve. Open
the water heater’s supply valve fully.
Drips from T&P Relief
Valve Discharge Pipe
A small amount of water dripping from
the Temperature and Pressure (T&P)
Relief Valve usually means the home’s
water pressure is too high or you need
a properly sized and pressurized Ther-
mal Expansion Tank. Refer to Step 1 in
the Installa on sec on of this manual
for more informa on. A large amount
of hot water coming from the T&P
discharge pipe may be due to the tank
overhea ng.
WARNING! Do not cap or plug the
T&P relief valve or discharge pipe,
and do not operate the water heater
without a func oning T&P Relief Valve
- this could cause an explosion.
Water pressure too high. High water
pressure can cause the T&P Relief
Valve to drip. Install a Pressure Reduc-
ing Valve (PRV) on the main cold water
supply line. Adjust the PRV to between
50 and 60 psi.
Thermal Expansion Tank. Install a
Thermal Expansion Tank. If a Thermal
Expansion Tank is already installed and
the T&P Relief Valve discharge pipe
drips, the Thermal Expansion Tank may
be pressurized to the wrong pressure or
the internal bladder may be defec ve.
Refer to the instruc ons that came with
the Thermal Expansion Tank for more
informa on.
Debris. In rare cases, debris can s ck
inside the T&P Relief Valve preven ng
the valve from sea ng fully. In that case,
the T&P Relief Valve discharge pipe will
drip. You may be able to clear debris
from the T&P Relief Valve by manu-
ally opera ng the valve, allowing small
quan es of water to fl ush out the
debris. Refer to the T&P Relief Mainte-
nance sec on of this manual.
WARNING! When manually operat-
ing the temperature-pressure relief
valve, make sure that no one is in front
of or around the discharge outlet. The
water may be extremely hot and could
cause severe burns. Also ensure that
the water discharge will not cause
property damage.
If the water pressure is between 50
and 60 psi, a Thermal Expansion Tank
is installed and properly pressurized,
and the valve has been cleared of any
debris, and it s ll drips, the valve may
be broken—have a qualifi ed person
replace the T&P relief valve.
Water Odor
Harmless bacteria normally present in
tap water can mul ply in water heat-
ers and give off a “ro en egg” smell.
Although elimina ng the bacteria that
causes “smelly water” with a Chlorina-
on system is the only sure treatment,
in some cases, the standard anode rod
that came with your water heater can
be replaced with a special zinc anode
rod which may help reduce or eliminate
the odor. Contact a qualifi ed person.
NOTE: To protect the tank, an anode
rod must be installed in the water
heater at all mes or the warranty is
void.
In cases where the “ro en egg” smell
is pronounced, you can raise the tank
temperature to 140°F in order to re-
duce bacteria growth in the tank.
WARNING! Because higher tempera-
tures increase the risk of scalding, if
you set the thermostat(s) higher than
120°F, Thermosta c Mixing Valves
at each point-of-use are par cularly
important (page 4).
TROUBLESHOOTING