Product Warranty

Residen al Hybrid Electric Heat Pump Water Heater Use and Care Guide • 27
TROUBLESHOOTING
WARNING! Because higher tempera-
tures increase the risk of scalding, if you
set the UIM se ng higher than 120°F,
Thermosta c Mixing Valves are par cu-
larly important (page 4).
Water Heater Sounds
During the normal operation of the
water heater, sounds or noises may be
heard. These noises are common and
may result from the following:
• Normal expansion and contraction
of metal parts during periods of
heat-up and cool-down.
• Sediment buildup on or around
the elements could create varying
amounts of noise and may cause
premature tank failure. Drain
and flush the tank as directed
under the “Draining and Flushing”
section.
• The heat pump compressor or fan
running.
Temperature Too High
If the water temperature is too hot:
• Adjust the UIM setting on the water
heater (see Step 12 in the installation
section of this manual).
• Install or adjust a Thermostatic
Mixing Valve (see manufacturer’s
instructions)
A nonfunc oning thermostat or a short-
ed hea ng element can cause extremely
hot water. If the Temperature and Pres-
sure Relief Valve (T&P Valve) releases
large amounts of very hot water, it is
likely due to a shorted hea ng element,
or more rarely a nonfunc oning thermo-
stat, or the thermostat does not fi t snug-
gly against the tank. Very high water
temperatures can also cause the Energy
Cut Off (ECO) to trip (see page26). 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 pressure
is only on the hot water side, the primary
causes of this are:
• Melted dip tube. Soldering copper
pipes while they are connected to the
water heater can melt the inside of the
hot and cold water connections or the
dip tube (cold water side). A melted
dip tube can restrict the flow of hot
water. If that’s the case, replace the dip
tube.
• Partially closed supply valve. Open the
water heater’s supply valve fully.
Insuffi cient or No Hot
Water or Slow Hot Wa-
ter Recovery:
WARNING! Because of the increased
risk of scalding, if you set the water
heater’s User Interface Module (UIM)
higher than 120°F, Thermosta c Mixing
Valves at each point-of-use are par cu-
larly important (page 4).
If the hot water is simply not warm
enough, there are several possible
causes:
• Thermostatic mixing valve faulty or
set too low.
• Temperature set point too low.
• Hot water usage pattern exceeds the
capability of the water heater in cur-
rent mode (See “Operating Mode
Descriptions”).
• Water connections to unit are
reversed (Disconnect and re-install
correctly).
• Leak in plumbing system (Check home
for any leaks and repair).
• Lower heating element not function-
ing properly.
• No power to the water heater (No
lights on the unit are on and dislay is
blank).
• Unit is in Vacation Mode.
• ECO tripped.
• Non-functioning upper temperature
sensor (refer to “Diagnostic Codes”
section E60).
• Air filter dirty (See “Air Filter Mainte-
nance” p.33).
• Out of position outlet j-tube (Assure
orientation of line on tube is in top
position).
• Lower heating element not function-
ing properly.
Thermosta c Mixing Valves. If the
hot water is simply not warm enough,
make sure the faucet you are checking
doesn’t have a defec ve Thermosta c
Mixing Valve. If these devices fail, they
can reduce the amount of hot water the
shower or faucet delivers even though
there is plenty of hot water in the tank.
Always check the water temperature at
several faucets to make sure the prob-
lem is not in a faucet or shower control.
TROUBLESHOOTING