Installation Manual

Demand Duo™ R-Series Installation and Operation Manual 43
Anodes
The storage tank is equipped with two magnesi-
um anodes designed to extend the life of the stor-
age tank. Slowly consumed over time, the anode
protects the glass-lined tank from corrosion. It is
strongly recommended to inspect the anodes
every two (2) years. If more than half of the an-
odes have been consumed, they should be re-
placed.
The longevity of the storage tank can be reduced
when a water softener is introduced to fight hard
water. Sodium salts added by a softener can
make the water extremely conductive; therefore,
the anodes are consumed at a faster rate. In
such conditions, the anodes should be inspected
on a yearly basis.
In certain conditions, the anodes may react with
the water, producing discolored or smelly water.
The most common complaint is hot water that
smells like rotten eggs. This is the result of the
reaction between the anode and hydrogen sul-
phide gas dissolved in the water, which is com-
mon in well systems. This issue can usually be
eliminated or reduced by changing the magnesi-
um anodes to aluminum anodes and by chlorinat-
ing the storage tank and plumbing system. If the
problem continues, special filtration equipment
may be required. Under no circumstances are the
anodes to be removed from the water heater on a
permanent basis.
Removal of the anodes will lead to premature
failure of the water heater and will void the
warranty.
Storage Tank
Drain water through the drain valve at least once
a year. This will remove excess sediment from
the bottom of the tank. This sediment, if allowed
to accumulate, will reduce the efficiency and the
life of the tank.
Draining the Storage Tank
To completely drain the storage tank:
1. Turn the power “OFF” to the system by
disconnecting power to the system. (The
system will not be fully shut down by simply
pressing the power button on the controller.)
2. Close the cold water supply manual shut-off
valve.
3. Connect one end of a garden hose to the
storage tank drain valve and put the other
end next to a free-flowing drain.
4. Open the drain valve by turning the knob
counter clockwise.
5. Open a hot water faucet to allow air into the
system.
Topics in this section
• Diagnostic Codes
• Replacement Parts
• Service/Maintenance Log
Cold Water
Supply Valve
Drain Valve
Anode Replacement
Procedure
1. Remove plastic
caps.
2. With 1-1/8 in. socket
wrench, remove the
anode.
Figure 39
Figure 40