Replacement Parts; Service/Maintenance Log; Warranty - Rinnai Demand Duo H Series Installation And Operation Manual

Topics in this section

• Replacement Parts

• Service/Maintenance Log

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 has been consumed, they should be re-
placed. Instructions on how to change the anodes
can be obtained from the manufacturer.
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
chlorinating the storage tank and plumbing sys-
tem. If the problem continues, special filtration
equipment may be required. Under no circum-
stances 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.

Anode Replacement
Procedure
1. Remove plastic caps.
2. With 1-1/8 in. socket
wrench, remove the
anode.
Demand Duo™ H-Series Installation and Operation Manual
Figure 59
Storage Tank
Drain a pail of water through the drain valve at
least once a year. This will remove excess sedi-
ment from the bottom of the tank. This sediment,
if allowed to accumulate, will reduce the efficien-
cy 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 un-
plugging 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.
Figure 60
Drain Valve
Cold Water
Supply Valve
50