Rheem Optima Owner's Manual And Installation Instructions page 24

ANODE
The vitreous enamel lined cylinder of the water heater is only covered by
warranty when the total dissolved solids (TDS) content in the water is less than
2500 mg/L and when the correct colour coded anode is installed. The use of an
incorrect colour coded anode will void the cylinder warranty and may shorten
the life of the water heater cylinder.
The correct colour coded anode for the water supply being used must be
selected and fitted to the water heater for warranty to apply to the water heater
cylinder (refer to
on page 12). The black anode is typically fitted as standard.
Total Dissolved Solids
0 – 40 mg/L
40 – 150 mg/L
150 – 400 mg/L
400 – 600 mg/L
600 – 2500 mg/L
2500 mg/L +
If the water supply has a TDS greater than 150 mg/L and a green anode has
not been changed to a black anode, or if the TDS is greater than 600 mg/L and
the anode has not been changed to a blue anode, there is the possibility the
anode may become overactive and hydrogen gas could accumulate in the top
of the water heater during long periods of no use. In areas where this is likely to
occur, the installer should instruct the householder on how to dissipate the gas
safely (refer to "Caution"
"Water Supplies"
on page 12).
on page 11 and the
Anode colour code
Green or Black
Black or Blue
Blue (no cylinder warranty)
24
INSTALLATION
Anode Selection chart
Green
Black
Blue