Rheem 31202519V Owner's Manual And Installation Instructions page 20

WATER SUPPLIES
SUMMARY OF WATER CHEMISTRY ADVICE AFFECTING WARRANTY
The water heater and its components are not suitable for certain water
chemistries. Those chemistries are listed below. If the water heater is connected
at any time to a water supply with the following water chemistry, the Rheem
warranty will not cover any resultant faults on the components listed below:
Water Chemistry
Total Dissolved Solids (TDS) > 600 mg/L
(black colour coded anode installed)
Total Dissolved Solids (TDS) < 40 mg/L
(black colour coded anode installed)
Saturation Index (SI) < -1.0
Saturation Index (SI) > +0.4
(if expansion control valve is not fitted)
Saturation Index (SI) > +0.8
Component
water heater cylinder
water heater cylinder
copper sheathed heating unit
water heater cylinder
temperature pressure relief valve
standard watts density heating unit
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