Specifications
22 
WATER SUPPLIES 
This water heater must be installed in accordance with this advice to be covered by the  Aquamax 
warranty. 
This  water  heater  is  manufactured  to  suit  the  water  conditions  of  most  public  reticulated  water  supplies. 
However, there are some known water chemistries which can have detrimental effects on the water heater 
and its operation and / or  life  expectancy. If  you are  unsure  of  your  water  chemistry, you  may be  able  to 
obtain information from your local water supply authority. This water heater should only be connected to a 
water supply which complies with these guidelines for the Aquamax warranty to apply. 
CHANGE OF WATER SUPPLY 
The changing or alternating from one water supply to another can have a detrimental effect on the operation 
and / or life expectation of a heat exchanger in a continuous flow water heater. 
Where there is a  changeover  from one water supply to  another, e.g.  a rainwater  tank supply, bore water 
supply, desalinated water supply, public reticulated water supply or  water brought in from another supply, 
then water chemistry information  should  be sought from the supplier  or it should be tested to ensure the 
water supply meets the requirements given in these guidelines for the Aquamax warranty to apply. 
SATURATION INDEX 
The saturation index (SI) is used as a measure of the water‟s corrosive or scaling properties. 
In a corrosive water supply, the water can attack copper parts and cause them to fail. Where the saturation 
index is less than –1.0, the water is very corrosive and the Aquamax warranty does not apply to a copper 
heat exchanger in a continuous flow water heater. 
In  a  scaling  water supply  calcium  carbonate  is deposited  out  of  the  water  onto  any  hot  metallic  surface. 
Where the  saturation  index  exceeds  +0.80,  the  Aquamax  warranty  does  not  apply  to  a  copper  heat 
exchanger in a continuous flow water heater. 
Water which is scaling may be treated with a water softening device to reduce the saturation index of the 
water. 
Refer to the Saturation Index chart on page 22. 
-1.0
no warranty applies to a:
-continuous flow copper heat exchanger
SATURATION INDEX (SI)
GAS CONTINUOUS FLOW WATER HEATERS
WITHIN WARRANTY
SPECIFICATION
SATURATION INDEX
(calculated @ 80°C water temperature)
no warranty applies to a:
-continuous flow copper heat exchanger
+0.4 +0.80
very corrosive very scaling
scaling
corrosive










