Rheem Thermal Manual
water to water Hot water
5
04/02/2021
Water Quality
The heat pump must be installed in accordance with this advice to be covered by the Rheem
Thermal warranty.
This heat pump 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 heat pump and its operation and / or life expectancy. If you are unsure of you water chemistry,
you may be able to obtain information from your local water supply authority. This heat pump should
only be connected to a water supply which complies with these guidelines for the Rheem Thermal
warranty to apply.
Change of Water supply
The changing or alternating from one water supply to another, e.g. a rain water tank supply, bore
water supply, desalinated water supply, public reticulated water supply or water bought in from
another supply, then water chemistry should be tested to ensure the water supply meets the
requirements given in these guidelines for the Rheem Thermal warranty to apply.
Saturation Index
The saturation index (SI) is used as a measure of the waters corrosive or scaling properties.
Where the saturation index is less than -1.0, the water is very corrosive and the Rheem Thermal
warranty does not apply to the heat pump. In a corrosive water supply, the water can attack copper
parts and cause them to fail.
Water which is scaling may be treated with a water softening device to reduce the saturation index
of the water.
Chloride and PH
Where the chloride level exceeds 250mg/l the Rheem Thermal warranty does not apply to the heat
pump. In a high chloride water supply, the water can corrode stainless steel parts and cause them
to fail.
Where the pH is less than 6.0 the Rheem Thermal warranty does not apply to the heat pump. pH is
a measure of wether the water is alkaline or acid. In an acidic water supply, the water can attack
stainless parts and cause them to fail.
Water with a pH less than 6.0 may be treated to raise the pH. The water supply from rainwater tank
in a metropolitan area is likely to be corrosive due to the dissolution of atmospheric contaminants.
Summary of water advice affecting the Rheem Thermal warranty
The heat pump is not suitable for certain water chemistries. Those chemistries are listed below. If
the heat pump is connected at any time to a water supply with the following chemistry, Rheem
Thermal’s warranty will not cover any resultant faults.
Water chemistry
Please maintain these water conditions or else Heat Exchanger failure may occur.
Saturation index (SI) > -1.0
Saturation index (SI) < +0.4
Chloride < 250 mg/L
pH >6.0
