Rheem Water Star Owner's Manual And Installation Instructions page 17

INSTALLATION
HOT WATER DELIVERY
This water heater can deliver water at temperatures which can cause scalding.
It is necessary and we recommend that a temperature limiting device be fitted
between a Water Star water heater and the hot water outlets in any ablution
area such as a bathroom or ensuite, to reduce the risk of scalding. The
installing plumber may have a legal obligation to ensure the installation of this
water heater meets the delivery water temperature requirements of
AS/NZS 3500.4 so that scalding water temperatures are not delivered to a
bathroom, ensuite or other ablution area.
Where the Water Star is installed with a continuous flow water heater and a
temperature limiting device is installed adjacent to the water heater, the cold
water line to the temperature limiting device must be branched off the cold
water line before the continuous flow water heater. It can be either before or
after the isolation valve, pressure limiting valve and non return valve (if an ECV
is installed) to the continuous flow water heater. If an expansion control valve is
required, it must always be installed after the non return valve and be the last
valve prior to the continuous flow water heater.
Two Temperature Zones Using a Temperature Limiting Device
Water Star with Continuous Flow Water Heater – without an ECV
If a pressure limiting valve is installed on the cold water line to the water heater
LEGEND
and the cold water line to a temperature limiting device branches off before this
valve or from another cold water line in the premises, then a pressure limiting
valve of an equal pressure setting may be required prior to the temperature
limiting device.
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