Rheem Electric Domestic Water Heater Installation And Owner's Manual page 20

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 Rheemglas or Optima 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 a temperature limiting device is installed adjacent to the water heater,
the cold water line to the temperature limiting device can be branched off the
cold water line either before or after the isolation valve, pressure limiting valve
and non return valve to the 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 water heater.
If a pressure limiting valve is installed on the cold water line to the water heater
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.
Two Temperature Zones Using a Temperature Limiting Device
LEGEND
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