Hot Water Delivery - Rheem 27 874 Series Owner's Manual And Installation Instructions

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 an 874 series water
heater and the hot water outlets in any ablution and public areas such as a bathroom, ensuite or public
amenities, 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 or public area.
The temperature limiting device used with an electronic continuous flow gas water heater should have:
• a specified minimum temperature differential between the hot water inlet and the tempered water outlet
of no greater than 10°C, and
• a specified maximum permitted pressure variation in the supply between the hot water inlet and the cold
water inlet of no less than 15%.
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
and pressure limiting valve 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
An 874 series water heater will not deliver temperatures exceeding 55°C in accordance with AS 3498. There
is no statutory requirement in AS/NZS 3500.4 to fit a temperature limiting device if this water heater is
installed in other than an early childhood centre, school, nursing home or a facility for young, aged, sick or
disabled people. Refer to
Gas Booster for a Solar Water Heater
The temperature limiting device used with an 874 series gas booster water heater as part of a solar water
heater installation must have the additional capability of receiving a hot water supply temperature of up to
99°C if the solar preheat water heater does not have an over temperature protection system to limit the water
to no greater than 90°C, such as the Rheem Premier Hiline thermosiphon closed circuit system.
Warning: Temperature controllers must not be fitted to this water heater as part of a solar water heater
system (874 series) because water at a temperature much higher than the controller setting can be
delivered. If a solar preheater has been installed to an existing water heater installation, then all controllers
must be disconnected and removed.
"Water Temperature Diagrams"
INSTALLATION – WATER HEATER
on page 48.
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