INSTALLATION
21
MAINS WATER SUPPLY
Where the mains water supply pressure exceeds that shown in the table below, an approved pressure
limiting valve is required and should be fitted as shown in the installation diagram
(refer to diagram on
page
34
)
.
Model
325, 410
Relief valve setting
1000 kPa
Expansion control valve setting *
850 kPa
Max. mains supply pressure
With expansion control valve
680 kPa
Without expansion control valve
800 kPa
Min. mains supply pressure
200 kPa
* Expansion control valve not supplied with the water heater.
TANK WATER SUPPLY
If the water heater is supplied with water from a tank supply and a minimum water supply pressure of
200 kPa at the water heater cannot be achieved, then a pressure pump system must be installed to allow the
heat pump circulator to operate and avoid air locks in the circuit. Care must be taken to avoid air locks. The
cold water line from the supply tank should be adequately sized and fitted with a full flow gate valve or ball
valve.
HOT WATER DELIVERY
This water heater can deliver water at temperatures
which can cause scalding.
A RheemPlus water heater will not deliver
temperatures exceeding 50°C, in accordance with
AS 3498. The risk of scald injury will be reduced.
It may be necessary to fit an additional temperature
limiting device to meet the requirements of
AS/NZS 3500.4 and / or regulatory and local
authorities.
CIRCULATED HOT WATER FLOW AND RETURN SYSTEM
A RheemPlus MPi 554 series heat pump water heater cannot be installed as part of a circulated hot water
flow and return system in a building.
REDUCING HEAT LOSSES
The cold water line to and the hot water line from the water heater must be insulated in accordance with the
requirements of AS/NZS 3500.4. The insulation must be weatherproof and UV resistant if exposed.
ANODE TYPES
The vitreous enamel lined cylinder of the water heater is only covered by the Rheem warranty when the total
dissolved solids (TDS) content in the water is less than 2500 mg/L and when the correct colour coded anode
is used. If an incorrect colour coded anode is used in the water heater, any resultant faults will not be
covered by the Rheem warranty. In addition, the use of an incorrect colour coded anode may shorten the life
of the storage tank. The black anode is typically fitted as standard (refer to
“Anode”
on page 12).
If an incorrect anode is used, there is also the possibility the anode may become overactive and hydrogen
gas could accumulate in the top of the water heater during long periods of no use. In areas where this is
likely to occur, the installer should instruct the householder on how to dissipate the gas safely (refer to
“Caution”
on page 13).
