Rheem Water Star Technical Document

This water heater must be installed and serviced by an authorised person.
Please leave this guide with the householder.
Owner’s Guide
and
Installation Instructions
Electric Water Heater

PATENTS
This water heater may be protected by one or more patents or registered designs
in the name of Rheem Australia Pty Ltd.
TRADEMARKS
®Registered trademark of Rheem Australia Pty Ltd.
TM Trademark of Rheem Australia Pty Ltd.
Note: Every care has been taken to ensure the accuracy in preparation of this
publication. No liability can be accepted for any consequences,
which may arise as a result of its application.
Notice to Victorian Customers from the
Victorian Plumbing Industry Commission.
This water heater must be installed by a licensed person
as required by the Victorian Building Act 1993.
Only a licensed person will give you a Compliance Certificate, showing that
the work complies with all the relevant Standards. Only a licensed person will
have insurance protecting their workmanship for 6 years. Make sure you use
a licensed person to install this water heater and ask for your Compliance
Certificate.

3
CONTENTS
HOUSEHOLDER - We recommend you read pages 4 to 14.
The other pages are intended for the installer
but may be of interest
About Your Water Heater............................................................4
Regular Care ................................................................................8
Water Supplies...........................................................................10
Save A Service Call ...................................................................12
Installation..................................................................................15
Connections –Plumbing ..........................................................21
Connections –Electrical...........................................................25
Commissioning..........................................................................28
Draining The Water Heater .......................................................29
Warranty.....................................................................................31

4
ABOUT YOUR WATER HEATER
MODEL TYPE
The Rheem®Water Star water heater you have chosen can be installed indoor
or outdoor. The Water Star has been designed to be installed with a continuous
flow gas water heater.
Where the water heater is installed with a continuous flow gas water heater and
a hot tap is turned on, the Water Star commences to deliver hot water
immediately from its outlet. This continues until hot water from the continuous
flow water heater reaches the transfer valve in the Water Star water heater. At
this point the transfer valve commences to redirect and the hot water supplied
by the continuous flow water heater is diverted to the hot tap. This conserves
water as usable hot water is delivered to the tap faster.
The Water Star water heater must not be installed with a continuous flow
water heater that is rated to deliver temperatures not exceeding 50°C in
accordance with AS 3498.
Warning: Temperature controllers must not be fitted to a continuous flow
water heater when a Water Star water heater is installed because water at a
temperature much higher than the controller setting can be delivered.
Water is stored in a copper cylinder and
heated by the electric immersion heating
unit. The thermostat controls the
temperature.
Automatic safety controls are fitted to the
water heater to provide safe and efficient
operation.
MAINS PRESSURE
The water heater is designed to operate at
mains pressure by connecting directly to the
mains water supply. If the mains supply
pressure in your area exceeds that shown
on page 16, a pressure limiting valve must
be fitted. The supply pressure should be
greater than 350 kPa for true mains
pressure operation to be achieved.

ABOUT YOUR WATER HEATER
5
HOW HOT SHOULD THE WATER BE?
The Water Star water heater features a
fixed setting thermostat, which heats the
water to a temperature of 70°C.
To meet the requirements of the National
Plumbing Standard the temperature of the
stored water must not be below 60°C.
HOTTER WATER INCREASES THE RISK
OF SCALD INJURY
This water heater can deliver water at
temperatures which can cause scalding.
Check the water temperature before use,
such as when entering a shower or filling a
bath or basin, to ensure it is suitable for the
application and will not cause scald injury.
We recommend and it may also be required by regulations that an approved
temperature limiting device be fitted into the hot water pipe work to the
bathroom and ensuite when a Water Star water heater is installed. This will
keep the water temperature below 50°C at the bathroom and ensuite. The risk
of scald injury will be reduced and still allow hotter water to the kitchen and
laundry.
WARNING
This water heater is only intended to be operated by persons who have the
experience or the knowledge and the capabilities to do so. This water heater is
not intended to be operated by persons with reduced physical, sensory or
mental capabilities i.e. the infirm, or by children. Children should be supervised
to ensure they do not interfere with the water heater.
This water heater uses 240 V AC power for the electrically operated
components. The removal of the front cover will expose 240 V wiring. It must
only be removed by an authorised or qualified person.
The water heater is fitted with a power supply cord and plug and must be
plugged into a weatherproof electrical outlet if installed outdoors. Take care not
to touch the power plug with wet hands.
minimum recommended
stored water temperature
Water Star thermostat
setting (not adjustable)
maximum recommended
supply temperature to
bathrooms and ensuites

ABOUT YOUR WATER HEATER
6
SAFETY
This water heater is supplied with a temperature limiting valve, a thermostat, an
over-temperature cut-out, and a combination temperature pressure relief valve.
These devices must not be tampered with or removed. The water heater must
not be operated unless each of these devices is fitted and is in working order.
The operation of the over-temperature cut-out on the thermostat indicates a
possibly dangerous situation. If the over-temperature cut-out operates, it must
not be reset and the water heater must be serviced by an authorised or
qualified person.
If the power supply cord or plug to the water heater is damaged, it must be
replaced by an authorised person in order to avoid a hazard. The power supply
cord and plug must be replaced with a genuine replacement part available from
Rheem. Phone Rheem Service or their nearest Accredited Service Agent to
arrange for an inspection.
Warning: For continued safety of this water heater it must be installed,
operated and maintained in accordance with the Owner’s Guide and Installation
Instructions.
The warranty can become void if relief valves or other safety devices are
tampered with or if the installation is not in accordance with these
instructions.
THERMOSTAT
The thermostat automatically controls the electricity supply to the heating unit
so a constant temperature is maintained. The thermostat and its protective over
temperature cut out is mounted inside the front cover of the water heater. There
is no need to switch the water heater off when it is not in use, except when you
are on an extended holiday. The thermostat is fully automatic and power is only
used when heating is required.
The thermostat on a Water Star has a fixed setting at 70°C. This cannot be
adjusted.
TO TURN OFF THE WATER HEATER
If you plan to be away from home for only a few nights, we suggest you leave
the water heater switched on.
If it is necessary to turn off the water heater:
Switch off the electrical supply at the isolating switch to the water heater.
Unplug the power supply cord from the power outlet.
Close the cold water isolation valve at the inlet to the water heater.

ABOUT YOUR WATER HEATER
7
TO TURN ON THE WATER HEATER
Open the cold water isolation valve fully on the cold water line to the water
heater.
If not already connected to the Water Star or to another power outlet, plug in
the power supply cord of the continuous flow water heater at the electrical
socket on the underside of the Water Star.
Plug in the power supply cord of the Water Star at the power outlet.
Note: Do not plug the three pin plug from the Water Star water heater into
the power outlet on the underside of this water heater.
Switch on the electrical supply at the isolating switch to the water heater.
GOING ON HOLIDAY?
If you plan to be away from home for one or two nights, we suggest you leave
the water heater switched on. However, if you plan to stay away more than a
few nights, conserve energy by switching the water heater off at the isolating
switch.
HOW DO I KNOW IF THE WATER HEATER IS INSTALLED CORRECTLY?
Installation requirements are shown on pages 15 to 19. The water heater must
be installed by an authorised person and the installation must comply with
National Standards AS/NZS 3500.4, AS/NZS 3000 and all local codes and
regulatory authority requirements. In New Zealand the installation must
conform with the New Zealand Building Code.
Warning: Temperature controllers must not be fitted to a continuous flow
water heater when a Water Star water heater is installed because water at a
temperature much higher than the controller setting can be delivered. If a Water
Star is installed to an existing continuous flow water heater installation, then all
controllers must be disconnected and removed.
DOES THE WATER CHEMISTRY AFFECT THE WATER HEATER?
The water heater is suitable for most public water supplies, however some
water chemistries may have detrimental effects on the cylinder and fittings. If
you are in a known harsh water area you must read page 10. If you are not
sure, have your water chemistry checked against the conditions described on
page 10.
HOW LONG WILL THE WATER HEATER LAST?
There are a number of factors that will affect the length of service the water
heater will provide. These include the water chemistry, the water pressure, the
water temperature (inlet and outlet) and the water usage pattern. However,
your water heater is supported by a comprehensive warranty (refer to page 32).

8
REGULAR CARE
TEMPERATURE PRESSURE RELIEF VALVE
This valve is near the top of the water
heater and is essential for its safe
operation. It is possible for the valve to
release a little water through the drain line
during each heating period. This occurs as
the water is heated and expands by
approximately 1/50 of its volume.
Continuous leakage of water from the valve
and its drain line may indicate a problem
with the water heater (refer to
“Temperature Pressure Relief Valve
Running” on page 13).
Warning: Never block the outlet of this
valve or its drain line for any reason.
The TPR valve connects to the top of the
cylinder and is located underneath the front
cover. The easing lever on the valve can
be accessed by removing the plastic cap
on the top of the water heater. Replace the
cap when the easing lever has been
operated.
Operate the easing lever on the
temperature pressure relief valve once
every six months. It is very important you
raise and lower the lever gently.
DANGER: Failure to do this may result
in the water heater cylinder failing, or under
certain circumstances, exploding.
If water does not flow freely from the drain line when the lever is lifted, then the
water heater should be checked by the Rheem Service or their nearest
Accredited Service Agent.
The temperature pressure relief valve should be checked for performance or
replaced at intervals not exceeding 5 years, or more frequently in areas where
there is a high incidence of water deposits (refer to “Water Supplies” on
page 10).
water
heater
drain
line
lift until water
flows from the
drain line –
lower gently
hot
water
outlet

REGULAR CARE
9
EXPANSION CONTROL VALVE
In many areas, including South Australia, Western Australia and scaling water
areas, an expansion control valve is fitted to the cold water line to the
continuous flow water heater. The expansion control valve may discharge a
small quantity of water from its drain line during the heating period instead of
the temperature pressure relief valve on the Water Star water heater.
Operate the easing lever on the expansion control valve once every six
months. It is very important you raise and lower the lever gently. The
expansion control valve should be checked for performance or replaced at
intervals not exceeding 5 years, or more frequently in areas where there is a
high incidence of water deposits.

10
WATER SUPPLIES
This water heater must be installed in accordance with this advice to be
covered by the warranty.
This water heater 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 water heater and its operation
and / or life expectancy. If you are unsure of your water chemistry, you may be
able to obtain information from your local water supply authority. This water
heater should only be connected to a water supply which complies with these
guidelines for the water heater warranty to apply.
Due to the nature of the water chemistry the copper cylinder is not covered by
the water heater warranty when this water heater is connected to the public
water supply in the Redlands Shire in Queensland.
SATURATION INDEX
The saturation index (SI) is used as a measure of the water’s corrosive or
scaling properties.
In a corrosive water supply, the water can attack copper parts and cause them
to fail.
Where the saturation index is less than –1.0, the water is very corrosive and
warranty does not apply to a copper cylinder in a Water Star water heater.
In a scaling water supply calcium carbonate is deposited out of the water onto
any hot metallic surface.
Where the saturation index exceeds +0.40, the water is very scaling. An
expansion control valve must be fitted on the cold water line after the non-
return valve to protect and for warranty to apply to the temperature pressure
relief valve and water heater cylinder.
Where the saturation index exceeds +0.80, warranty does not apply a copper
cylinder in a Water Star water heater or its heating unit.
Water which is scaling may be treated with a water softening device to reduce
the saturation index of the water.
Refer to the Saturation Index chart on page 11.
Refer to the cold water connection detail on page 22 for the position of the
expansion control valve.

WATER SUPPLIES
11
-1.0
no warranty applies to a:
temperature pressure relief valve or a
water heater cylinder unless an
expansion control valve is fitted.
no warranty applies to a:
-copper cylinder
SATURATION INDEX (SI)
WATER STAR WATER HEATER
WITHIN WARRANTY
SPECIFICATION
SATURATION INDEX
(calculated @ 80°C water temperature)
no warranty applies to a:
-standard watts density heating unit -copper cylinder
+0.4 +0.80
very corrosive very scaling
scaling
corrosive
CHANGE OF WATER SUPPLY
The changing or alternating from one water supply to another can have a
detrimental effect on the operation and / or life expectation of a water heater
cylinder, a temperature pressure relief valve and a heating unit.
Where there is a changeover from one water supply to another, e.g. a rainwater
tank supply, bore water supply, desalinated water supply, public reticulated
water supply or water brought in from another supply, then water chemistry
information should be sought from the supplier or it should be tested to ensure
the water supply meets the requirements given in these guidelines for warranty
to apply.
SUMMARY OF WATER CHEMISTRY ADVICE AFFECTING WARRANTY
The warranty of this water heater does not apply on the components listed
below if the water heater is connected at any time to a water supply with water
chemistry of:
Water Chemistry
Component
Saturation Index (SI) < -1.0
copper water heater cylinder
Saturation Index (SI) > +0.4
(if expansion control valve is not fitted)
copper water heater cylinder
temperature pressure relief valve
Saturation Index (SI) > +0.8
standard watts density heating unit

12
SAVE A SERVICE CALL
Check the items below before making a service call. You will be charged for
attending to any condition or fault that is not related to the manufacture or
failure of a part.
Refer also to “Save a Service Call” in the owner’s guide supplied with the
continuous flow water heater for additional information.
NOT ENOUGH HOT WATER (OR NO HOT WATER)
Is the electricity switched on?
Inspect the isolating switch at the water heater and ensure it is turned on.
Temperature pressure relief valve running
Is the relief valve discharging too much water?
Refer to “Temperature Pressure Relief Valve Running” on page 13.
WATER TEMPERATURE TOO HIGH
A Water Star has a fixed thermostat setting of 70°C. When a hot tap is turned
on, hot water delivered from the Water Star will be up to this temperature.
The water temperature will decrease to the outlet temperature setting of the
continuous flow water heater when the hot water from the continuous flow
water heater reaches the tap.

SAVE A SERVICE CALL
13
TEMPERATURE PRESSURE RELIEF VALVE RUNNING
Normal Operation
It is normal and desirable that this valve
allows a small quantity of water to escape
during the heating cycle. However, if it
discharges more than a couple of litres of
water in 24 hours from the Water Star, there
may be another problem.
Continuous dribble
Try gently raising the easing lever on the
relief valve for a few seconds (refer to
“Temperature Pressure Relief Valve” on
page 8). This may dislodge a small particle
of foreign matter and clear the fault.
Release the lever gently.
Steady flows for long period (often at
night)
This may indicate the mains water pressure
sometimes rises above the designed
pressure of the water heater. Ask your
installing plumber to fit a pressure limiting
valve.
Warning: Never replace the relief valve
with one of a higher pressure rating.
Heavy flows of hot water until water heater is cold - then stops until
water reheats
The water heater must be switched off at the isolating switch. Phone
Rheem Service or their nearest Accredited Service Agent to arrange for an
inspection.
EXPANSION CONTROL VALVE RUNNING
If an expansion control valve is fitted in the cold water line to the continuous
flow water heater (refer to page 22)it may discharge a small quantity of water
instead of the temperature pressure relief valve on the water heater. The
benefit is that energy is conserved as the discharged water is cooler.

SAVE A SERVICE CALL
14
HIGHER THAN EXPECTED ELECTRICITY BILLS
Should you at any time, feel your electricity account is higher than expected,
we suggest you check the following points:
Is the relief valve running excessively?
Refer to “Temperature Pressure Relief
Valve Running” on page 13.
Are you using more hot water than you
think?
Refer to “Not Enough Hot Water” on
page 12.
Is there a leaking hot water pipe,
dripping hot water tap, etc?
Even a small leak will waste a
surprising quantity of hot water and
electricity. Replace faulty tap washers,
and have your plumber rectify any
leaking pipe work.
Has there been an increase in hot water usage?
An increase in hot water usage will result in an increase in water heater
operation.
Has your tariff rate been increased by your electricity retailer since your
previous account?
IF YOU HAVE CHECKED ALL THE FOREGOING AND STILL BELIEVE YOU
NEED ASSISTANCE, CALL RHEEM SERVICE OR THEIR NEAREST
ACCREDITED SERVICE AGENT.

15
INSTALLATION
THIS WATER HEATER IS NOT SUITABLE FOR POOL HEATING
The Water Star has been designed to be installed with a continuous flow gas
water heater.
The Water Star water heater must not be installed with a continuous flow
water heater that is rated to deliver temperatures not exceeding 50°C in
accordance with AS 3498.
Warning: Temperature controllers must not be fitted to a continuous flow
water heater when a Water Star water heater is installed because water at a
temperature much higher than the controller setting can be delivered. If a Water
Star is installed to an existing continuous flow water heater installation, then all
controllers must be disconnected and removed.
The installation must comply with the requirements of AS/NZS 3500.4,
AS/NZS 3000 and all local codes and regulatory authority requirements. In New
Zealand, the installation must conform with the New Zealand Building Code.
All packaging materials must be removed from the water heater prior to its
installation.
WATER HEATER LOCATION
This water heater is suitable for either outdoor or indoor installation. Whether
located outdoor or indoor, the Water Star should be installed as close as
practicable to the continuous flow water heater and its position chosen with
safety and service in mind.
The maximum allowable length of pipe work between the Water Star and the
continuous flow water heater is:
5 metres of DN20 pipe, or
10 metres of DN15 pipe
Clearance must be allowed for servicing of the water heater. The water heater
must be accessible without the use of a ladder or scaffold. Make sure the cover
over the temperature pressure relief valve lever is accessible and the front
cover, thermostat, heating unit and temperature limiting valve can be removed
for service. You must be able to read the information on the rating plate.
Remember you may have to take the entire water heater out later for servicing.
A clear distance of at least 200 mm must be left either side of the water heater
to allow the removal of the screws securing the front cover.

INSTALLATION
16
This water heater must be installed vertically upright with the water and power
connections on the underside, pointing toward the ground or floor. The back of
the water heater can be either against a wall or supported by a frame. The
water heater must be secured to the wall or frame using suitable mounting
screws.
It is recommended to use one mounting screw at the top to firstly locate the
water heater on the wall or frame and then two at the bottom to secure the
water heater (refer to page 20 for mounting hole positions).
Remember all local authorities have regulations about putting water heaters
into roof spaces.
SAFE TRAY
It is a requirement of AS/NZS 3500.4 that for a new installation, a water heater
be installed on or over a safe tray where in the event of a leak, property may
otherwise be damaged. Construction, installation and draining of a safe tray
must comply with the abovementioned Standard.
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 22).
Model
004
Relief valve setting
1000 kPa
Expansion control valve setting*
850 kPa
Max. mains supply pressure
With expansion control valve
650 kPa
Without expansion control valve
800 kPa
* Expansion control valve not supplied with water heater
TANK WATER SUPPLY
Although the Water Star water heater does not have a minimum water supply
pressure requirement, generally a continuous flow water heater does.
If the water heater is supplied with water from a tank supply and a minimum
water supply pressure of 140 kPa at the continuous flow water heater cannot
be achieved, then a pressure pump system must be installed to allow the
continuous flow water heater to achieve its rated flow and performance. 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.

INSTALLATION
17
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.
LEGEND
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
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.

INSTALLATION
18
LEGEND
Two Temperature Zones Using a Temperature Limiting Device
Water Star with Continuous Flow Water Heater –with an ECV
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.
SATURATION INDEX
The copper cylinder of this water heater is only covered by warranty where the
saturation index (SI) of the water is greater than -1.0 and less than +0.4, or less
than +0.8 when an expansion control valve is used. The use of this water
heater with water outside of these guidelines may shorten the life of the water
heater cylinder and will void the cylinder warranty.
Refer to “Water Supplies” on page 10 and the Saturation Index chart on
page 11.
TECHNICAL DATA
Model
W8100401
W81004C1
Storage capacity
Litres
4
Thermostat setting
°C
70
Weight empty
kg
12.5
Technical date is subject to change.

INSTALLATION
19
TYPICAL INSTALLATION –OUTDOOR LOCATION
TYPICAL INSTALLATION
WATER STAR & CONTINUOUS FLOW WATER HEATER
Water Star –with a Continuous Flow Water Heater

INSTALLATION
20
DIMENSIONS
352
653 624 565
85
653
10
35
59
191
74
140
142
52
192
35 59
TPR VALVE
DRAIN
OUTLET
POWER
OUTLET
WATER
INLET
HOT
WATER
OUTLET
POWER
OUTLET
TPR VALVE
DRAIN
OUTLET
WATER
INLET
HOT
WATER
OUTLET
RHEEM WATER STAR - ELECTRIC WATER HEATER
DIMENSION DRAWING
633 565
130