Rheem 743 series 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
743 & 7431 Series Boiling Water Unit
Models 3 & 5 litre
*Model shown 743005F –Filtered model

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
Australia Only
Notice to Victorian Customers from the
Victorian Plumbing Industry Commission.
This boiling unit 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 under bench pumped water chiller and ask
for your Compliance Certificate.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
CONTENTS
About your boiling water unit.................................. 4
Operating the tap.................................................. 14
Changing the water filter....................................... 15
Save a service call................................................ 16
Installation…………………………………………....18
Electrical connection............................................. 24
Commissioning..................................................... 25
Draining the boiling water unit.............................. 25
Water supplies...................................................... 26
End of life water heater disposal .......................... 27
Rheem warranty................................................... 30
OWNER –We recommend reading pages 4 to 17.
The other pages are intended for the installer but may be of interest.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
ABOUT YOUR BOILING WATER UNIT
INTRODUCTION
Thank you for choosing our Rheem 743/7431 Series Boiling Water Unit. Please take
a few minutes to read this booklet because it contains important information about
the correct installation and operation of your Rheem Boiling Water Unit.
The Rheem Boiling Water Unit supplies both boiling water and cold water (both
supplies filtered). The tank is made from high quality copper and is designed to be
installed indoors, under sinks and in cupboards. The Rheem Boiling Water Unit is
supplied with all the required safety valving for installation (not including the isolation
valve prior to the water heater). Your Rheem Boiling Water Unit is designed to supply
boiling water to the Rheem Boiling Water Dispensing Tap. As an option, your Rheem
Boiling Water Unit can also be combined with a Rheem Water Chiller for filtered
chilled water.
WARNING
This boiling water unit is only intended to be operated by persons who have the
experience or the knowledge and the capabilities to do so. This boiling water unit 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 boiling water unit. Rheem recommend the use of the
safety function allowing only two finger operation (see page 14).
This boiling water unit uses 230-240V AC electrical power for operation of the control
systems and the electrically operated components. The removal of the jacket will
expose 230-240V wiring. The jacket must only be removed by an authorised or
qualified person.
HOW HOT SHOULD THE WATER BE?
The system controls will operate to maintain a default water temperature of near
boiling point within the boiling unit. This can be adjusted from 70-99°C.
SAFETY
The Rheem Boiling Water Unit is supplied with over temperature cut-outs on the
water heating element to prevent element burn out in the event of control failure.
The Rheem Boiling Water Unit is constructed with an integral safe tray with automatic
shut off device that complies with ATS 5200.476. A safe tray and/ or safe waste are
not required for installation.
If the electrical supply cord to the water heater is damaged, it must be replaced by an
authorised person in order to avoid becoming a hazard. Phone your nearest Rheem
Service Department or Rheem Service Centre to arrange for an inspection.
For extra electrical protection against power surges and spikes it is recommended
that a surge protector is installed prior to the boiling water unit.
WARNING:
The Rheem warranty may not cover faults if any of the installed safety devices
are tampered with.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
HOW YOUR BOILING WATER UNIT WORKS
TO TURN OFF THE BOILING WATER UNIT
The boiling water unit is supplied with a programmable timer. We recommend the
timer is used to conserve energy.
If it is necessary to turn off the boiling water unit:
Switch off the electrical supply at the isolating switch to the boiling water unit.
Close the cold water isolation valve on the supply to the boiling water unit.
TO TURN ON THE BOILING WATER UNIT
Open the cold water isolation valve fully on the cold water supply to the boiling
water unit.
Switch on the electrical supply at the isolating switch to the boiling water unit.
Note: The boiling water unit may not appear to turn on immediately when it is first switched
on, as the electronic controller will automatically check the system prior to allowing
water into the boiling water unit (this could take up to 10 seconds).
On initial start up, this boiling water unit automatically runs through a set-up cycle to
detect the boiling point of water. During this cycle, steam will discharge from the vent
pipe several times for a short time. This set-up cycle will take up to 18 minutes, and
when completed (once boiling point is determined) the unit will commence
incremental filling. It is important NOT to operate the tap during the set-up cycle
because it may affect the operating temperature of the unit.
IS THIS BOILING WATER UNIT INSTALLED CORRECTLY?
Installation requirements are shown under Installation (on page 19).
The boiling water unit must be installed:
by a qualified person, and
in accordance with the installation instructions, and
in compliance with Standards AS/NZS 3500.4, AS/NZS 3000 and all local
codes and regulatory authority requirements.
In New Zealand, the installation must also conform to Clause G12 of the New Zealand Building Code
DOES THE WATER QUALITY AFFECT THE BOILING WATER UNIT?
The boiling water unit is suitable for most public water supplies, however some water
qualities may have detrimental effects on the boiling water unit and fittings. If you are
in a known bad water area you must first read Water Supplies on page 26. If you
are not sure, have your water quality checked against the conditions described on
page 26.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
HOW YOUR BOILING WATER UNIT WORKS
HOW LONG WILL THE BOILING WATER UNIT LAST?
There are a number of factors that will affect the length of service the boiling water
unit will provide. These include the water quality, the water usage pattern etc.
However, your boiling water unit is supported by a comprehensive warranty (refer
“Warranty” on page 30). The boiling water unit is designed to operate using mains
water pressure by connecting directly to the mains water supply. If the mains supply
pressure in your area exceeds 1000kPa a secondary pressure limiting valve must be
fitted. The water supply pressure is recommended to be greater than 350kPa for the
Rheem boiling water unit’s optimum performance. Water pressure lower than 350kPa
will reduce the performance of the boiling water unit (and water chiller if installed). A
supply pressure as low as 100kPA can be used, however cold water delivery will be
reduced.
PRECAUTIONS
The boiling water unit must be maintained in accordance with the Owner’s Guide and
Installation Instructions.
If this boiling water unit is to be used where an uninterrupted boiling water supply is
necessary for your application or business you should ensure that you have back up
redundancy within the building. This should ensure the continuity of boiling water
supply in the event that this boiling water unit were to become inoperable for any
reason. We recommend you seek advice from your plumber or specifier about your
needs and building back up redundancy.
BOILING WATER
The Rheem boiling water unit is electronically controlled to obtain the maximum
performance, and incorporates further safety devices to prevent over temperature
and over filling.
ELECTRONIC CONTROLLER & TIMER
Your Rheem boiling water unit incorporates smart heating software and an electronic
timer to obtain the best efficiency for the energy used. The electronic timer allows the
user to program when the unit is on or off and when the sleep mode activates to save
energy. Also the unit has the ability to indicate and diagnose any system faults that
occur. (Refer “Setting the Timer” on page 8).
ENVIRONMENT
If a chiller unit is installed, at the end of the service life and prior to the chiller being
disposed of, a person qualified to work with refrigerants must recover the refrigerant
from within the sealed system. The refrigerant must not be vented to atmosphere.
Phone your nearest Rheem Service Department or Rheem Service Centre to arrange
for an inspection.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
WATER FILTER
The Rheem Boiling Water Unit incorporates an integral water filter. The water filter
improves the quality of water by filtering odours and particles. Over time the water
filter could become blocked with particles. Rheem recommends that the water filter
be changed at least every 12 months. The boiling water unit controller has an
*electronic filter counter that lets the operator know when the filter is getting close to
its recommended life. (*If activated by installer)
IMPORTANT
Rheem highly recommends that regular water filter cartridge changes are carried out
to ensure the system is performing to a high standard. If the water filter is not
regularly serviced and maintained on the recommended intervals, the water filter
cartridge can block with the trapped impurities, causing bacterial growth in the filter
media and dramatically reducing filtered water flow, affecting the operation of the
filtered boiling water unit.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
SETTING THE TIMER
Your Rheem boiling water unit is supplied with a programmable 7 day timer which
allows the unit to operate in the most efficient fashion to suit your needs. The timer
also incorporates a sleep mode which can be set to automatically shut the system
down after a set period of time of no use, i.e. 6 hours. The boiling water unit timer will
also control a Rheem chiller (if fitted). The Rheem tap features a safety lock function
requiring 2 finger operation to protect to users from unintentionally dispensing boiling
water when set in this mode (refer to page14).
Function
Mode
Description
A) Clock
N/A
Set clock time.
B) STD/AUTO
STD
BWU ‘ON’ 24 hours/7 days.
AUTO
BWU operates according to programmed
‘Set ON/OFF Times’.
C) Set ON/OFF
Times
N/A
Program ON/OFF times for AUTO mode.
D) Sleep Delay
Time
N/A
Program delay-off time from last usage
(operates in AUTO mode only).
E) Filter Life
Remaining Life
Displays remaining filter life in litres.
Filter Reset
Resets filter ‘Remaining Life’ to ‘Set Filter
Life’ setting. Utilised when replacing filter.
Set Filter Life
Program filter life start value in litres.
F) Service Menu
Error Codes
Displays alpha error codes (refer to page 11
for error codes and their meanings).
Boiling Temp
Displays the current boiling water
temperature in °C.
Chiller Temp
Displays the current chiller water
temperature in °C.
Calib. Reset
Reactivates automatic boiling point
calibration operation.
Temp Override
Manually select calibrated temp setting.
Selectable from 70 –99°C.
Software
Version
Displays Timer and Controller software
versions (top = Timer, lower = Controller).
Temp Show
ON/OFF
Enable/disable boiling water temperature
display on timer screen (in °C).
TB Treq
Displays boiling water temperatures in °C.
(TB = calibrated temp, Treq = maintained
temp).
G) Chiller Select
IMPORTANT:-
Select correct
chiller type.
AUTO
Automatically detects type of chiller unit.
No Chiller
Select if a stand alone chiller is installed.
Push Thr. Chil.
Select if a push through chiller is installed.
Pumped Chiller
Select if a pumped chiller unit is installed.
H) Chiller Temp
5°C –15°C
Set chilled water temperature.
I) Cold tap time
5s –60s
Set cold tap maximum on time.
J) Hot tap time
5s –20s
Set hot tap maximum on time.
K) Key lock
Enable/disable key lock function to prevent tampering with
timer settings.
* ON/OFF and Sleep Delay times operate in AUTO Mode.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
To select a Timer Mode
Press the (Prog) button until the desired mode is displayed on the screen. Press the
(Accept) button to confirm selection. Pressing (Cancel) button at any time returns
the unit to the main menu. Any functions previously accepted will be retained.
Note: The display will revert back to main menu from any mode if a button has not
been pressed for 1 minute.
A) Setting the clock
Select the clock mode
(Prog>Clock>Accept)
Display Shows: “Set Clock Day”.
Press the (UP) button until the desired day appears on the screen and press the
(Accept) button to confirm selection.
Display Shows: “Set Clock HOUR”
Press the (UP) button until the desired hour (24 Hour Time) appears flashing on the
screen and press the (Accept) button to confirm selection.
Display Shows: “Set Clock MIN”
Press the (UP) button until the desired minute appears flashing on the screen.
Press the (Accept) button to confirm selection and the display reverts to the main
menu.
B) Set timer to STD/AUTO mode
Select the Timer STD/AUTO mode (Prog>Timer STD/AUTO>Accept)
Display Shows: “STD”
Pressing the (UP) button alternates “STD”/“AUTO” mode. “STD”mode means that
the unit operates 24 hours a day, “AUTO”mode means the unit operates during the
preset time periods (7am - 5.30pm, Mon - Fri) on the timer. Press the (Accept)
button to confirm selection and the display reverts to the main menu. If the timer is in
“AUTO”mode, pushing any timer key or lever on the tap will reactivate the unit. The
unit will operate normally until the next programmed “Off” time.
C) Programming set on/off times (For use in “AUTO”Mode)
Select the Timer ON/OFF mode
(Prog>Set ON/OFF times>Accept)
Note: To set the unit to be in “Off”mode for an entire day, set the “On” and “Off”
times to be the same eg: On = 0:00 Off = 0:00
Display Shows: “SUN” “7:00 –7:00” “Set ON hour”.
Press the (UP) button until the desired hour appears on the screen and press the
(Accept) button to confirm selection.
Display Shows: “SUN” “7:00 –7:00” “Set ON minute”.
Press the (UP) button until the desired minute appears on the screen and press the
(Accept) button to confirm selection.
Display Shows: “SUN” “7:00 – 7:00” “Set OFF hour”.
Press the (UP) button until the desired hour appears on the screen and press the
(Accept) button to confirm selection.
Display Shows: “SUN” “7:00 – 7:00”“Set OFF Minute”.
Press the (UP) button until the desired minute appears on the screen and press the
(Accept) button to confirm selection and advance to the next day.
Display Shows: “MON” “7:30 –17:30” “Set ON hour”.
Note: Continue with same procedure for Monday through to Saturday.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
D) Programming sleep delay time.
Select the Sleep on/off mode (Prog>Sleep DelayTime>Accept)
Display Shows: “Sleep Delay Time” “OFF”.
The Sleep Delay Function puts the unit in a standby mode after a user defined period
(1 - 6 hours). The Sleep Delay Function factory default setting is OFF. Pressing the
(UP) button increases the sleep delay time up to 6 hours. Press the (Accept) button
to confirm selection and the display reverts to the main menu. The unit will go into
“Sleep” mode if it has not been used during the “Sleep delay time” period. To exit
“Sleep”, push any timer key or lever on the tap. If you activate the Sleep Delay Timer
we recommend that you also activate the Temp Show On/Off function.
E) Filter Life
Select the Appropriate Filter Mode (Prog>Filter life>Accept)
i) Remaining Life
ii) Filter Reset
i) To Select Remaining Life mode
(Prog>Filter Life>Accept>Remaining Life)
Display Shows: “Remaining Life” “XXXX litres”
Press the (Cancel) or (Accept) button to revert back to the main menu.
ii) To Select the Filter Reset mode
(Prog> Filter Life >Accept>filter reset>Accept)
Display Shows: “Filter Reset”
Press the (Accept) button to confirm selection at which time you are prompted
“Are you sure?”. Press (Accept) once more then,
Display Shows: “Set Filter Life” “XXXX Litres”.
Pressing the (UP) button scrolls from the filter OFF selection (this turns the filter
count off if a filter is not installed with the boiling water unit) up to 12,000 litres. We
recommend a default value of 4,000 litres, until the user knows the filter will last
longer. Press the (Accept) button to confirm selection and the display reverts to
the Filter menu.
F) Accessing service menu
The service menu has seven modes to select from (refer to ‘timer functions’ on page
8). This function allows easy identification of problems occurring with the unit by the
service technicians (see details on the Error code table (page 11) for product error
codes).
Select appropriate Service Mode
i. Error Codes
ii. Boiling Temp
iii. Chiller Temp (display only)
iv. Calib Reset
v. Temp. Override
vi. Software Version
vii. Temp Show ON/OFF
viii. TB Treq

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
I. Error Codes
(Prog>Service>Accept>Error Codes)
This function allows easy identification of problems occurring with the unit by
service technicians.
Error
Code
Error
Code
Hot Thermistor O/C, S/C
A
Low Level Probe Fault
H
Cold Thermistor O/C, S/C
B
High Level Probe Fault
J
Triac S/C
C
Compressor Fault
K
Leak Detected
D
Water Heating Fault
L
Expired Filter
E
Excessive Temperature Rise
N
Calibration Time Out
G
II. For Boiling Unit Display Temp mode
(Prog>Service>Accept>Boiling Temp)
Display Shows: “XXX °C”
This function displays the current boiling water temperature.
Press the (Cancel) button to revert back to the main menu.
III. For Chiller Unit Display Temp mode
(Prog>Service>Accept>Chiller Temp)
Display Shows: “XXX °C”
This function displays the current chilled water temperature.
Press the (Cancel) button to revert back to the main menu.
IV. For Calibration Reset mode
Prog>Service>Accept>Calib.Reset>Accept)
Display Shows: “Calib. Reset”
This function recalibrates the boiling water unit to boiling point. Press the (Accept)
button to recalibrate the boiling point. Press (Accept) again at the “Are You
Sure?” prompt. Press the (Cancel) button to revert back to the Main menu. The
timer will now display “Calibrating Do Not Interrupt”. When calibration is
complete the timer display will revert back to the main menu.
V. For Temp Override mode
(Prog>Service>Accept>Temp Override>Accept)
This function allows the user to manually set the required boiling water
temperature.
Display Shows: “XX °C”
Press the (UP) button until the desired temperature is shown (range is from 70°C
to 99°C). Press the (Accept) button to activate the selection, then the words “Are
You Sure?”will flash on the screen. Press the (Accept) button to confirm your
selection. The words “Calibrating Do Not Interrupt” may appear for a short
period, this is the unit is checking that it is able to reach the temperature you
require. Once the unit has finished checking, the screen will return to normal.
VI. To Display the Software Version
(Prog>Service>Accept>Software Version>Accept)
This displays both the Timer and Controller software versions. The top digits
relate to the timer software version, and the lower digits relate to the controller
software version.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
VII. Temp Show On/Off (Prog>Service>Accept>TempShow ON/OFF)
Display Shows: “Hot XX°C” (no chiller installed), or “Hot XX Cold XX” (with
Rheem chiller installed).
This function allows the temperature of the water within the boiling water unit (and
chiller if installed) to be displayed permanently on the timer display. Press the (UP)
button to switch modes between ON and OFF.
Press (Accept) to confirm, and the display reverts back to the service menu.
VIII. TB Treq
(Prog>Service>Accept>TB Treq
This function allows the user to see what temperature the boiling water unit is
calibrated to and the temperature the boiling water is maintained to.
The figure below the letters TB is the units’ calibrated temperature, the figure
below the letters Treq is the temperature the boiling water is maintained to.
G) CHILLER SELECTION
Select Appropriate Chiller Mode (Prog>Chiller Selection>Accept)
i. Auto
ii. No Chiller
iii. Push Thru. Chil
iv. Pumped Chiller
i) To Select Auto mode
(Prog>Chiller Selection>Accept>Auto)
This allows the unit to automatically detect if any chiller is attached to the unit.
Press (Accept) to confirm and the display reverts back to the service menu.
ii) To Select No Chiller mode
(Prog>Chiller Selection>Accept>No Chiller)
This allows the user to attach a stand alone chiller to the boiling water unit. By
activating the ‘No Chiller mode’, the cold lever will deliver filtered tap temp water to
either a separate chiller or straight to tap.
Press (Accept) to confirm and the display reverts back to the service menu.
iii) To Select Push Thru. Chil mode
(Prog>Chiller Selection>Accept>Push Thru. Chil)
If the unit incorrectly senses the appropriate chiller, the user can manually set the
unit to a Push Through Chiller.
Press (Accept) to confirm and the display reverts back to the service menu.
iv) To Select Pumped Chiller mode
(Prog>Chiller Selection>Accept>Pumped Chiller)
If the unit incorrectly senses the appropriate chiller, the user can manually set the
unit to a Pumped Chiller.
Press (Accept) to confirm and the display reverts back to the service menu.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
H) CHILLER TEMP
Select Appropriate Chiller Temperature (Prog>Chiller temp>Accept)
Display Shows: “XX °C”
Press the (UP) button to scroll from 5°C to 15°C.
Press (Accept) to confirm and the display reverts back to the service menu.
I) COLD TAP TIME
Select Appropriate Cold Tap Time (Prog>Cold Tap Time>Accept)
Display Shows: “XXs”
This allows the user to define the maximum volume of water that can be drawn from
the unit in one pour.
Press the (UP) button to scroll from 5s to 60s.
Press (Accept) to confirm and the display reverts back to the service menu.
J) HOT TAP TIME
Select Appropriate Hot Tap Time (Prog>Hot Tap Time>Accept)
Display Shows: “XXs”
This allows the user to define the maximum volume of water that can be drawn from
the unit in one tap activation.
Press the (UP) button to scroll from 5s to 20s.
Press (Accept) to confirm and the display reverts back to the service menu.
K) KEY LOCK
Select Key Lock (Prog>Key Lock)
Display Shows: “Key Lock”
This allows the user to lock the timer keys to prevent tampering.
Press the (Accept) button to confirm selection and the display will now show “Key
Lock Enable” Press the (Accept) button again to reconfirm selection and the display
reverts to the main menu.
To unlock the Key Lock function, push the “Prog” and “Up” buttons simultaneously
for 10 seconds.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
OPERATING THE TAP
The Rheem tap is used to dispense filtered boiling water and filtered cold or chilled
water. There are currently two tap styles available, the 743 Series (Aqua) and the
7431 Series (Azure). Both taps have identical functionality. The Rheem tap has 2
levers (hot and cold), a safety lock button (child safety lock) and 3 LED’s (orange, red
and green). When operating the tap, unless adjusted it will automatically stop the
water delivery every 20 seconds. This is to prevent the tap being turned on
permanently.
TAP LEVERS
The Rheem Tap has two levers. The hot lever has a red insert, and the cold has a
blue insert.
To operate the levers you can:
a) Pull the lever up to allow for hands free filling of large vessels, or
b) Push and hold the lever down for cup fills.
SAFETY LOCK BUTTON
The tap also incorporates a safety lock feature. To activate and de-activate the safety
lock you must push the safety lock button down for 5 seconds. When the safety lock
is activated, the word SAFETY will light up in red on the top of the tap. To operate the
boiling water tap when the safety lock is on, press and hold the safety button whilst
activating the hot lever (indicated by the red insert). It is not necessary to hold the
safety button for cold water delivery.
TAP LED’S
The Rheem tap contains 3 LED’s. The LED’s are located by the safety lock button.
The green LED (heating or ready) indicates the status of the boiling water unit
temperature. If the green LED is flashing, the boiling unit is filling and heating.
Water may be drawn from the hot lever, however the quantity available may be
limited and the water temperature below the set temperature. If the green LED is
solid it means the unit is at the required temperature.
The orange LED (filter) if flashing, indicates the water filter (if installed) should be
replaced. See Setting the Timer, Section E on page 10 for resetting the filter timer.
The red LED (Illuminates the word ‘SAFETY’)if on, indicates the safety button has
been activated. See above for instructions on how to set safety mode.
Also refer to ‘Save A Service Call’on page 16 for tap error codes.
743 Aqua
7431 Azure

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
CHANGING THE WATER FILTER
IF A WATER CHILLER IS CONNECTED PROGRESS THROUGH ALL STEPS
IF A WATER CHILLER IS NOT CONNECTED DO STEPS 1, 2, 4, 5, 6, 7, 9, 10 & 11
Step 1: Isolate the water supply to the boiling water unit then activate the cold lever to
relieve the water pressure.
Step 2: Isolate the boiling water unit from the electricity supply.
Step 3: Disconnect all electrical chiller connections to the boiling water unit
Step 4: Unlock the filter from the housing by rotating the filter body a quarter turn clockwise.
Step 5: Remove filter by lowering from housing. Ensure that minimal water is spilled within
the boiling unit when removing filter. We recommend a clean rag is placed below the
filter in the unit to ensure no water is left in the base of the unit.
Step 6:Prepare new filter by removing the plastic wrap and taking off the top plastic cover
covering the inlet to the filter.
Step 7: Replace water filter by reversing steps 4 and 5.
Step 8: Disconnect chilled water outlet pipe from the water chiller (if connected) and connect
it to the chilled water supply connector on boiling unit.
Step 9: Turn water on to the boiling water unit.
Step 10:Turn the electricity to the unit back on.
Step 11:Flush the new water filter by activating the cold button on the tap for a minimum of 5
minutes (note: the continuous draw off time can be increased to 1 minute intervals
(see Section I page 12)
Step 12:Once flushing is complete, put the chilled water outlet pipe back onto the outlet
connection on the chiller, and connect the chiller inlet supply pipe back onto the
chilled water supply connector.
Step 13:Reconnect all electrical connections from the chiller back onto the boiling water unit.
Step 14:Check unit is functioning correctly and dispose of the old filter cartridge responsibly.
Step 5: Remove filter by lowering from housing.
Ensure that minimal water is spilled within the
boiling unit when removing filter.

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
SAVE A SERVICE CALL.
Check the items below before making a service call. You will be charged for Rheem
attending to any condition or fault that is not related to manufacture or failure of a part
NOT ENOUGH (OR NO) BOILING WATER
Is the electricity switched on?
Inspect the wall power socket to see if it is switched on. Also check the fuse or circuit
breaker at the switchboard to see if it is blown or tripped.
Is the timer in the off period?
If the unit has been in an off period and the water is below the optimum delivery
temperature, the green LED flashes when the unit is woken. To ‘wake’ the unit press
the hot lever on the boiling water tap or any timer button. The unit will activate the
element and reheat the water to the set temperature.
Is the leak sensor detecting there is water with the unit?
There is a leak sensor in the boiling water unit that detects if there is water in the safe
tray (error code D displayed on the timer screen, see page 11 section F,1). Phone
your nearest Rheem Service Department or Rheem Service Centre to arrange for an
inspection.
Are all Tap LED’s Flashing? (safety & orange then green)
The tap lever was pushed down too slowly. Reset the tap button to the OFF position
and fully activate tap lever. If the LED’s continue flashing a fault has occurred with
the tap. Phone Rheem Service or a Rheem Service Centre to arrange for an
inspection.
Has there been heavy use?
Heavy boiling water usage can result in the tank level dropping below the low level
probe. In this situation the boiling water pump is deactivated. The green LED on the
tap may also flash due to insufficient temperature as the tank refills. This is normal
operation. Wait for a time period to allow the tank to refill and reheat. The green LED
will stop flashing as the water heats up to the usable temperature.
WATER NOT HOT ENOUGH?
Heavy usage
You may find that due to heavy boiling water usage the boiling water volume required
may be less than what is available. This is due to insufficient recovery time being
allowed. If the available water temperature is too low the Green LED will flash until
usable temperature is reached.
High altitude
The boiling water unit is fitted with automatic altitude calibration to prevent the water
from continually boiling, which is not energy efficient. Different altitudes cause water
to boil at different temperatures. If you believe the water temperature is not hot
enough, recalibrate the unit (see page 11 section 4).

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Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
SAVE A SERVICE CALL
HIGH ELECTRICITY BILLS
Should you at any time, feel your electricity account is too high, we suggest you
check the following points:
This water heater has an ON/ OFF automatic timer and a sleep mode. Check to see
if these features have been activated. Refer “Setting the Timer” on page 8.
UNIT WILL NOT SWITCH OFF
The electronic timer will only switch the unit on or off when it is in “Auto” mode (See
section B on page 9) otherwise the unit will operate 24 hours a day 7 days a week.
NO WATER COMING OUT OF THE TAP
There may have been a large draw off prior. Wait for the unit to fill enough for you to
get water out. If water will still not come out of the tap check the timer display. If there
is an error message call the Rheem Service Department or a Rheem Service Centre
for a service call.
POOR CHILLED WATER DELIVERY
For Rheem 290254 and 290255 series push through and 290250 and 290251 series
pumped water chillers the information below will aide in fault detection. For
installations using third party chillers please refer to the chiller manufacturers
instructions for further information.
Low supply pressure
If the water supply pressure is below 350kPa, lower than acceptable delivery rates
may occur.
Blocked filter
Water flow rate will diminish over time as the filter removes particles from the water
supply. To change the filter, refer to page 15 or if assistance is required contact
Rheem service department or Rheem service centre.
The electronic timer has a filter life counter. The tap will indicate when the filter
should be changed by flashing the orange LED on the tap.
TIMER CLOCK HAS RESET AND/OR LOST PROGRAMS
This unit has a factory fitted battery to retain settings in the event of a power cut or if
the unit is turned off. The expected life of this battery is many years, even if power
cuts are frequent. If the battery has gone flat or is faulty for any reason, the unit will
operate as normal, but may lose the clock and timer program settings in a power cut.
It will revert to STD mode rather than AUTO but will still operate normally in
continuous 24/7 mode. If the battery needs replacing, contact Rheem Service
Department or a Rheem Service Centre.
IF YOU HAVE CHECKED ALL THE ABOVE AND STILL BELIEVE YOU NEED
ASSISTANCE, CALL THE RHEEM SERVICE DEPARTMENT OR RHEEM
SERVICE CENTRE.

18
Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
INSTALLATION
THIS BOILING WATER UNIT IS FOR INDOOR INSTALLATON ONLY.
BOILING WATER UNIT LOCATION
The boiling water unit must be installed within 1 metre of the Rheem tap. Ensure that
the jackets’ air vents are clear of obstructions at all times. The boiling water unit is
designed to fit under a standard sink (internal cupboard depth of 550mm). The boiling
water unit should be positioned with the timer display facing the front of the cupboard
or space for easy viewing.
Clearance must be allowed for servicing of the boiling water unit. The installer must
leave at least 50mm clearance on sides that have vents to allow air flow through the
boiling water unit.
You must be able to read the information on the rating plate. Remember you may
have to remove the entire boiling unit and chiller for servicing.
The installation must comply with the requirements of AS/NZS3500, AS/NZS3000
and water supply by-laws, relevant local authority by-laws, codes (e.g. Building
Code) and regulatory authority requirements. In New Zealand, the installation must
conform to the New Zealand Building Code.
The water heater must not be installed in an area with a corrosive atmosphere where
chemicals are stored or where aerosol propellants are released. Remember the air
may be safe to breathe, but the chemicals may attack the materials used in the
construction of the boiling water unit, or adversely affect the operation of the boiling
water unit.

19
Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
INSTALLATION
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.
Model
743 series
Max. mains water pressure
pressure
1000kPa
Min. mains water pressure
pressure
350kPa
Max. mains water temperature
temperature
38°C
Min. mains water temperature
2°C
TANK WATER SUPPLY
If the boiling water unit is supplied with water from a tank supply and a minimum
water supply pressure of 350kPa at the boiling water unit cannot be achieved, then a
pressure pump system must be installed to allow the boiling water unit to operate.
The cold water line from the supply tank should be adequately sized and fitted with a
full flow gate valve or ball valve, care must be taken to prevent water hammer
occurring between the pump and boiling water unit. Failure to comply can void the
warranty.
THREADED CONNECTION SIZE
Cold water inlet connection: RP½ / 15mm
All plumbing work must be carried out by a qualified person and in accordance with
AS/NZS 3500.4 and local authority requirements.
INSTALLATION SEQUENCE
The installation sequence should be as follows:
Connect cold water mains supply
Fit Chiller / Fan units
Install boiling/chilled water tap
Connect boiling water chilled/filtered water and vent tubes

20
Rheem New Zealand Ltd 743 Series BWU Document #: 318489B
INSTALLATION
Typical under-bench installation
Mains Water Connection
COLD WATER INLET
The pipe work must be clear of foreign matter before connection and purged before
attempting to operate the boiling water unit. All olive compression fittings must use
brass or copper olives. Use thread sealing tape or approved thread sealant on all
fittings.
It is mandatory for a union isolation valve to be fitted on the cold water supply
line to the boiling water unit for removal for servicing.
The internal pressure limiting valve incorporates a dual non-return valve
therefore extra non-return valves are not required for installation.
A good quality Watermarked flexible inlet pipe must be installed between the union
isolation valve and inlet connector on the unit, suitably long enough to allow the
boiling water unit to be moved to the front of the cupboard so as to overhang the
cupboard front by 50mm.
Note: A non-Watermarked flexible inlet pipe will deteriorate and affect the water
quality entering the unit. Ensure that all flexible inlet pipes are Watermarked and
hydrolysis resistant. Note this is mandatory in Australia.
Connect the cold water supply to the fitting marked “Inlet” on the boiling water unit.
Inlet Water Pipe
Inlet Water
Connection ½”BSPT