AquaMAX EM50 Series Technical Document

This water heater must be installed and serviced by a qualified person.
Please leave this guide with the householder.
Owner’s Guide
and
Installation Instructions
Domestic Mains Pressure
Electric Storage Water Heater
EM50 and E80 to E400 Series

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Warning: Upon completion of the installation and commissioning of the
water heater, leave this guide with the householder or responsible officer.
DO NOT leave this guide inside the cover of the water heater, as it may
interfere with the safe operation of the water heater or ignite when the
water heater is turned on.
Patents
This water heater may be protected by one or more patents or registered
designs in the name of Aquamax Australia Pty Ltd.
Trademarks
®
Registered trademark of Aquamax Australia Pty Ltd.
TM
Trademark of Aquamax Australia Pty Ltd.

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CONTENTS
Householder: Read the section “About Your Water Heater” (pages 3 to
16). The “Installation” section is intended for the installer but may be of
interest.
ABOUT YOUR WATER HEATER ................................................................3
Model Type................................................................................................3
Turning On the Water Heater....................................................................6
Shut Down Procedure ...............................................................................6
Temperature Adjustment...........................................................................6
Other Important Information ......................................................................7
Periodic Maintenance................................................................................8
Water Chemistry......................................................................................11
Troubleshooting ......................................................................................14
INSTALLATION ..........................................................................................16
Installation Overview ...............................................................................16
Water Supplies ........................................................................................18
Plumbing & Plumbing Diagrams .............................................................18
Plumbing Connections.........................................................................18
Two Temperature Zones Using a Temperature Limiting Device.........23
Circulated Hot Water Flow & Return Systems ....................................24
Electrical & Electrical Connections..........................................................25
Thermostat Adjustment .......................................................................26
Commissioning........................................................................................27
Draining the Water Heater ......................................................................28
Dimensions & Technical Data .................................................................29
WARRANTY ...............................................................................................31

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ABOUT YOUR WATER HEATER
Product Application
This water heater is designed for use in a single family domestic dwelling
for the purpose of heating potable water. Its use in an application other
than this may shorten its life.
Model Type
Aquamax
®
electric storage water heaters are available with either a single
heating unit or with twin heating units (refer to “Single Element Model” and
“Twin Element Model” on page 4). The water heater can be installed in an
indoor or outdoor position and is not to be used as a pool heater.
Water is stored in a vitreous enamel lined steel cylinder and is heated by
an electric immersion heating unit (element). The thermostat controls water
temperature whilst automatic safety controls fitted to the water heater
provide safe and efficient operation.
Model Selection Chart
50 Litre
80 Litre
125 Litre
160 Litre
250 Litre
315 Litre
400 Litre
EM50S36
E80S18 E125S18 E160S18 E250S24 E315S36 E400S36
EM50S18L E80S24 E125S24 E160S24 E250S36 E315S48 E400S48
EM50S24L E80S36 E125S36 E160S36 E250S48 E315T36 E400T36
E125S48 E160S48 E250T36 E315T48 E400T48
E160T24 E250T48
E160T36
E160T48
E160S18X
E160S24X
E160S36X
E160S48X
Note: All models can be supplied with a ‘Hard Water Anode’. These models
have the suffix ‘HWA’ at the end of the model number.
Legend
E
or EM
(50L Only)
Electric Series 240V AC, 50Hz
50, 80
, ,...
400
Rated hot water delivery in Litres
S
Single bottom element
T
Twin element *
18, 24, 36, 48
Element wattage (1800W, 2400W, 3600W, 4800W)
X
Special short version
L
Fitted with a 240V AC, 10A power supply lead & plug
* Both elements are of the same wattage and are wired for non simultaneous
operation.

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Single Element Model
This type of water heater has one heating unit with its own
thermostat. The heating unit is at the base of the water
heater and the unit can be connected to a continuous or
off-peak electricity supply. The thermostat is adjustable
between 60 ~ 75°C with a factory setting of 65°C (70°C for
EM50 models).
•Continuous electricity supply
This type of connection is suited to where the storage
capacity is less than the normal daily usage.
•Off-Peak electricity supply
This type of connection will only allow heating to occur
during set hours. A volume of water sufficient for the
day’s total use is heated and stored. This type of
heating will be more economical due to reduced tariffs
by the electricity authority.
Twin Element Model
This type of water heater has two heating units, each with its own
thermostat. One heating unit is at the base of the water heater and the
other near the top. The lower thermostat is adjustable between 60 ~ 75°C
(factory setting 70°C) whilst the top thermostat is fixed at 60°C.
•Bottom heating unit (main heating unit)
During normal operation this heating unit supplies all
the hot water.
•Top heating unit (booster)
This heating unit only operates during periods of high
demand to provide an additional supply of heated
water.
•Electrical connection
The two heating units are wired for non simultaneous
operation so that only one heating unit can operate at a
time. The bottom heating unit is usually connected to an
Off-Peak (overnight) or time controlled electricity supply
and the top heating unit to a continuous supply. Some
electricity suppliers allow both heating units to be
metered at the Off-Peak or controlled tariff.
Note: Power must be available to the top heating unit circuit at all times for
this water heater to operate as designed.

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Mains Pressure Operation
This 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 in “Mains Water Supply” on page 18, a pressure
limiting valve must be fitted. The supply pressure should be greater than
350 kPa for true mains pressure operation to be achieved.
Hot Water Temperature
This water heater features an adjustable thermostat which can be set to the
most suitable temperature for your hot water needs. Refer to “Temperature
Adjustment” on page 6.
To meet the requirements of the National Plumbing Standard and to inhibit
the growth of legionella bacteria, the temperature of the stored water must
not be below 60°C which is the minimum thermostat setting of the water
heater. This is also the top heating unit thermostat setting on a twin
element model (the top heating unit thermostat is non adjustable).
The maximum main heating unit thermostat setting is 75°C with a factory
setting of 70°C for EM50 and twin element models (top element fixed at
60°C) and a factory setting of 65°C for all other single element models.
High Hot Water Temperature Increases the Risk of Scald Injury
Warning: This water heater can deliver water at temperatures which
can cause scalding. Always 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 a scald injury. Aquamax recommends
monthly temperature checks to ensure the appropriate temperature is
maintained within the hot water heater.
Aquamax recommends, and it may also be required by regulations, that a
secondary device such as an approved temperature limiting device or anti-
scald water shut off valve be fitted into the hot water pipe work to the
bathroom(s) and ensuite(s) if persons living in the house require additional
safety protection from potential scalding. This will keep the hot water supply
temperature to the bathroom(s) and ensuite(s) below 50°C which will
reduce the risk of scald injury whilst still allowing hotter water (60°C+) to the
kitchen and laundry.
For new hot water installations, all sanitary outlet fixtures used primarily for
personal hygiene purpose must deliver hot water not exceeding 50°C. This
temperature limit is not mandatory for kitchen sinks and laundry tubs and
the preferable temperature setting for these outlets should be 60°C.

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To minimise scalding, especially for those people in high scald risk
categories i.e. young children, people with potentially incapacitating
medical conditions, elderly people etc, this water heater must be installed in
accordance with AS/NZS 3500.4.
This appliance is not intended for use by persons (including children) with
reduced physical, sensory or mental capabilities, or lack of experience and
knowledge, unless they have been given supervision or instruction
concerning use of the appliance by a person responsible for their safety.
Children should be supervised to ensure that they do not play with the
appliance.
For early childhood centres, primary and secondary schools, nursing
homes or similar facilities for young, aged, sick or disabled persons, please
consult your local health authority for the correct temperature setting.
Turning On the Water Heater
Warning: The water heater can only be switched on upon completion
of the installation by a qualified person.
To turn on the water heater:
1. Fully open the cold water isolation valve at the cold water inlet to the
water heater.
2. Switch on the circuit breaker or isolator marked “Hot Water” or “Water
Heater” at the switchboard.
Shut Down Procedure
If it is necessary to turn off the water heater:
1. Switch off the circuit breaker or isolator marked “Hot Water” or “Water
Heater” at the switchboard or switch off the water heater isolating
switch if one is installed.
2. Close the cold water isolation valve at the cold water inlet to the water
heater.
Temperature Adjustment
The thermostat automatically controls the electricity supply to the heating
unit so that a constant temperature is maintained within the storage
cylinder. The thermostat is fully automatic and power is only used when the
water in the storage cylinder requires heating. There is no need to switch
the water heater off when it is not in use, except when you are going away
for an extended period.

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Warning: The thermostat and its protective over temperature cut out
are mounted inside the front cover(s) of the water heater. The removal of
the front cover(s) will expose 240V wiring. Access covers must only be
removed by an electrician or qualified person.
Warning: Thermostat temperature adjustment must only be performed
by an electrician or qualified person.
Warning: Children should be supervised to ensure they do not interfere
with the water heater.
Other Important Information
Going Away?
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 either the switchboard or isolating switch (if fitted).
Note: When switched back on, the water heater may take 2 ~ 6 hours to
reheat depending upon element and water heater size. If connected to an
off peak system, hot water may not be available until the following morning.
Safety
This water heater is supplied with a thermostat, an over temperature and
energy cut out, and a combination pressure temperature relief valve. These
devices must not be tampered with or removed. The water heater must not
be operated unless each of these devices are fitted and are in working
order.
The Aquamax warranty may not cover faults if relief valves or other safety
devices are tampered with or if the installation is not in accordance with
these instructions.
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. These instructions must be read in conjunction with
all other instructions affixed to the appliance.
Warning: For models with a power supply lead and plug; take care not
to touch the power plug with wet hands.
Warning: For models with a power supply lead and plug; if the power
lead is damaged, it must be replaced by an electrician or qualified person in
order to avoid a hazard.

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How Long Will the Water Heater Last
The water heater is supported by a manufacturer’s warranty (refer to page
31). There are a number of factors that will affect the length of service the
water heater will provide. These include but are not limited to the water
chemistry, the water pressure, the water temperature (inlet and outlet) and
the water usage pattern.
Precautions
Where damage to property can occur in the event of the water heater
leaking, the water heater must be installed in a safe tray. Construction,
installation and draining of a safe tray must comply with AS/NZS 3500.4
and all local codes and regulatory authority requirements.
The water heater must be maintained in accordance with the Owner’s
Guide and Installation Instructions. Refer to “Periodic Maintenance” below.
If this water heater is to be used where an uninterrupted hot water supply is
necessary for your application or business, you should ensure that you
have back up redundancy within the hot water system design. This should
ensure the continuity of hot water supply in the event that this water heater
was to become inoperable for any reason. We recommend you seek advice
from your plumber or specifier about your needs and building back up
redundancy into your hot water supply system.
Periodic Maintenance
Minor Six Monthly Maintenance
It is recommended minor maintenance be performed every six months by
the dwelling occupant.
Warning: Exercise care when operating easing levers as water
discharged from the water heater may be of a very high temperature.
Minor maintenance actions:
1. Operate easing lever on pressure temperature relief valve (refer to
“Pressure Temperature Relief Valve” on page 9).
2. Operate easing lever on expansion control valve (if ECV fitted) (refer
to “Expansion Control Valve” on page 10).
3. If an overflow tray is installed, check to ensure the overflow tray drain
pipe is not blocked.

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Major Five (5) Year Service
It is recommended a major five (5) year service be conducted on the water
heater. Servicing must be performed by a qualified person. Phone
Aquamax Service or their nearest Accredited Service Agent.
Note: The five (5) year service and routine replacement of any
components, such as the anode and relief valve(s), are not included in the
Aquamax warranty. A charge will be made for this work.
Major five (5) year service actions:
1. Replace pressure temperature relief valve.
2. Inspect and flush expansion control valve (if ECV fitted) and replace
expansion control valve if required.
3. Inspect anode and replace anode if required. If the anode is not
replaced, it should be replaced within three (3) years of this service.
Refer to “Anode” on page 10.
4. Check electric heating unit for excessive calcium build up or corrosion
and replace heating unit if required.
5. Visually check water heater for any potential problems.
6. Inspect all plumbing and electrical connections.
Note: The water heater will need to be drained during this service and will
take some time to reheat the water after servicing has been completed.
Depending upon the power supply connection, hot water may not be
available until the next day.
Pressure Temperature Relief Valve (PTR valve)
The PTR valve is near the top of the water heater and is essential for safe
water heater operation. It is possible for the PTR 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 PTR valve and its drain line may
indicate a problem with the water heater (refer to “Pressure Temperature
Relief Valve Running” on page 15).
Warning: Never block the outlet of the PTR valve
or its drain line for any reason.
Operate the easing lever on the PTR valve once every
six months. It is very important you raise and lower
the lever gently.

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Warning: Exercise care when operating easing lever as water
discharged from the water heater may be of a very high temperature.
Warning: Exercise care to avoid any splashing of water, as water
discharged from the drain line will be hot. Stand clear of the drain line’s
point of discharge when operating the valve’s lever.
Danger: Failure to perform this procedure may result in the water
heater storage cylinder failing.
If water does not flow freely from the drain line when the lever is lifted, then
the water heater must be checked. Phone Aquamax Service or their
nearest Accredited Service Agent to arrange for an inspection.
The pressure temperature relief valve should be replaced at intervals not
exceeding five (5) years, or more frequently in areas where there is a high
incidence of water deposits (refer to “Water Chemistry” on page 11).
Expansion Control Valve (ECV)
In many areas, including South Australia, Western Australia and scaling
water areas, an ECV is fitted to the cold water supply line to the water
heater (refer to the “Cold Water Supply Plumbing Arrangement” diagram on
page 19). The ECV may discharge a small quantity of water from its drain
line during the heating period instead of the PTR valve on the water heater.
Operate the easing lever on the expansion control valve once every six
months. It is very important that you raise and lower the lever gently.
The expansion control valve should be checked for performance or
replaced at intervals not exceeding five (5) years, or more frequently in
areas where there is a high incidence of water deposits (refer to “Water
Chemistry” on page 11).
Anode
The anode installed in your water heater has been designed to slowly
dissipate whilst protecting the storage cylinder. If the hot water heater is not
used for two (2) weeks or more, a quantity of hydrogen gas, which is highly
flammable, may accumulate in the water heater. To dissipate this gas
safely, it is recommended that a hot tap be turned on for several minutes or
until discharge of gas ceases. Use a sink, basin, or bath outlet, but not a
dishwasher, clothes washer or other appliance. During this procedure,
there must be no smoking, open flame, or any electrical appliances
operating nearby. If hydrogen is discharged through the tap, it will probably
make an unusual sound similar to air escaping.

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The life of the storage cylinder may be extended by arranging a qualified
person to periodically inspect the anode and replace if required. If the
anode is not replaced during a five (5) year service (refer to “Major Five (5)
Year Service” on page 9) then the maximum time after installation when the
anode should be replaced for this electric water heater is eight (8) years.
For water supplies which are either softened, desalinated or where the
water supply may alternate between a water tank and a reticulated public
supply or another supply, it is recommended the anode be replaced within
five (5) years of installation.
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 the water
heater storage cylinder, pressure temperature relief valve and 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 the Aquamax warranty to apply.
Water Chemistry
This water heater must be installed in accordance with this advice to
be covered by the Aquamax 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 Aquamax warranty to apply.
Total Dissolved Solids (TDS)
Some water analysis reports may state the conductivity of the water rather
than the level of total dissolved solids. Conductivity, measured in
microsiemens per centimetre (µS/cm), is directly proportional to the TDS
content of the water. TDS, in mg/Litre, is approximately 70% of the
conductivity in µS/cm.
The Aquamax warranty will not cover resultant faults to the storage cylinder
if this water heater is connected at anytime to a water supply where the
TDS content of the water exceeds 600 mg/Litre. In locations where the

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water supply TDS exceeds 600 mg/Litre, the magnesium alloy anode
(supplied as standard, cap colour code ‘Black’) should be replaced with an
aluminium alloy anode (cap colour code ‘Blue’). For more information refer
to “Water Chemistry & Anode Type” on page 12.
In locations where TDS approaches 600 mg/Litre, e.g. due to sediment, we
strongly recommend fitting an appropriate filter to ensure water entering or
in the water heater does not exceed this level at any time i.e. due to
sediment build up.
Water Chemistry & Anode Type
Aquamax water heaters are designed to suit the water conditions of most
metropolitan supplies, where the Total Dissolved Solids (TDS) content of
the supply is less than 600 mg/Litre. For use in regions where the water
supply TDS exceeds 600 mg/Litre, the magnesium alloy anode (supplied
as standard, cap colour code ‘Black’) may become excessively reactive.
For safety reasons and the longevity of the anode, the magnesium anode
should be replaced with an aluminium alloy anode (cap colour code ‘Blue’)
available from your Aquamax supplier. Anode replacement must be carried
out by an Aquamax accredited service agent.
Warning: If the water supply has a TDS greater than 600 mg/Litre and
the anode has not been changed to a blue anode, there is 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.
If the water heater has not been used for two or more weeks, follow the
procedure detailed in the “Anode” section on page 10 for safe dissipation of
the hydrogen gas build up inside the storage cylinder.
It must be noted that in areas where the TDS exceeds 600 mg/Litre, the
Aquamax warranty will not cover resultant faults on components including
the storage cylinder that fail due to the bad water conditions even though
an aluminium anode is fitted. Refer to “Water Chemistry Levels Affecting
Warranty” below for water chemistry levels and components affected.
The life of the water heater may also be extended by periodic inspection of
the anode and replacement if necessary (refer to “Periodic Maintenance”
on page 8 and “Anode” on page 10).

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Water Chemistry Levels Affecting Warranty
The Aquamax warranty of this water heater will not cover resultant faults on
components including the storage cylinder where water stored in the
storage cylinder exceeds at any time any of the following levels:
Total dissolved solids 600 mg/Litre
Total hardness 200 mg/Litre
Chloride 300 mg/Litre
Magnesium 10 mg/Litre
pH 9.5 and not less than 6.5
Calcium 20 mg/Litre
Sodium 150 mg/Litre
Iron 1 mg/Litre
Scaling Water
Scaling water is water that contains levels of calcium carbonate (total
hardness in excess of 200 mg/Litre at any time when the water heater is
operating). Scaling water can block and prevent the pressure &
temperature relief valve from operating resulting in damage to the water
heater storage cylinder and water heater components.
An ECV is mandatory in SA & WA and must be fitted in ALL areas with
scaling water to assist in preventing blockage of the pressure and
temperature relief valve.
Danger: Failure to install an expansion control valve where scaling
water conditions occur may result in the water heater storage cylinder
failing.
To avoid damage to the storage cylinder and water heater components,
Aquamax strongly recommend scaling water be treated before entering the
water heater by fitting appropriate water filters/conditioners etc. Refer to
your Local Water Authority for information on water in your area. A build up
of white sediment on hot water taps or shower roses can be indicative of
scaling water. Contact Aquamax if this condition is observed.
Note: Damage caused by scaling water can affect the Aquamax warranty.
(Refer to “Water Chemistry Levels Affecting Warranty” on page 13).
Spring, Dam, Bore & River Water Supplies
The Aquamax warranty of this water heater will not cover resultant faults on
components including the storage cylinder due to the effects of sludge
and/or sediment as a result of connection to a water supply from silted or
treated sources i.e. springs, dams, bores, rivers or towns supplied from a
bore.

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Troubleshooting
Check the items below before making a service call. If the water heater is
within/out of the warranty period you will be charged for attending to any
condition or fault that is not related to the manufacture or failure of a part.
For warranty terms and conditions (refer to “Warranty” on page 31).
Not Enough Hot Water (Or No Hot Water)
•Is the water heater’s electricity supply switched on?
Have your electrician check to ensure the water heater is switched on
and that there is electricity at the water heater.
Note: Check the electricity supply to which the water heater is
connected. If the water heater is connected to an Off-Peak or time
controlled electricity supply, heating hours will be restricted (refer to
“Off-Peak Electricity Supply” on page 4).
•Twin element water heaters
A twin element non simultaneous model must have power available to
the top heating unit circuit at all times for the water heater to operate as
designed. Have your electrician check to ensure this is the case.
•Are you using more hot water than you think?
Is one outlet (especially the shower) using more hot water than you
think? Very often the amount of hot water used is not realised,
particularly when showering. Carefully review the family’s hot water
usage. Have your plumber fit a flow control valve to each shower outlet
to reduce water usage.
•Pressure temperature relief valve running?
Is the PTR valve discharging too much water? (Refer to “Pressure
Temperature Relief Valve Running” below).
•Is the thermostat setting correct?
Ensure the thermostat setting is appropriate. Have your electrician
check and adjust the thermostat upwards to gain additional hot water
capacity. Refer to “Temperature Adjustment” on page 6.
Warning: Hotter water increases the risk of scald injury.
•For EM50 models; are the water heaters inlet and outlet connections
cross connected?
Refer to “Left and Right Hand Side Water Connections – EM50 Models”
on page 20 for acceptable cold water inlet and hot water outlet
connections. Cross connection of the water heaters inlet and outlet
connections on EM50 models will result in a reduction of the water
heater’s performance.

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Pressure Temperature Relief Valve Running
•Normal Operation
It is normal and desirable for the PTR valve to allow a small quantity of
water to escape during the heating cycle, however there may be a
problem if the valve continuously dribbles more than a bucket full of
water in a normal 24 hour cycle. Note: During the first 24 hours after
installation the valve may discharge more than a bucket full of water.
This is normal however excess discharge should only occur during the
initial 24 hour heat up period.
•Continuous dribble
Try gently raising the easing lever on the relief valve for a few seconds
(refer to “Pressure Temperature Relief Valve” on page 9). 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 use reconditioned relief valves and never replace
the relief valve with one of a higher pressure rating.
•Heavy flows of hot water until the water heater is cold - then stops until
water reheats.
The water heater must be switched off at the isolating switch or
switchboard. Phone Aquamax 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 supply line to the
water heater, it may discharge a small quantity of water instead of the
water heaters pressure temperature relief valve. This has the benefit of
conserving energy as the discharged water is cooler (refer to the “Cold
Water Supply Plumbing Arrangement” diagram on page 19 for expansion
control valve location).
Higher Than Expected Electricity Bills
Check the following points if your electricity bill is higher than expected:
•Is the relief valve running excessively?
Refer to “Pressure Temperature Relief Valve Running” on page 15.

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•Is one outlet (especially the shower) using more hot water than you
think?
Refer to “Not Enough Hot Water” on page 14.
•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 leaks.
•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 water heating tariff rate been increased by your electricity
retailer since your previous bill?
The electricity tariff to which your water heater is connected will
determine the overall operating cost of the system. It is important you
are aware of this tariff, i.e. Off-Peak (overnight) or time controlled
supply, Extended Off-Peak (overnight and day) or Extended time
controlled supply, Domestic/Continuous. Contact your energy supplier
for information relating to your water heating tariff rate.
If you have checked all the previous troubleshooting points and still
believe you need assistance, phone Aquamax Service or their nearest
Accredited Service Agent.
INSTALLATION
Installation Overview
This water heater must be installed by a qualified person in accordance
with the installation instructions. The installation must comply with the
requirements of AS/NZS 3500.4, AS/NZS 3000, all local codes and
regulatory authority requirements.
All packaging materials must be removed from the water heater prior to its
installation. This includes the removal of the cardboard base of the carton
from the underside of the water heater.
This water heater is not suitable for pool heating.
Hot Water Redundancy
If this water heater is to be used where an uninterrupted hot water supply is
necessary for the application or business, then there should be redundancy
within the hot water system design. This should ensure the continuity of hot

17
water supply in the event that this water heater was to become inoperable
for any reason. We recommend you provide advice to the system owner
about their needs and building backup redundancy into the hot water
supply system.
Water Heater Location
This water heater is suitable for either outdoor or indoor installation. The
water heater should be installed close to the most frequently used outlet
and its position chosen with safety and service in mind.
Sufficient and safe space for ease of service and access to heating unit,
thermostat, sacrificial anode and relief valve should be considered when
locating the water heater. The water heater must be installed upright in a
vertical position and must be accessible without the use of a ladder or
scaffold.
You must be able to read the information on the rating plate. If possible,
leave headroom of one water heater height so the anode can be inspected
and/or replaced. If adequate room is unavailable, the water heater must be
disconnected, drained and removed to enable servicing.
For outdoor installation, the water heater shall be installed freestanding on
a level and stable concrete base 50 mm thick.
For indoor installation or where property damage could occur, an overflow
tray and drain must be fitted in accordance with AS/NZS 3500.4. The drain
pipe from the tray should be periodically checked to ensure that it is not
blocked.
Do not install this water heater in a roof space as a mains pressure storage
water heater.
Note: Damage to the storage cylinder caused by incorrect installation is not
covered by warranty.

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Water Supplies
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
after the stop cock and before the non return valve as shown in the “Cold
Water Supply Plumbing Arrangement” diagram on page 19.
Model
EM50,
E80,
E125, E160
E
160X,
E250
E315, E400
Pressure temperature relief valve setting 1400 KPa 1000 kPa
Expansion control valve (ECV) setting * 1200 kPa 850 kPa
Max mains supply pressure With ECV 960 kPa 680 kPa
Without ECV 1120 kPa 800 kPa
* Expansion control valve not supplied with water heater.
Tank Water Supply
If the water heater is supplied with water from a tank supply and a pressure
pump system is not installed, then the bottom of the supply tank must be at
least 1 m above the highest point of the hot water plumbing system,
including the water heater. Care must be taken to avoid air locks. The cold
water supply line to the water heater must be adequately sized and fitted
with an approved full flow gate valve or ball valve and non return valve.
Water Supply Chemistry
Bad water can have a detrimental effect on water heater operation,
components and life expectancy and may affect warranty. Refer to “Water
Chemistry” on page 11 for more information. Also refer to “Spring, Dam,
Bore & River Water Supplies” on page 13.
Plumbing & Plumbing Diagrams
Plumbing Connections
All pipe work must be cleared of foreign matter before connection and
purged before attempting to operate the water heater. Use thread sealing
tape or an approved thread sealant on all fittings (never use hemp).
All Aquamax storage cylinder water
fittings have a plastic liner fitted. These
liners must be in place for the water
heater to function properly. All liners are
correctly positioned during manufacture
and should not require handling during
installation, however if a liner is not

19
correctly inserted or aligned, it should be
gently pushed back into place before
connecting any plumbing fittings.
Warning: Plastic liners must be in place for the water heater to function
properly. Do not remove or damage liners.
Warning: Do not use heat near plastic liners. Heat can be transferred
by conduction which may damage liners.
Water Inlet & Outlet Connections
An approved isolation valve and non return valve must be installed in the
supply line to the water heater.
A pressure limiting valve and expansion control valve may also be required
(for PLV requirements refer to “Water Supplies” on page 18 and for ECV
requirements refer to “Expansion Control Valve” on page 20).
A disconnection union must always be provided at the cold water inlet and
hot water outlet of the water heater to allow for water heater disconnection.
Left & Right Hand Side Water Connections – E80 ~ E400Models
All Aquamax mains pressure electric water heaters are manufactured with
dual inlets and outlets. For E80 ~ E400 models, the cold and hot water
supply can be connected to either side of the water heater. A kit containing
2 x ¾” brass plugs is supplied with the water heater to plug off the unused
cold and hot water supply fittings. When installing brass plugs, apply thread
sealing tape or an approved thread sealant to plug thread before
installation.