Dux 25V1 User manual

H0420 Version C
OWNER’S MANUAL
WARRANTY INFORMATION AND
INSTALLATION INSTRUCTIONS
PROFLO™ AND MARATHON™
ELECTRIC STORAGE WATER HEATERS
MODELS:
25V1, 25P1, 50V1, 50P1, 50H1, 80F1, 80H1,
125F1, 125F2, 125H1, 160F1, 160F2, 160H1,
250F1, 250F2, 250T1, 250T2, 250H1, 250H2,
315F1, 315F2, 315T1, 315T2, 315H1, 315H2,
400F1, 400F2, 400T1, 400T2, 400H1, 400H2
FOR ADVICE, REPAIRS AND SERVICE:
1300 365 115 (AUSTRALIA)
0800 729 389 (NEW ZEALAND)
Effective for all Mains Pressure Storage Hot Water Units manufactured and sold after the 1st July 2005

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CONTENTS
APPLIANCE & SERVICE DETAILS 3
INSTALLATION DETAILS 4
OPERATING INSTRUCTIONS 6
SERVICE INFORMATION 8
WARRANTY 10
SPECIFICATIONS 13
WELCOME TO DUX HOT WATER
Your decision to purchase a Dux water heater will reward you for many years to come.
Since 1915, the Dux range has seen continuous research and development, resulting in
many breakthroughs in the efficiency, reliability and longevity of hot water systems.
Dux water heaters are manufactured in Australia in a state-of-the-art facility, using a
Quality Endorsed Company production system.
This is your assurance that you have purchased the highest quality water heater available,
one that will provide continuous hot water for all your needs - safely, economically, and for
many years to come.
FEATURES OF YOUR DUX®
ELECTRIC WATER HEATER
•Unique Positive Domed, butt welded tank provides superior corrosion resistance,
resulting in longer life.
•Advanced heating design for better reliability.
•High efficiency design.
•Adjustable Thermostat - allows you to adjust water temperature, saving energy costs
during warmer months of the year (single element models only).

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WARRANTY CARD
Enclosed you will find a warranty card - please fill in the details and return immediately.
This will ensure prompt service under warranty, if required.
Product Warranty only applicable in Australia and New Zealand.
See page 11 for terms of warranty.
Privacy Act Amendment 2000; If and whenever warranty service is required, your personal details will only
be given to an Authorised Dux Service Agent for the express purpose of carrying out the arranged warranty
service work agreed by you the client and Dux Manufacturing Limited.
APPLIANCE DETAILS
For future convenience, would you kindly fill in the following details and retain with your
original invoice for your own records.
OWNER’S DETAILS:
Surname:........................................... Given
Name(s):..................................................
Address:............................................................................................................................
Town/Suburb:....................................................................................................................
State/Territory:................................................... Postcode:....................
Date of Purchase:.......................... Purchased From:......................................................
Model:............................................ Serial Number:.........................................................
Date of Manufacture:....................................................................................................
(Details on Data Plate on water heater)
INSTALLER’S DETAILS:
Date of Installation:......................... Installer’s Name:....................................................
Address:............................................................................................................................
Installer’s Signature:.........................................................................................................
SERVICE DETAILS
Date of Service:......................... Serviced By:..........................................................
Work Carried Out:.......................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
Signature of Service Agent:........................................................................................

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INSTALLATION DETAILS
This water heater must be installed by a licenced tradesperson, and in accordance with
•AS/NZS3500.4.2 “National Plumbing and Drainage Code Hot Water Supply
Systems – Acceptable Solutions” .
•Local authority regulations.
•Outside Australia and New Zealand, please refer to local plumbing and building
codes and regulations.
•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.
Note: This water heater is not suitable for pool heating.
This water heater is designed for direct connection to water supply pressures of:
•25 to 160 Litre Models - 1100kPa
•250 to 400 Litre Models - 800kPa
Where the mains pressure can exceed or fluctuate beyond the pressure shown above, a
pressure limiting device (complying with AS1357) must be fitted in the cold water inlet
supply. This device must be installed after the isolating valve and set at or below the
pressure shown above. Note during periods of lower demand water pressure may
increase.
CAUTION: This water heater delivers hot water at temperatures exceeding 50oC. Refer
to AS/NZS3500 and local regulations regarding the need for additional hot water delivery
temperature control.
LOCATION
The water heater should be located as close as possible to the most frequently used hot
water outlet. Adequate access must be made for service to the element, thermostat, relief
valve and anode. Ensure that the data plate is clearly visible.
Note:All models are equipped with a sacrificial anode, accessible through the top cover.
Allow 50% of the height of the water heater for clearance above to replace the anode.
The water heater has a plastic base which is resistant to water damage but it is
recommended that a plinth be installed under the water heater when the water heater is
subjected to wet conditions. A properly drained overflow tray must be used where property
damage could occur from water spillage. (See AS/NZS3500.4.2 for further details.)
When installing this water heater in a roof area as a mains pressure unit refer to local
regulations.
Note: The warranty does not cover damage due to leakage of the water heater.

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Figure 1: Installation Diagram
PRESSURE & TEMPERATURE RELIEF VALVE
The Pressure & Temperature relief valve is supplied loose with the water heater. The
valve rating is:
•25 to 160L Models - 1400kPa
•250 to 400L Models - 1000kPa
The relief valve must be installed directly into the top socket marked “RELIEF VALVE”.
The drain line from this valve must be installed in a continuously downward direction in a
frost free ambient position with the discharge end left open to atmosphere permanently.
The Pressure & Temperature Relief Valve supplied with the water heater is not sufficient to
enable connection of the water heater to supplementary energy sources such as solar
panels or slow combustion stoves (refer AS/NZS 3500.4.2 for guidance on these types of
installations)
Note: Plugs are supplied with the water heater to plug off the fittings that are not required.
Ensure that a sealing material is applied to the plugs for a leak tight fit.
ANODE ACCESS THROUGH PLUG
DATA PLATE
HOT WATER
OUTLET
TEMPERATURE
AND PRESSURE
RELIEF VALVE
DRAIN
ELEMENT COVER
TEMPERATURE ADJUSTMENT PLUG
(USER ADJUSTABLE MODELS ONLY)
EXPANSION VALVE ONLY
REQ'D WHERE LOCAL
REGULATIONS DEMAND.
DRAIN
ISOLATING VALVE
(SPINDLE VERTICLE)
COLD WATER
INLET
LINE STRAINER
NON RETURN VALVE UNION CONNECTION
NOTE: A COMBINED ISOLATING VALVE/NON RETURN
VALVE/LINE STRAINER MAY BE USED
INSTALLATION DIAGRAM

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COLD WATER CONNECTION
An approved isolating valve, approved non return valve, line strainer (optional but
recommended), and union must be fitted between the supply main and the RP¾/20 socket
in the water heater. All fittings must be approved by the relevant Authority. See the
Installation Diagram for details.
Note for S.A. and W.A.: It is a state requirement that a pressure relief valve be fitted on
the cold water supply line between the non return valve and the water heater (refer to
Installation Diagram).
Warning: A separate drain line must be run for this relief valve. It is not permitted to
couple drain lines from relief valves into a single common drain line.
HOT WATER CONNECTION
The hot water pipe should be connected to the RP¾/20 socket as shown on the
Installation Diagram. For the most economical operation of the water heater, it is
recommended that all hot water lines are insulated. Please check local regulations
regarding the use of hot water supply pipework other than pipes made of copper.
ELECTRICAL CONNECTION
This water heater is designed for single phase 240V A.C supply only. The electrical
connection must comply with Local Supply Authority Regulations and AS3000.
For models not pre-wired with a flexible lead, connections are made at the terminal block
inside the water heater. Entry to the connection area is through the hole beneath the
element cover, designed to accept a 20mm conduit. The element cover may be removed
by undoing the two screws on the cover and sliding the cover downwards to disengage the
top edge. Ensure that the conduit entry is well sealed to achieve correct weatherproofing.
Note: This water heater is fitted with a thermostat and over-temperature energy cut-out. Under no
circumstances should the water heater be operated without both these devices being in the circuit.
Replacement must be carried out only by a qualified electrician or the manufacturer.
DANGER - The operation of the thermal cut-out indicates a possibly dangerous situation.
Do NOT reset the thermal cutout until the water heater has been serviced by a qualified
person.
Flexible Lead Models: If the power supply lead is damaged, it should be replaced by a
lead assembly available only from Dux Manufacturing service agents.
Caution: The water heater must be filled with water before turning on the electricity
supply.
Electrician: Press reset button on thermostat(s) to ensure over-temperature cut-out is set.
OPERATING INSTRUCTIONS
The appliance is not intended for use by young children or infirm persons without
supervision. Young children should be supervised to ensure that they do not play
with the appliance.
THERMOSTAT
On models equipped with a user adjustable thermostat the temperature may be adjusted
as follows:
(i) Remove the black plastic plug from the element cover.
(ii) Adjust the temperature using a screwdriver.
(iii) Ensure that the plastic plug is replaced.

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FILLING THE WATER HEATER
Open all hot water taps. Open isolating valve at the cold water inlet and allow water
heater to fill until water flows through the system. Close each hot water tap after the air is
expelled from its line. As noted previously power is not to be turned on until the water
heater is filled with water.
WATER QUALITY
Your Dux water heater has been manufactured to suit water conditions of most Australian
metropolitan supplies. Please note that harsh water supplies can have a detrimental
effect on the water heater and its life expectancy. If you are unsure about your water
quality you can obtain information from your local water supply authority.
The water heater is designed for use in areas where the Total Dissolved Solids (TDS)
content of the water supply is less than 2500 mg/L. In areas where the TDS exceeds
600mg/L it is possible that the magnesium alloy anode (supplied in the heater) may
become over reactive. To alleviate this, the magnesium alloy anode should be replaced
with an aluminium alloy anode, available from your local Dux supplier.
•Hard Water Models : Water heaters with an “H” in their model designation (eg.
250H136) are factory fitted with an aluminium anode and a special hard water
element.
Water can also be very corrosive, the measure of this is the saturation index, if the water
saturation index is greater than 0.40 a expansion control valve should be fitted and where
the index is greater than 0.80 the water heater installed should be a Hard Water Model.
Please consult our Service Department for advise if required.
CAUTION!
If the water heater is left in an operating condition and unused for two weeks or more, a
quantity of hydrogen (which is highly flammable) may accumulate in the top of the water
cylinder. To dissipate this gas safely it is recommended that a hot tap be turned on for
several minutes at a sink, basin or bath, but not a dishwasher, clothes washer or other
appliance. During this procedure there must be no smoking, open flame or any other
electrical appliance operating nearby. If hydrogen is discharged through the tap it will
probably make an unusual sound as with air escaping.
Where the Water Heater is not installed in accordance with the listed advice the
water heater will not be covered by the Terms of Warranty.
SAFETY INFORMATION
WARNING:
For safe performance this water heater is fitted with:
1. Thermostat.
2. Over-temperature energy cut-out.
3. 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 is fitted and in
working order.
The element cover(s) should be removed only by an electrician.

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The electrical power supply switch must be turned off and the fuse removed at the main
electrical supply switchboard before the water heater electrical cover is removed.
The Pressure & Temperature relief valves should be checked for adequate performance or
replaced at intervals not exceeding 5 years, or less in areas where local regulations apply.
The lever on the relief valve must be pulled to operate the valve at least once every 6
months.
DANGER
Failure to operate the relief valve easing gear at least once every six (6) months may
indicate a problem with the water heater.
IMPORTANT
The Pressure & Temperature relief valve and the drain outlet pipe must not be sealed or
blocked. It is normal for the valve to overflow during heating cycles.
SERVICE INFORMATION
SIX MONTHLY SERVICE
(BY OWNER)
Operate the Pressure & Temperature relief valve for approximately 10 seconds by
operating the easing lever on the valve to ensure water is relieved to waste through the
relief drain pipe. Check to ensure the valve closes correctly.
FIVE YEAR SERVICE
(BY AUTHORISED PERSONNEL ONLY)
The five yearly service should be carried out by a licenced tradesperson. It is
recommended that this service be carried out by your local Dux agent. The service should
include the following:
•Replace the Pressure & Temperature relief valve.
•Replace the anode. (in areas of harsh or adverse water conditions it is recommended
that you carry out a more frequent check of your anodes condition, refer Operating
Instructions “Water Quality”)
•Flush the water heater.
To drain and flush the water heater:
(i) Turn off the power.
(ii) Turn off the cold water supply to the water heater at the isolating valve.
(iii) Gently operate the easing lever on the Pressure & Temperature relief valve to
release the pressure in the water heater.
(iv) Disconnect the cold water inlet union to the heater and attach a drain hose.
(v) Gently operate the Pressure & Temperature relief valve to let air into the heater and
allow water to escape through the hose.
(vi) To flush the heater, carry out steps (i) to (iv) above. Disconnect the hot water inlet
union and attach a water supply hose to the heater. Turn on the water supply.
(vii) Flush the heater until clear water appears. Reconnect all fittings, fill the heater and
restore the electricity supply.

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RECOGNITION OF ABNORMAL OPERATION
1. PRESSURE & TEMPERATURE RELIEF VALVE RUNNING
It is not unusual for this to allow a small quantity of water to escape during the heating
cycle. The amount of discharge will depend on hot water usage. As a guide, if it
discharges more than 20 litres of water in 24 hours there may be a problem.
Continuous trickle:
Likely build up of foreign matter. Try gently raising the easing lever on the Pressure &
Temperature relief valve for a few seconds. This may dislodge a small particle of
foreign matter and rectify the fault. Release lever gently.
Steady flow:
Likely causes are excessive water supply pressure, a faulty Pressure & Temperature
relief valve or a faulty thermostat. Turn off the electricity supply and contact your Dux
agent.
2. NO HOT WATER
Is the Pressure & Temperature relief valve discharging too much water? See “Pressure
& Temperature Relief Valve Running”.
Do you have the correct size water heater for your requirements? Sizing details are
available from your Dux supplier.
Is one outlet (such as the shower) using more hot water than you think?
Carefully review the family's hot water usage and if necessary check the shower flow
rates with a bucket and a watch. If it is not possible to adjust water usage patterns, an
inexpensive flow control valve can easily be fitted to the shower outlet.
3. HIGH ELECTRICITY BILLS
Is the Pressure & Temperature relief valve discharging too much water? See “Pressure
& Temperature Relief Valve Running”.
Is one outlet (such as the shower) using more hot water than you think? See “No Hot
Water”.
Is there a leaking hot water pipe or dripping hot water tap? A small leak can waste a
large quantity of hot water.
Replace faulty tap washers and have your plumber rectify any leaking pipework.

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Dux Hot Water Unit
Manufactured by Dux Manufacturing Limited (“Dux”)
Terms of Warranty and Replacement Guarantee
Effective for all Mains Pressure Storage Hot Water Heaters manufactured and sold after 1st July
2002.
THE DUX HOT WATER UNIT THAT YOU HAVE PURCHASED COMES WITH A
COMPREHENSIVE 1 YEAR PARTS AND LABOUR WARRANTY AND A GUARANTEE TO
REPLACE YOUR HOT WATER UNIT IF THE INNER CYLINDER FAILS WITHIN 5 TO 10 YEARS,
DEPENDING ON THE MODEL YOU HAVE PURCHASED. The terms of the Warranty and
replacement guarantee are set out below.
WARRANTY
1. Your hot water unit and its components are covered by a 1 year warranty against defective
factory parts or workmanship from the date your hot water unit is installed. If the date of
installation is unknown, the warranty commences 1 month after the date of manufacture (which
can be found on the serial plate on the hot water unit).
2. This warranty is for normal use of the hot water unit and covers the repair and/or replacement
of any failed component in the hot water unit or where necessary , the hot water unit itself.
Under this warranty Dux will repair or replace the component or hot water unit free of charge
(except for certain transport or travelling time costs which may be payable by the owner under
clause 9 below). The decision to repair or replace the component or hot water unit will be
entirely at the discretion of Dux.
3. The warranty only applies to defects in the hot water unit which have arisen solely due to faulty
materials or workmanship.
5 Year Replacement Guarantee.
4. If an inner cylinder fails on a Dux hot water unit (other than a Dux “Marathon” model), within a
further 4 years after the end of the 1 year warranty period, Dux will provide a free replacement
hot water unit at the nearest approved Dux agent or Dux office to the owners home. Under this
replacement guarantee, the transport, installation and labour costs of delivering the
replacement hot water unit and removing and replacing the existing hot water unit with the
replacement hot water unit will be charged to the responsibility of the owner of the existing hot
water unit.
10 Year Replacement Guarantee.
5. If the inner cylinder fails on a Dux “Marathon” hot water unit model No 250T1, 250T2, 315T1,
315T2, 400T1,or 400T2 within a further 9 years after the end of the 1 year warranty period,
Dux will provide a free replacement hot water unit at the nearest approved Dux agent or Dux
office to the owners home. Under this replacement guarantee, the transport, installation and
labour costs of delivering the replacement hot water unit and removing and replacing the
existing hot water unit with the replacement hot water unit will be charged to the responsibility
of the owner of the existing hot water unit.

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Scope of Warranty and Guarantee
6. The warranty and replacement guarantee do not apply to any defects or damage not due to
faulty factory parts or workmanship, including but not limited to defects or damage caused by
or resulting from:-
a) accidental damage, abuse, misuse, maltreatment, abnormal stress or strain, harsh or adverse
water conditions, contamination or corrosion from particles in the water supply, excessive
water pressure or temperature or neglect of any kind to the hot water unit or its components.
b) alteration or repair of the hot water unit other than by an approved Dux agent or a Technician
of a gas or electricity utility approved by Dux.
c) attachment of any parts or accessories other than those manufactured or approved by Dux;
and
d) faulty or improper installation of the hot water unit, including installation otherwise than in
accordance with the instructions contained in the owner’s manual supplied by Dux.
7. The warranty only applies to the hot water unit and/or components in the hot water unit and
does not cover any plumbing or associated parts, including but not limited to, pressure limiting
valves, stop cocks, non return valves, electrical switches, pumps or fuses, supplied by any
person installing the hot water unit.
8. Where a hot water unit or a component in a hot water unit is replaced by Dux, the balance of
any original warranty or replacement guarantee period will remain effective. The replacement
part or hot water unit does not carry any additional warranty or replacement guarantee.
9. Where the hot water is located outside the metropolitan area of a capital city and is:-
a) more than 25 kilometres from a Dux office; or
b) more than 25 kilometres from a Dux agent
the owner will be responsible under the warranty, for paying the costs of transporting the hot water
unit or any component in the hot water unit to and from an approved Dux agent or to a Dux office
(including the costs of any insurance associated with that transport) or paying the travelling time of
an approved Dux agent to and from the owner’s house premises.
10. Where the warranty applies but the hot water unit is installed or located in a position that does
not comply with the Dux installation instructions or any relevant statutory requirements, the
owner of the hot water unit will be responsible for the costs of:-
a) the dismantling or removal of cupboards, doors, walls of special equipment and
b) any labour required.
to gain access to and to bring the unit to a position that complies with the installation instructions
or relevant statutory requirements.
11. Dux’s obligations under this warranty and replacement guarantee are limited to repairing or
replacing the hot water unit or components. To the extent permitted by law, Dux will not be
liable for any loss or damage to furniture, carpets, walls, foundations or any other
consequential loss of any kind caused by a defect in the hot water unit or any component.
12. Any claim under the warranty or replacement guarantee must include full details of the defect
and/or damage to the hot water unit and/or component in the hot water unit. All claims must be
made within one month of the detection of the defect.

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13. In addition to this warranty and replacement guarantee, certain legislation (including the Trade
Practices Act 1974 and consumer protection legislation of the States and Territories) gives the
owner certain rights which cannot be excluded, restricted or modified. Nothing in this warranty
and replacement guarantee has the effect of excluding, restricting or modifying those rights.
14. In the case of a hot water unit acquired for other than personal domestic or household use,
Dux’s liability for a breach of a condition or warranty implied by Division 2 of Part V (other than
Section 69) of the Trade Practices Act (1974) and any equivalent State or Territory legislation
is expressly limited to any one or more of the following, as determined by Dux:-
a) the replacement of the hot water unit;
b) the repair of the hot water unit;
c) the payment of the cost of replacing the hot water unit or of acquiring an equivalent hot water
unit;
d) payment of the cost of having the hot water unit repaired.

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SPECIFICATIONS
Heater Dimensions (mm)
Size (L) A B C D E F
25 418 485 404 255 132 75
50 673 485 404 510 132 75
80 1007 524 459 836 170 80
125 1062 597 532 857 206 116
160 1317 597 532 1112 206 116
250 1444 682 617 1231 215 125
315 1754 682 617 1541 215 125
400 1703 770 705 1466 240 150
D
E
B
C
A
F