Vaillant ecoTEC pro User manual

Operating instructions
For the operator
GB, IE
Operating instructions
ecoTEC pro
Gas fired wall hung high efficiency boiler

Table of Contents
2Operating instructions ecoTEC pro 0020129673_00
Table of Contents
1 Notes on the documentation .....................................3
1.1 Storing documents ..........................................................3
1.2 Symbols used....................................................................3
1.3 Applicability of the instructions...................................3
1.4 Identification plate........................................................... 3
1.5 CE label...............................................................................3
2 Safety.................................................................................4
2.1 Safety and warning information ..................................4
2.1.1 Classification of warnings..............................................4
2.1.2 Structure of warnings.....................................................4
2.2 Intended use......................................................................4
2.3 Basic safety instructions................................................5
3 Equipment and functional description.................... 7
3.1 Design ................................................................................. 7
3.2 Function..............................................................................7
3.2.1 Heating mode....................................................................7
3.2.2 Domestic hot water generation....................................7
4 Operation ..........................................................................8
4.1 Overview of the control elements ...............................8
4.2 Digital Information and Analysis System (DIA) ........8
4.3 Operating concept ...........................................................9
4.4 Basic display.................................................................... 10
4.5 Operating levels ............................................................. 10
5 Operation ..........................................................................11
5.1 Putting the boiler into service......................................11
5.1.1 Opening/closing the isolator devices..........................11
5.1.2 Switching on the boiler...................................................11
5.1.3 Checking the filling pressure of the heating
system................................................................................12
5.1.4 Filling the heating system ...........................................12
5.2 Setting the heating flow temperature.......................13
5.2.1 Setting the heating flow temperature without a
controller connected......................................................13
5.2.2 Using a controller to set the heating flow
temperature .....................................................................13
5.3 Domestic hot water generation...................................13
5.3.1 Setting the hot water temperature ............................14
5.3.2 Activating/deactivating Comfort mode.....................14
5.4 Setting a room thermostat or weather
compensator ....................................................................14
5.5 Switching off Heating mode (summer mode) ..........15
5.6 Temporarily shutting down the boiler .......................15
5.7 Protecting the heating system against frost ...........15
5.7.1 Activating the frost protection function...................15
5.7.2 Draining the heating system........................................16
6 Energy saving tips........................................................17
7 Troubleshooting .............................................................19
7.1 Reading fault messages ................................................19
7.2 Detecting and rectifying malfunctions.................... 20
7.3 Rectifying a water shortage....................................... 20
7.4 Resolving ignition faults................................................21
7.5 Maintenance message ...................................................21
8 Live monitor (current status of the boiler).........22
9 Service.............................................................................23
9.1 Servicing the boiler.......................................................23
9.2 Caring for your boiler ...................................................23
10 Decommissioning .........................................................24
10.1 Disposing of the boiler .................................................24
10.2 Disposing of the packaging .........................................24
11 Manufacturer's guarantee and works customer
services. ..........................................................................25
11.1 Factory guarantee..........................................................25
11.2 Vaillant Service...............................................................25
12 Glossary ..........................................................................26
Index ............................................................................................27
Brief operating instructions .....................................................31

Notes on the documentation
Operating instructions ecoTEC pro 0020129673_00 3
1
1 Notes on the documentation
The following instructions are intended to guide you
throughout the entire documentation. Other documents
apply in addition to these operating instructions.
We accept no liability for any damage caused by failure to
observe these manuals.
Other applicable documents
When operating the ecoTEC pro, you must observe all oper-
ating instructions that are included with other components
of your system.
Further instructions for all accessories and controllers used
also apply.
The benchmark check list for starting up gas-fired boilers
(contained in the installation instructions) must be com-
pleted by the competent person present during the commis-
sioning and must be passed on to the system operator.
After reading through these instructions, if you have any
questions regarding the operation of the boiler, please con-
tact your recognised approved heating specialist company
or Vaillant‘s technical department.
In these instructions, the heating specialist company and
competent person approved by the Health and Safety Exec-
utive will be abbreviated as the heating specialist company
and skilled tradesman.
1.1 Storing documents
>Store these operating instructions and all other applica-
ble documents in such a way that they are available
whenever required.
>If you move out or sell the house, pass on the documents
to the relevant person as well.
1.2 Symbols used
The symbols used in the text are explained below: Symbols
for identifying dangers are also used in these operating
instructions (¬Section2.1.1).
iSymbol that denotes useful tips and infor-
mation
>Symbol for a required action
1.3 Applicability of the instructions
These operating instructions apply exclusively to appliances
with the following article numbers:
Boiler Type designation Article number
ecoTEC pro 24 (VUW GB 246/5-3) 0010011689
ecoTEC pro 28 (VUW GB 286/5-3) 0010011690
ecoTEC pro 28 (VUW GB 286/5-3) (LPG) 0010011718
1.1 Type overview
To find out the article number of your boiler, refer to the
identification plate.
1.4 Identification plate
The identification plate of your Vaillant ecoTEC pro boiler is
attached at the factory to the underside of your boiler.
The seventh to sixteenth digits of the serial number on the
identification plate represent the article number.
The serial numbers are also located on a plate, which is
stuck behind the front flap on the underside of the boiler in
a plastic fish plate (¬ Fig. 3.1 Item 2).
1.5 CE label
The CE label shows that the boilers comply
with the basic requirements of the applicable
directives as stated on the identification plate.
iVaillant Ltd. supports the Benchmark Initiative.
A benchmark checklist for commissioning gas-
fired boilers is attached to these installation
instructions. It is very important that this docu-
ment be filled out properly when installing, com-
missioning and handing-over to the operator of
the installation.

4Operating instructions ecoTEC pro 0020129673_00
a
Safety
a2
2 Safety
2.1 Safety and warning information
>When operating your boiler, take account of the general
safety instructions and the warning notes that appear
before each action.
2.1.1 Classification of warnings
The warning notes are classified in accordance with the
severity of the possible danger using the following warning
signs and signal words:
Warning signs Signal
word
Explanation
aDanger!
Immediate danger to life or
risk of
severe personal injury
eDanger!
Risk of death from electric
shock
aWarning!
Risk of minor personal
injury
bCaution!
Risk of material or environ-
mental damage
2.1 Meaning of warning signs and signal words
2.1.2 Structure of warnings
Warning signs are identified by an upper and lower separat-
ing line and are laid out according to the following basic
principle:
aSignal word!
Type and source of danger!
Explanation of the type and source of dan-
ger
>Measures for averting the danger
2.2 Intended use
The Vaillant ecoTEC pro boilers are state-of-the-art appli-
ances which have been constructed in accordance with rec-
ognised safety regulations. Nevertheless, there is still a risk
of injury or death to the operator or others or of damage to
the boiler and other property in the event of improper use
or use for which it is not intended.
This boiler is not intended for use by persons (including
children) having limited physical, sensory or mental capaci-
ties or who have inadequate experience and/or knowledge,
unless supervised by a person responsible for their safety
or who has been given instructions from them as to how to
operate the boiler.
Children must be supervised to ensure that they do not
play with the boiler.
The boiler is intended as a heater for closed hot water/cen-
tral heating installations and for hot water generation.
The use of the ecoTEC pro in vehicles, such as mobile
homes and caravans, is not classed as intended use. Units
that are not classed as vehicles are those that are installed
in a fixed and permanent location and that do not have any
wheels (fixed installation).
Any other use, or use beyond that specified, shall be con-
sidered as improper use. Any direct commercial or indus-
trial use is also deemed to be improper.
The manufacturer or supplier is not liable for any damage
resulting from such use. The user alone bears the risk.
Intended use includes the following:
– observing the included operating, installation and main-
tenance instructions for the Vaillant product and any
other parts and components of the system
– installing and fitting the appliance in accordance with the
boiler and system approval
– complying with all of the inspection and maintenance
conditions listed in the instructions.
Caution!
Any misuse is forbidden.

Operating instructions ecoTEC pro 0020129673_00 5
aSafety a
2
2.3 Basic safety instructions
>Observe the following safety instructions at all times.
Installation and adjustment
The boiler must only be installed by a suitably qualified
competent person. The existing regulations, rules and
guidelines must be observed when doing so.
He is also responsible for inspection, maintenance and
repairs to the boiler, and alterations to the gas volume set-
ting.
Procedure in case of gas smell in buildings
Installation errors, damage, handling, an unauthorised
installation site or similar can cause gas to escape and
result in a risk of poisoning and explosion. If there is a smell
of gas in the building, proceed as follows:
>Avoid rooms that smell of gas.
>If possible, open doors and windows fully and ensure
adequate ventilation.
>Avoid the use of naked flames (e.g. lighters, matches).
>Do not smoke.
>Do not use any electrical switches, mains plugs, door-
bells, telephones or other intercommunication systems in
the building.
>Close the gas meter isolator device or the main isolator
device.
>If possible, close the gas isolator cock on the boiler
(¬ Section 5.1.1).
>Warn other occupants in the building by calling out or
banging on doors or walls.
>Leave the building.
>If you can actually hear gas leaking, leave the building
immediately and ensure that others do not enter the
building.
>Alert the police and fire brigade once you are outside
the building.
>Use a telephone outside the building to inform the emer-
gency service department of the gas supply company.
National phone number for gas emergencies:
0800 111 999
What to do in an emergency if you smell flue gas
Installation errors, damage, handling, an unauthorised
installation site or similar can cause flue gas to escape and
result in a risk of poisoning. If there is a smell of flue gas in
the building, proceed as follows:
>Open all accessible doors and windows fully and ensure
adequate ventilation.
>Switch the boiler OFF.
>Inform a heating specialist company.
Explosives and highly flammable substances
The risk of explosion arises from the flammable mixture of
gas and air. Take note of the following:
>Do not use or store explosive or highly flammable sub-
stances (e.g. petrol, paper, paint) in the same room as the
boiler.
Preventing scalding
There is a danger of scalding at the hot water draw-off
points if the hot water temperatures are greater than 60 °C.
Young children and elderly persons are particularly at risk,
even at lower temperatures.
>Select the temperature so that nobody is at risk.
Preventing material damage due to unauthorised
changes to the appliance.
Take note of the following:
>Never interfere or tamper with the boiler or other parts
of the heating installation.
>Never try to carry out maintenance work or repairs on
the boiler yourself.
>Do not damage or remove any seals on components.
Only recognised heating specialist companies are author-
ised to alter sealed components.
Material damage caused by corrosion
To prevent corrosion on the boiler and also on the flue sys-
tem, note the following:
>Do not use sprays, solvents, chlorinated cleaning agents,
paint, adhesives or similar substances in the vicinity of
the boiler.
Under adverse circumstances these substances can cause
corrosion, even in the flue system.
Preventing frost damage
If there is a power cut, or if the room temperature is set too
low in individual rooms, it cannot be ruled out that sections
of the heating installation might be damaged by frost.
>If you are going to be away during a cold period, make
sure the heating installation remains in operation and
that the rooms are sufficiently heated.
>Always observe the information on frost protection pro-
vided in ¬ Section 5.7.
Even if rooms, or the whole dwelling, are not in use for cer-
tain periods, the heating must remain in operation.
Caution!
Frost protection and monitoring devices are only active
while the boiler is connected up to the power supply. The
boiler must be connected to the power supply. The boiler
must be switched on. You can see from symbols in the dis-
play that the boiler is switched on.

6Operating instructions ecoTEC pro 0020129673_00
a
Safety
a2
Caution!
>Under no circumstances should you add frost protection
agents (or other additives, e.g. jointing compounds, cor-
rosion protection agents, etc.) to the heating water with-
out first consulting your qualified skilled tradesman. Oth-
erwise, this could result in damage to seals and dia-
phragms as well as noises during heating mode. Vaillant
assumes no liability for this or any consequential dam-
age.
Another way to protect the heating system and the boiler
from frost is to drain them. In doing so, you must ensure
that the heating system and boiler are completely drained.
>Contact your approved heating specialist company for
advice on this.
Maintaining operation with an emergency power
generator in the event of a power cut
Your recognised heating specialist company connected your
boiler to the power mains during installation.
If the power supply is cut, it is possible that parts of the
heating installation may become damaged by frost.
If you want to maintain the operation of the boiler during a
power cut using an emergency power generator, take note
of the following:
>Make sure that the technical values of this generator
(frequency, voltage, earthing) match those of the power
mains.
>Contact your approved heating specialist company for
advice on this.
Changes to the surroundings of the boiler
You must not make any changes to the surroundings of the
boiler:
>Never shut down the safety devices.
>Do not tamper with any of the safety devices.
>Do not make any changes:
– to the boiler
– to the gas, air, water and electricity supply lines,
– to the entire flue system,
– to the entire condensate drain system,
– to the expansion relief valve or the drain line and
– constructional conditions that could affect the opera-
tional reliability of the boiler
Cupboard Installation
>If you require your boiler to be fitted into a kitchen type
cupboard then please consult your approved heating
specialist company. Under no circumstances must you
enclose your boiler yourself.
Enclosing the appliance in a cupboard requires compliance
with the special design instructions. This is to ensure all
necessary access is available for all necessary future
service requirements.
What to do if there are leaks in the hot water pipes
Take note of the following:
>In the event of leaks, immediately close the cold water
stop valve in the domestic hot water pipework between
the boiler and the draw-off points.
>Have the leak repaired by your approved heating special-
ist company.
With Vaillant ecoTEC pro boilers, the cold water stop valve
is not included in the scope of delivery of your boiler.
>Ask your approved heating specialist company where
they fitted the cold water stop valve.
Preventing damage caused by low system pressure
in the heating installation
To prevent the heating installation being used when the
amount of water is too low and to therefore prevent any
subsequent damage that may be caused by this, note the
following:
>Check the filling pressure of the heating installation at
regular intervals.
>Always observe the information on filling pressure pro-
vided in ¬ Section 5.1.3.
Requirements for the installation site
It is not necessary to keep a clearance between the boiler
and combustible materials or components since, at the
nominal heat output of your boiler, the temperature on the
surface of the casing is always lower than the maximum
permissible temperature of 85°C.

Equipment and functional description
Operating instructions ecoTEC pro 0020129673_00 7
3
3 Equipment and functional description
3.1 Design
1
2
3.1 Front view of the ecoTEC pro
Key
1 Controls
2 Plate with serial number on the rear
3.2 Function
Your Vaillant ecoTEC pro is a gas-fired wall-hung high-effi-
ciency boiler, which generates heat for heating and/or
domestic hot water generation.
3.2.1 Heating mode
In heating mode, the boiler heats the hot water and sends it
through the radiators or underfloor heating of your home
(heating circuit). The hot water pumped into the heating cir-
cuit exits the boiler at a specific heating flow temperature,
emits its heat into the rooms and flows back into the boiler
once cooled to return temperature. The heating water is
then heated again.
3.2.2 Domestic hot water generation
When you open a hot water valve (sink, shower, bath, etc.),
the boiler operates automatically and supplies hot water at
a temperature set by you.
When you close the hot water tap. the boiler automatically
stops producing hot water.
If you have activated Comfort mode, the boiler supplies you
with hot water at the requested temperature without you
having to wait for the water to heat up.
iTo prevent unnecessary energy loss, do not set
the temperature higher than is required.

Operation
8Operating instructions ecoTEC pro 0020129673_00
4
4 Operation
4.1 Overview of the control elements
50
1234
5
4.1 ecoTEC pro operator control elements
1On/off button for switching the boiler on or off
2Controller (accessory)
The Digital Information and Analysis System consists
of:
3Reset button to clear certain faults
4Operating buttons
5Display
4.2 Digital Information and Analysis System
(DIA)
The ecoTEC pro boiler is equipped with a digital information
and analysis system (DIA system). It consists of a display
showing symbols and 5 operation buttons. This system pro-
vides information on the operating status of your boiler and
helps you deal with problems.
The display lights up,
– if you switch the boiler on or
– if you press a button for the DIA system when it is
switched on. At first, pressing this button does not trig-
ger any other function.
The light automatically switches off after one minute if you
do not press any button.
50
1
2
3
4
8
7
6
5
4.2 DIA system with possible symbol displays
1Display of the present heating flow temperature, the
filling pressure of the heating system, the operating
mode or a fault code
2Display of the current configuration of the right-hand
selection button (after switching on the boiler and in
the basic display: = heating)
3Left and right-hand selection buttons
4Minus and plus button
5Chimney sweep mode (for chimney sweeps only)
6Access to status of the boiler (Live monitor)
7Display of the current configuration of the left-hand
selection button (after switching on the boiler and in
the basic display: = hot water generation)
8Display of the symbols for the active operating status

Operation
Operating instructions ecoTEC pro 0020129673_00 9
4
Displayed symbols
Flame:
Permanently on: Correct burner operation; burner
on
Display of the current filling pressure of the heating
system (bar graph display).
The filling pressure must be in the mid range
between the two dotted lines.
Permanently on: The filling pressure is within the
permitted range.
Flashing: The filling pressure is outside of
the permitted range (¬ Sec-
tion 5.1.3).
Heating mode active
Permanently on: Heating mode heat requirement
Flashing: Burner on in heating mode
Hot water generation active
Permanently on: In draw-off mode before burner is
on
Flashing: Burner on in draw-off mode
Comfort mode active
Permanently on: Comfort mode is activated
Flashing: Comfort mode is active,
burner on
Maintenance required. In the "Live monitor", you
can read further information about the reason for
the service (¬ Section 8).
Additional symbols:
Summer mode active
Heating mode is switched off
Burner anti-cycling time is active
This function is used to prevent frequent on/off
operations, and therefore contributes to prolonging
the life of your boiler.
The symbol also appears if the boiler is in a waiting
period.
F.X X
Fault in the boiler. Appears instead of the basic dis-
play (¬ Section 4.4).
Example: F.10
4.3 Operating concept
You can operate the boiler using the selection buttons and
the plus/minus buttons.
Both selection buttons have a soft key function. This means
that their function may change.
45
4.3 Display after pressing the left-hand selection button
If, forexample, you press the left-hand selection button in
the basic display (¬ Section 4.4),the current function
switches from " " (domestic hot water temperature) to
"" (Back).
With the left-hand selection button :
– you can navigate directly to set the domestic hot water
temperature
– you can cancel the change to a set value or the activa-
tion of an operating mode
With the right-hand selection button :
– you can navigate directly to set the heating flow temper-
ature, to the precise value of the water pressure of the
heating system and to activate Comfort mode
– you can confirm a set value or the activation of an oper-
ating mode

Operation
10 Operating instructions ecoTEC pro 0020129673_00
4
With both selection buttons at the same time
+ :
– you can display the current status of the boiler
With the minus button or the plus button
:
– you can increase or decrease a selected set value
Adjustable values are always displayed as flashing.
You must always confirm a change to a value. Only then is
the new setting saved.
You always have the option to cancel the change to a set-
ting or the reading of a value by pressing the left-hand
selection button.
iIf you do not press any buttons for more than 15
minutes, the display returns to the basic display.
Changes that are not confirmed will not be
applied.
4.4 Basic display
50
4.4 Basic display
In the normal operating status, you can see the basic dis-
play in the display. The basic display shows the current sta-
tus of the boiler. If you press a selection button, the rele-
vant activated function is displayed in the display. If the dis-
play becomes dark, the light is first switched on by the first
press of the button. In this case, to trigger the button func-
tion, you must press the button again.
You can switch back to the basic display by:
– pressing the left-hand selection button and exiting the
selection levels
– not pressing any button for longer than 15 minutes.
Changes that are not confirmed will not be applied.
If there is a fault, a fault message will be shown instead of
the basic display.
From the basic display, you can directly change and read
the most important settings and information by pressing
the selection buttons.
The functions that are available depend on whether a con-
troller is connected to the boiler.
4.5 Operating levels
The boiler has two operating levels.
Operating levels for the operator
The operating level for the operator offers you the most
frequently used setting options that do not require any spe-
cial prior knowledge and displays the most important infor-
mation.
Operating level for the heating engineer
The operating level for the heating engineer must only be
operated with expertise and is therefore protected by a
code. This level is used by the skilled tradesman to adjust
the parameters for the boiler to the heating system.

Operation
Operating instructions ecoTEC pro 0020129673_00 11
5
5 Operation
5.1 Putting the boiler into service.
5.1.1 Opening/closing the isolator devices
iIf the boiler is fitted with a bottom cover, the iso-
lating devices are under this cover.
90°
43
1
2
5.1 Opening the shut-off valves
The isolator devices are open if the slot for the screwdriver
is parallel to the pipes.
>Open the gas isolator cock (3).
>Check that the heating flow (4) and heating return (1)
isolator devices are open. Open these if they are closed.
>Open the cold water stop valve (2).
>In order to check this, open a hot water tap at a draw-off
point and check that water flows out.
Closing isolator devices
The isolator devices are closed if the slot for the screw-
driver is at a right-angle to the pipes.
5.1.2 Switching on the boiler
bCaution!
Risk of damage caused by frost.
Frost protection and monitoring devices are
only active while the boiler is connected up
to the power supply and your boiler is
switched on using the on/off switch.
>Do not isolate the boiler from the power
mains.
>Leave your boiler switched on at the on/
off switch.
To ensure that the frost protection and monitoring devices
remain active, switch your boiler on and off using the con-
troller (see the corresponding operating instructions for
more information on this).
¬Section10 describes how to fully shut down your boiler.
50
1
2
5.2 Switching on the boiler
>Press the on/off switch (1) to switch on the boiler.
If the boiler is switched on, the current heating flow tem-
perature and other information will appear in the display
(2) (¬ Fig.4.4 ).
To set your boiler to suit your needs, read Section 5.2 and
Section 5.3 which describe the setting options for domes-
tic hot water generation and the heating mode.

Operation
12 Operating instructions ecoTEC pro 0020129673_00
5
5.1.3 Checking the filling pressure of the heating
system
bCaution!
Low filling pressure can cause damage to
the unit.
Operating the heating installation with low
filling pressure can cause damage to the
boiler and the heating installation. The
boiler switches off automatically when the
filling pressure falls too low.
>Fill up the heating system as soon as the
filling pressure falls below 0.08MPa
(0.8 bar).
To avoid operating the system with insufficient water vol-
ume and to prevent possible damage associated with this,
your boiler is fitted with a pressure sensor and a digital
pressure display.
To ensure that the heating system operates smoothly, the
filling pressure when the heating system is cold must be
between 0.1 MPa and 0.2 MPa (1.0 bar and 2.0 bar) or lie
between the two dotted lines in the bar graph display.
If the heating system extends over several storeys, a higher
filling pressure may be required for the heating system.
>Ask your approved skilled tradesman for details about
this.
If the pressure falls below 0.08 MPa (0.8 bar), the right-
hand bar graph display and the current pressure flash in
the display.
>Fill up the heating system (¬ Section 5.1.4).
iSwitch off the boiler if the filling pressure in the
heating system falls below 0.05MPa (0.5 bar).
The display alternates between the fault mes-
sage F.22 and the current filling pressure.
The heating installation must be topped up with water
before the boiler can be put into operation again. As soon
as the system has been topped up with sufficient water, the
message disappears automatically after approx. 20 sec-
onds. If the pressure drops frequently the reason for the
loss of hot water must be identified and eliminated
>Contact your heating engineer.
You can see the filling pressure in the right-hand bar graph
display or display the exact value using the selection but-
tons to the right of the display.
0,8 3,0
1,0 1
2
3
5.3 Digital display of filling pressure
>Press the right-hand selection button twice.
The current filling pressure (1) and the minimum (3) or
maximum water pressure (2) that is to be set appear in the
display.
5.1.4 Filling the heating system
bCaution!
Risk of damage caused by tap water that
is extremely calciferous or corrosive or
contaminated by chemicals.
Unsuitable tap water damages the seals
and diaphragms, blocks components in the
boiler and heating installation through
which the water flows and causes noise.
>Only fill the heating installation with suit-
able tap water.
>In case of doubt, consult your approved
skilled tradesman regarding this.
To fill up and to refill the heating installation, you can nor-
mally use tap water. In exceptional cases, however, the
water quality may not be suitable for filling the heating
installation because the water is highly corrosive or calcif-
erous.
>If this is the case, contact your approved heating engi-
neer.
The heating installation is filled via a filling cock provided
by the installer.
>Ask your approved skilled tradesman where the filling
cock is located.
>Ask your approved skilled tradesman to explain how to
fill the heating system.
You can show the exact filling pressure in the display
(¬Section 5.1.3).

Operation
Operating instructions ecoTEC pro 0020129673_00 13
5
Proceed as follows to fill the heating installation:
>Open all radiator valves (thermostatic radiator valves) of
the heating installation.
>Connect the filling cock for the heating system, as
explained by your approved skilled tradesman, to a cold
water draw-off valve.
>Open the filling cock slowly.
>Fill it with water using the draw-off valve until the
required filling pressure is reached in the display.
>Close the draw-off valve.
>Bleed all the radiators.
>Then check the filling pressure on the display.
>Fill with more water if required.
>Close the filling cock.
>Remove the connection between the filling cock and the
draw-off valve.
>Return to the basic display.
5.2 Setting the heating flow temperature
5.2.1 Setting the heating flow temperature
without a controller connected
60
5.4 Setting the heating flow temperature
If no external controller is connected to the boiler, set the
heating flow temperature according to the respective out-
side temperature as follows:
>Press the right-hand selection button (" ").
The value of the heating flow temperature appears in the
display.
>Use the minus button or the plus button
to change the heating flow temperature.
>Confirm the change by pressing the right-hand selection
button (“ ”).
The heating flow temperature is factory-set for tempera-
tures up to 75°C.
If higher (or lower) values can be set on your boiler, this
means that your approved skilled tradesman has calibrated
your unit to adjust the maximum temperature to your heat-
ing system.
5.2.2 Using a controller to set the heating flow
temperature
If your boiler has a weather compensator or a room ther-
mostat control system, you must make the following set-
tings:
>Set the maximum heating flow temperature on the boiler
(¬ Section 5.2.1).
The actual heating flow temperature is automatically
adjusted by the controller (for information about this, see
the controller operating instructions).
5.3 Domestic hot water generation
aDanger!
Risk of being scalded by hot water.
There is a danger of scalding at the hot
water draw-off points if the hot water tem-
peratures are greater than 60°C. Young
children and the elderly can even be at dan-
ger at lower temperatures.
>Select the temperature so that nobody is
at risk.
aDanger!
Possible danger to life from legionella!
If the boiler is used to reheat water in a
solar-based drinking water heating system,
note the following:
>Set the minimum hot water temperature
to 60°C.
bCaution!
Risk of damage caused by calcification.
If the water hardness is more than
3.57
mol/m3(=357 mg/l), there is a risk of
calcification.
>Set the domestic hot water temperature
to a maximum of 50°C.

Operation
14 Operating instructions ecoTEC pro 0020129673_00
5
5.3.1 Setting the hot water temperature
45
5.5 Setting the hot water temperature
>Press the left-hand selection button (" ").
The domestic DHW temperature that is set is shown flash-
ing on the display.
>Use the minus button or the plus button
to change the domestic hot water tempera-
ture.
>Confirm the change by pressing the right-hand selection
button (“ ”).
If you have connected an eBUS auto controller to the boiler,
you can set the DHW target temperature on the controller.
>Ask your approved skilled tradesman whether an eBUS
auto controller is connected.
If you are using an eBUS auto controller:
>Set the hot water temperature on the boiler to the maxi-
mum possible temperature.
>Set the desired hot water temperature (hot water target
temperature) on your controller.
5.3.2 Activating/deactivating Comfort mode
Comfort mode immediately supplies you with hot water at
the required temperature, without you having to wait for
the water to heat up. To do this, the plate-type heat
exchanger of the ecoTEC pro is kept at your selected tem-
perature level.
Comf.
on
5.6 Switching Comfort mode on and off
>Press the left-hand selection button (" ").
>Press the right-hand selection button
(" ").
"Comf.on" or "Comf.off" are shown flashing in the display.
>Use the minus button or the plus button
to activate or deactivate Comfort mode.
>Confirm the change by pressing the right-hand selection
button (“ ”).
When you have activated Comfort mode, the symbol " " is
shown in the basic display.
When you have deactivated Comfort mode, the symbol " "
goes out in the basic display.
5.4 Setting a room thermostat or weather
compensator
2
1
5.7 Setting the room temperature controller/weather controlled
regulator
>Set the room thermostat, weather compensator (1) and
thermostatic radiator valves (2) as specified in the oper-
ating instructions for these accessories.

Operation
Operating instructions ecoTEC pro 0020129673_00 15
5
5.5 Switching off Heating mode (summer mode)
off
5.8 Switching off Heating mode (summer mode)
You can switch off the heating mode in summer without
switching off the domestic hot water supply.
>Press the right-hand selection button (" ").
The value of the heating flow temperature appears in the
display.
>Use the minus button to set the domestic hot
water flow temperature to "Off".
>Confirm the change by pressing the right-hand selection
button (“ ”).
Heating mode is switched off. The symbol appears on the
display.
To switch Heating mode on again:
>Use the plus button to set your required
heating flow temperature.
>Confirm the change by pressing the right-hand selection
button (“ ”).
5.6 Temporarily shutting down the boiler
bCaution!
Risk of damage caused by frost.
Anti-freeze and monitoring devices are only
active while the boiler is connected up to
the power mains and the on/off switch is
on.
>Do not isolate the boiler from the power
mains.
>Leave your boiler switched on at the on/
off switch.
>Only switch the boiler on and off in nor-
mal mode using the controller.
>Make sure that the boiler cannot become
damaged by frost.
50
1
2
5.9 Switching off the boiler
>Press the on/off switch (1) to switch the boiler off.
If the boiler is switched off, the display (2) turns off.
iIf the boiler is going to be unused for longer
periods (e.g. holiday), you should also close the
gas isolator cock and the cold water stop valve,
but only if there is no risk of frost.
5.7 Protecting the heating system against frost
5.7.1 Activating the frost protection function
Your Vaillant ecoTEC is fitted with a frost protection func-
tion for each boiler:
If the heating flow temperature falls below 5°C when the
on/off switch is on, the boiler comes into operation and
heats the heat generation circuit to approx. 30°C on both
the heating side and the domestic hot water side (if availa-
ble).
bCaution!
Risk of damage caused by frost.
The frost protection function cannot guar-
antee flow through the entire heating
installation, which means that parts of the
heating installation may freeze and become
damaged.
>Make sure that the boiler remains on
whilst you are away.
>Make sure that the rooms are heated suf-
ficiently.

Operation
16 Operating instructions ecoTEC pro 0020129673_00
5
5.7.2 Draining the heating system
Another way to protect the heating system and the boiler
from frost when they are switched off for a very long time
is to drain them. You must ensure that the heating installa-
tion and boiler are completely drained.
All the cold and hot water pipes in the house and in the
boiler must also be drained.
>Ask your heating engineer to drain the heating installa-
tion.

Energy saving tips
Operating instructions ecoTEC pro 0020129673_00 17
6
6 Energy saving tips
Fitting a weather compensator
Weather compensators regulate the heating flow tempera-
ture according to the outside temperature. Thus it is
ensured that heat in excess of what is required at that
moment is not generated. In addition, desired heating and
set-back phases (e.g. at night) are automatically turned on
and off by using integrated time programmes.
Weather compensators combined with thermostatic radia-
tor valves are the most economical form of heating regula-
tion.
Operating the heating system in energy-saving
mode
>Reduce the room temperature for the night and for peri-
ods when you will be absent.
The simplest and most reliable way is to be able to reduce
the room temperature using the controller with individually
selectable timer programmes.
>At such times, set the room temperature approx. 5°C
lower than during full heating times.
If you reduce the room temperature by more than 5°C, you
do not save any additional energy, because increased heat-
ing capacities would then be required for the next full heat-
ing period. Only for longer absences, e.g. during holidays, is
it worthwhile to lower the temperatures further.
Caution!
>In winter, make sure that adequate frost protection is
maintained (¬ Section 5.7).
Room temperature
>Set the room temperature only as high as would be
enough for your comfort level.
Each extra degree would cause an increased energy con-
sumption of about 6%.
>Adjust the room temperature according to the purpose
of use of the room.
For example, normally, bedrooms or rooms that are seldom
used are heated to 20°C.
Uniform heating
>Heat all rooms in your dwelling evenly and according to
their use.
If you are only heating one room or individual rooms in
your dwelling, the unheated adjoining rooms are also
heated in an unregulated manner through walls, doors, win-
dows, roofs and floors. The capacity of the radiators in the
heated rooms is obviously not enough for such an operat-
ing mode. It is then not possible to heat up the heated
rooms sufficiently (the same effect arises when doors
between heated and unheated/partially heated rooms are
left open).
Thermostatic radiator valves and weather compen-
sators or room thermostats
Thermostatic valves on all radiators maintain the room tem-
perature exactly once they have been set. You can adjust
the room temperature to suit your individual requirements
and ensure effective operation of your heating system
using thermostatic valves in combination with a room ther-
mostat or a weather compensator.
How the thermostatic radiator valve works: If the room
temperature rises above the value set on the sensor head,
the thermostatic radiator valve shuts off automatically, and
when the temperature drops below the defined value, it
opens again.
Do not obstruct the controller
>Do not obstruct your controller with furniture, curtains
or other objects.
The controller must be able to record the circulating room
air unhindered. Covered thermostatic radiator valves can be
equipped with remote sensors and thus still work.
Ventilating living rooms
>During the heating period, open windows only for venti-
lation and not to regulate the temperature.
Brief ventilation is more effective and energy-saving than
leaving windows open for a long time.
Close all the thermostatic valves in the room during ventila-
tion.
>If you have a room thermostat installed, set it to mini-
mum temperature.
This guarantees adequate exchange of air without unneces-
sary loss of energy and cooling off.
Setting the operating mode
>In warmer seasons, when the dwelling needs no heating,
turn the heating to summer mode.
Heating mode is then switched off. The boiler and system
remain ready for operation for the domestic hot water gen-
eration.
Setting the hot water temperature
>Only heat the warm water up to the extent that is neces-
sary for use.
Any further heating results in unnecessary power consump-
tion and domestic hot water temperatures of more than
60°C also lead to increased limescale sediment.
Switching on Comfort mode
Comfort mode immediately supplies you with hot water at
the required temperature, without you having to wait for
the water to heat up. For this, the hot water heat exchanger
is kept at a preselected temperature level.
If you do not need hot water for a long period, it is recom-
mended to turn off comfort mode to save energy further.

Energy saving tips
18 Operating instructions ecoTEC pro 0020129673_00
6
Energy-conscious use of water
Responsible use of water can reduce your bills considerably.
For example, taking a shower instead of a bath: While about
150 litres of water are required for a bath, a modern shower
equipped with water-saving fittings only requires a third of
this volume.
By the way: A dripping water tap wastes up to 2000 litres
of water and a leaking toilet flush wastes up to 4000 litres
of water each year.

Troubleshooting
Operating instructions ecoTEC pro 0020129673_00 19
7
7 Troubleshooting
aDanger!
Risk of injury and material damage due
to incorrect maintenance and repairs.
If maintenance is not carried out, or carried
out incorrectly, this may adversely affect
the operational reliability of your boiler.
>Never perform maintenance work or
repairs on your boiler by yourself.
>You must employ an approved skilled
tradesman or
Vaillant Service Solutions
(0870 6060 777) to complete such work.
7.1 Reading fault messages
F.75
7.1 Fault display
Fault messages have priority over all other displays. If a
fault develops in the boiler, the display shows a fault code
instead of the basic display, e.g. F.75 (Fault Pump/water
shortage).
If multiple faults occur at the same time, the display shows
the corresponding fault codes for two seconds each in
sequence.
>If your boiler displays a fault message, contact your
approved skilled tradesman.
You can use the "Live monitor" function to call up status
messages about the status of your boiler (¬ Section).

Troubleshooting
20 Operating instructions ecoTEC pro 0020129673_00
7
7.2 Detecting and rectifying malfunctions
If problems occur whilst operating your boiler, you can
carry out the following self-checks:
Problem Possible cause Solution
No hot water,
heating stays cold;
boiler does not start
Building gas isolator cock closed >Open building gas isolator cock
(¬
Section 5.1.1)
Building power supply switched off >Switch on building power supply
On/off switch on boiler switched off >Switch on the on/off switch on the
boiler(¬ Section 5.1.2)
The heating flow temperature is set too low or in the
"Heating off" position (¬ Section 5.5) and/or the
domestic hot water temperature is too low
>Set the heating flow temperature to the
desired temperature (¬ Section 5.2) and/or
set the domestic hot water temperature to
the desired temperature (¬ Section 5.3.1).
Filling pressure of the heating installation too low >Top up the heating system with water
(¬ Section 5.1.4)
Air in the heating installation >Purge the radiators. >If the problem occurs again:
Inform the competent person
Ignition malfunction >Press the Fault clearance button >If the problem occurs again:
Inform the competent person (¬
Section7.4).
DHW mode without any prob-
lems;
Heating does not start No heating demand via the controller
>Check the timer programme on the control-
ler and correct it if necessary.
>Check the room temperature and, if
required, correct the target room tempera-
ture
(¬ Section5.4; Controller operating
instructions).
7.1 Detecting and rectifying malfunctions
>If, after checking the points mentioned in Table 7.1, your
boiler still shows signs of a fault, contact your approved
skilled tradesman to eliminate the problem.
7.3 Rectifying a water shortage
0,7bar
7.2 Display of the filling pressure for the heating system is too
low
If the filling pressure for the heating system falls below
0.08MPa (0.8 bar), the red bar display and the current fill-
ing pressure flash in the display.