Vaillant ecoTEC plus VU Series User manual

en Operating instructions
ecoTEC plus
VU../VUW../VUI..
0020308119_02 - 28.11.2022

2Operating instructions 0020308119_02
Operating instructions
Contents
1 Safety ............................................ 3
1.1 Intended use .................................. 3
1.2 Qualification ................................... 3
1.3 General safety information............. 3
2 Notes on the documentation ...... 6
3 Product description..................... 6
3.1 Display and control elements......... 6
3.2 Displayed symbols......................... 7
3.3 Serial number ................................ 7
3.4 CE marking .................................... 7
3.5 UKCA mark.................................... 8
3.6 Hot Water Association ................... 8
3.7 Benchmark..................................... 8
4 Operation...................................... 8
4.1 Operating concept ......................... 8
4.2 Setting the language...................... 9
4.3 Activating/deactivating the
button lock ................................... 10
4.4 Heating mode .............................. 10
4.5 DHW mode .................................. 10
4.6 Using the sensoROOM pure
(VRT 50/2) room temperature
control .......................................... 11
4.7 Calling up status codes................ 13
5 Care and maintenance .............. 13
5.1 Caring for the product .................. 13
5.2 Maintenance ................................ 13
5.3 Reading maintenance
messages .................................... 13
5.4 Maintaining the pressure of the
heating system............................. 13
5.5 Checking the condensate
discharge pipe and tundish.......... 16
6 Troubleshooting ........................ 16
7 Decommissioning...................... 16
7.1 Temporarily decommissioning
the product................................... 16
7.2 Permanently decommissioning
the product................................... 16
8 Restarting ................................... 16
9 Recycling and disposal............. 17
10 Guarantee and customer
service ........................................ 17
10.1 Guarantee.................................... 17
10.2 Customer service......................... 17
Appendix ............................................... 18
A End user level ............................ 18
A.1 Additional functions...................... 19
B Status codes .............................. 19
C Fault codes/limp home mode
codes .......................................... 20
D Troubleshooting ........................ 20

0020308119_02 Operating instructions 3
1 Safety
1.1 Intended use
The product is intended as a
heat generator for sealed heat-
ing installations and for do-
mestic hot water generation.
Intended use also includes the
following:
–Using the product while ob-
serving the operating instruc-
tions included for the product
and any other installation
components
–Observing all inspection and
maintenance intervals listed in
the instructions
Any other use that is not spe-
cified in these instructions, or
use beyond that specified in this
document, shall be considered
improper use.
Improper use of any kind is
prohibited.
1.2 Qualification
▶Employ only a qualified com-
petent person to install, con-
vert and set the product.
As the end user, you may carry
out all of the work that is de-
scribed in these instructions.
Exception: This product can be
used by children aged from 8
years and above and persons
with reduced physical, sensory
or mental capabilities or lack of
experience and knowledge if
they have been given supervi-
sion or instruction concerning
use of the product in a safe way
and understand the hazards in-
volved. Children must not play
with the product. Cleaning and
user maintenance work must
not be carried out by children
unless they are supervised.
Work that is described in other
instructions must only be car-
ried out by persons who meet
the requirements described
therein.
1.3 General safety
information
The following sections convey
important safety information. It
is essential to read and observe
this information in order to pre-
vent risk of death, risk of injury,
material damage or environ-
mental damage.
1.3.1 Gas
If you smell gas:
▶Avoid rooms that smell of
gas.
▶If possible, open doors and
windows fully and ensure
adequate ventilation.
▶Do not use naked flames (e.g.
lighters, matches).
▶Do not smoke.
▶Do not use any electrical
switches, mains plugs, door-

4Operating instructions 0020308119_02
bells, telephones or other
communication systems in
the building.
▶Close the emergency control
valve or the main isolator.
▶If possible, close the gas
stopcock on the product.
▶Warn other occupants in the
building by yelling or banging
on doors or walls.
▶Leave the building immedi-
ately and ensure that others
do not enter the building.
▶Alert the police and fire bri-
gade as soon as you are out-
side the building.
▶Use a telephone outside the
building to inform the emer-
gency service department of
the gas supply company.
1.3.2 Risk of death from
escaping gas
What to do if you smell gas in
the building:
▶Avoid rooms that smell of
gas.
▶If possible, open doors and
windows fully and ensure
adequate ventilation.
▶Do not use naked flames (e.g.
lighters, matches).
▶Do not smoke.
▶Do not use any electrical
switches, mains plugs, door-
bells, telephones or other
communication systems in
the building.
▶If it is safe to do so, close the
emergency control valve or
the main isolator.
▶If possible, close the gas
stopcock on the product.
▶Warn other occupants in the
building by yelling or banging
on doors or walls.
▶Leave the building immedi-
ately and ensure that others
do not enter the building.
▶Notify the gas supply
company or the Emer-
gency Service Provider
[phone] by tele-
phone once you are outside
of the building.
1.3.3 Flue gas
If you smell flue gas:
▶Open all accessible doors
and windows fully to provide
ventilation.
▶Switch off the product.
▶Contact a competent person.
1.3.4 Subsequent product
modifications
▶Never remove, bridge or
block the safety devices.
▶Do not tamper with any of the
safety devices.
▶Do not damage or remove
any tamper-proof seals on
components.
▶Do not make any changes:
–The product itself

0020308119_02 Operating instructions 5
–to the gas, supply air, water
and electricity supply lines
–to the entire flue system
–to the entire condensate dis-
charge system
–to the expansion relief valve
–to the drain pipework
–to constructional conditions
that may affect the operational
reliability of the product
▶Ensure that there is an evenly
sufficient combustion air sup-
ply.
1.3.5 Material damage
▶Ensure that the combustion
air supply is always free of
fluorine, chlorine, sulphur,
dust, etc.
▶Ensure that no chemical sub-
stances are stored at the in-
stallation site.
▶During a period of frost, en-
sure that the heating install-
ation remains in operation
and that all rooms are heated,
even when you are away.
–If a control is installed,
switch the product on and
off using the control to keep
the frost protection devices
active.
▶If you cannot ensure the oper-
ation, have a competent per-
son drain the heating installa-
tion.
▶Only fill the heating installa-
tion with suitable heating wa-
ter and, in cases of doubt, ask
a competent person about
this.
1.3.6 Legionella
▶Have a competent person in-
form you about the measures
that should be taken to pro-
tect against Legionella in your
installation.
▶Do not set any water temper-
atures below 60 °C without
consulting the competent per-
son first.

6Operating instructions 0020308119_02
2 Notes on the
documentation
▶Always observe all operating instruc-
tions enclosed with the installation com-
ponents.
▶Store these instructions and all other
applicable documents for further use.
These instructions apply for the following
products only:
Product article number
VU 10CS/1-5 (N-GB)
ecoTEC plus 610
0010036009
VU 15CS/1-5 (N-GB)
ecoTEC plus 615
0010036010
VU 20CS/1-5 (N-GB)
ecoTEC plus 620
0010036011
VU 25CS/1-5 (N-GB)
ecoTEC plus 625
0010036012
VU 30CS/1-5 (N-GB)
ecoTEC plus 630
0010036013
VU 35CS/1-5 (N-GB)
ecoTEC plus 635
0010036014
VUW 20/26CS/1-5 (N-GB)
ecoTEC plus 826
0010036015
VUW 25/32CS/1-5 (N-GB)
ecoTEC plus 832
0010036016
VUW 30/36CS/1-5 (N-GB)
ecoTEC plus 836
0010036017
VUW 30/40CS/1-5 (N-GB)
ecoTEC plus 840
0010036018
VUI 30/40CS/1-5 (N-GB)
ecoTEC plus 940
0010036114
Gas Council Numbers
VU 10CS/1-5 (N-GB) ecoTEC
plus 610
41-694-45
VU 15CS/1-5 (N-GB) ecoTEC
plus 615
41-694-46
VU 20CS/1-5 (N-GB) ecoTEC
plus 620
41-694-47
VU 25CS/1-5 (N-GB) ecoTEC
plus 625
41-694-48
VU 30CS/1-5 (N-GB) ecoTEC
plus 630
41-694-49
VU 35CS/1-5 (N-GB) ecoTEC
plus 635
41-694-50
VUW 20/26CS/1-5 (N-GB)
ecoTEC plus 826
47-044-92
VUW 25/32CS/1-5 (N-GB)
ecoTEC plus 832
47-044-93
VUW 30/36CS/1-5 (N-GB)
ecoTEC plus 836
47-044-94
VUW 30/40CS/1-5 (N-GB)
ecoTEC plus 840
47-044-95
VUI 30/40CS/1-5 (N-GB)
ecoTEC plus 940
47-044-96
3 Product description
3.1 Display and control elements
Control
element
Function
–Activate/deactivate standby
mode: Press for less than three
seconds
–Reset button: Press and hold
for more than three seconds to
restart
Setting the desired flow temperat-
ure from the boiler
Setting the desired domestic hot
water temperature from the boiler
–Calling up help
–Calling up the time programme
assistant (control module)
–Go one level back
–Cancelling input
–Calling up the menu
–Back to the main menu
–Calling up the basic display
–Confirming a selection/change
–Saving the set value
Call up chimney sweep mode
(carry out combustion analysis).
For competent persons only.

0020308119_02 Operating instructions 7
Control
element
Function
–Navigating through the menu
structure
–Reducing or increasing the set
value
–Navigating to individual num-
bers and letters
3.2 Displayed symbols
Symbol Meaning
Current burner modulation rate
(display in five levels).
Current system pressure
(display in five levels):
–Permanently on: Filling pres-
sure in the permitted range
–Flashing: Filling pressure
outside the permitted range
Heating mode activated:
–Permanently on: Burner off,
no heat demand
–Flashing: Burner on, heat
demand present
Heating mode is switched off
Domestic hot water generation
activated:
–Permanently on: Burner off,
no heat demand
–Flashing: Burner on, heat
demand present
Product with integrated do-
mestic hot water generation
or product with connected
domestic hot water cylinder
Comfort mode activated:
–Permanently on: Comfort
mode is activated
–Flashing: Burner on, comfort
mode on
Installer level active
Display locked
Connected to the system con-
trol
Connection to the Vaillant
server established
Symbol Meaning
Product is busy with a task.
Setting the time:
–Permanently on: Time is set
–Flashing: The time must be
reset
Warning
Fault in the product:
Appears instead of the basic
display, may be an explanatory
plain text display.
Limp home mode:
Appears instead of the basic
display, may be an explanatory
plain text display.
Maintenance required:
You can find more information
in code I.XXX.
Maintenance required:
Appears instead of the basic
display, may be an explanatory
plain text display.
3.3 Serial number
The serial numbers are located on the
underside of the front panel and on the
data plate.
The 3rd to 6th digits provide the produc-
tion date (year/week), the 7th to 16th digit
provide the article number for the product.
3.4 CE marking
The CE marking shows that the products
comply with the basic requirements of the
applicable directives as stated on the de-
claration of conformity.
The declaration of conformity can be
viewed at the manufacturer's site.

8Operating instructions 0020308119_02
3.5 UKCA mark
The UKCA marking shows that the
products comply with the basic require-
ments of the applicable directives as
stated on the declaration of conformity.
The declaration of conformity can be
viewed at the manufacturer's site.
3.6 Hot Water Association
Vaillant is a full member of the Hot Water
Association and promotes the scheme
in association with its cylinder range.
Details are available on the web site
www.vaillant.co.uk
3.7 Benchmark
Vaillant is a licensed member of the
Benchmark Scheme which aims to im-
prove the standards of installation and
commissioning of domestic heating and
hot water systems in the UK and to en-
courage regular servicing to optimise
safety, efficiency and performance.
Benchmark is managed and promoted
by the Heating and Hotwater Industry
Council. For more information visit
www.benchmark.org.uk.
▶Please ensure that the installer has fully
completed the Benchmark Checklist on
the inside back pages of the installation
instructions supplied with the product
and that you have signed it to say that
you have received a full and clear ex-
planation of its operation. The installer
is legally required to complete a com-
missioning checklist as a means of
complying with the appropriate Build-
ing Regulations (England and Wales).
All installations must be notified to Local
Area Building Control either directly or
through a Competent Persons Scheme.
A Building Regulations Compliance Certi-
ficate will then be issued to the customer
who should, on receipt, write the Notifica-
tion Number on the Benchmark Checklist.
This product should be serviced regularly
to optimise its safety, efficiency and per-
formance. The service engineer should
complete the relevant Service Record on
the Benchmark Checklist after each ser-
vice.
The Benchmark Checklist will be required
in the event of any warranty.
4 Operation
4.1 Operating concept
Control elements that are lit up in colour
can be selected.
Adjustable values and list entries can be
changed using the scrollbar. Briefly tap on
the top and bottom end of the scrollbar in
order to implement changes.
You must confirm a change to a value.
Only then is the new setting saved. You
have to press flashing control elements
again to confirm.
Control elements that are lit up in white are
active.
The menu and the control elements are
dimmed after 60 seconds in order to save
energy. The status display is shown after
another 60 seconds.
You can find additional assistance for the
control elements under MAIN MENU →
INFORMATION →Control elements.

0020308119_02 Operating instructions 9
4.1.1 Basic display
If the status display is shown, press to
call up the basic display.
In the basic display, you can set the de-
sired domestic hot water temperature and
flow temperature/desired temperature
(desired temperature only available for
products with a control module).
The flow temperature is the temperature
at which the heating water leaves the heat
generator (e.g. 65 °C).
The desired temperature is the temper-
ature that is actually desired for the living
room (e.g. 21 °C).
Press to set the temperature for do-
mestic hot water mode.
Press to set the temperature for heat-
ing mode.
Further settings for heating mode and do-
mestic hot water mode are described in
the relevant sections.
If the basic display is shown, press to
call up the menu.
The functions that are available in the
menu depend on whether a system control
is connected to the product. If you have
connected a system control, the settings
for heating mode must be available in the
system control. (→System control operat-
ing instructions)
You can find additional assistance for the
navigation under MAIN MENU →INFORM-
ATION →Menu introduction.
If there is an error message present, the
basic displays switches to the error mes-
sage.
Note
If a code request appears after you
press , your competent person
has locked access to the control
panel in order to prevent settings
from being accidentally changed.
Contact your competent person.
4.1.2 Operating levels
If the basic display is shown, call up the
menu in order to display the end user
level.
In the end user level, you can change
and individually adapt the settings for the
product. The table in the appendix lists the
menu items and setting options that can
be selected. (→Appendix A)
A timer is built into the boiler for the heat-
ing circuit but is only activated and vis-
ible with the use of a Vaillant sensoROOM
pure (VRT 50/2) control.
The installer level must only be operated
by persons with expertise and is therefore
protected by a code.
4.2 Setting the language
1. Press twice.
2. Navigate to the bottom menu item
(XXX) and confirm by pressing
.
3. Select the third menu item and con-
firm by pressing .
4. Select the first menu item and confirm
by pressing .
5. Select the required language and con-
firm by pressing .

10 Operating instructions 0020308119_02
4.3 Activating/deactivating the
button lock
1. Call up MAIN MENU →SETTINGS →
Button lock.
2. Confirm by pressing .
–The button lock is activated.
3. To deactivate the button lock, press
and hold for four seconds.
4.4 Heating mode
In heating mode, the rooms are heated up
in accordance with your settings.
4.4.1 Setting the flow temperature
Validity: Product without connected sensoROOM
pure (VRT 50/2) AND Product without system control
▶From the basic display, press .
◁The flow temperature that has
already been set is shown in the
display.
▶Set the desired flow temperature.
Validity: Product with connected sensoROOM pure
(VRT 50/2) OR Product with system control
▶Set the desired temperature on the
control or room temperature control;
see operating and installation instruc-
tions for the control or room temperat-
ure control.
4.4.2 Permanently switching off
heating mode (summer mode)
Validity: Product without connected sensoROOM
pure (VRT 50/2)
▶From the basic display, press for
at least three seconds.
◁Heating mode is switched off.
◁The symbol for heating mode
is shown as deactivated in the
display.
Validity: Product with connected sensoROOM pure
(VRT 50/2)
▶Set the lowest target room temperat-
ure on the room temperature control;
see operating and installation instruc-
tions for the room temperature con-
trol.
◁Heating mode is switched off.
Note
If the sensoROOM pure
(VRT 50/2) room temperature
control is connected, you
cannot set the desired temper-
ature on the product's control
panel.
4.5 DHW mode
Validity: Product with integrated hot water genera-
tion OR Product with connected domestic hot water
cylinder
In domestic hot water mode, the potable
water is heated to the required domestic
hot water temperature.
4.5.1 Setting the domestic hot water
temperature
1. From the basic display, press .
2. Set the required domestic hot water
temperature.
4.5.2 Switching off the domestic hot
water mode
Validity: Product with connected domestic hot wa-
ter cylinder OR Product with integrated hot water
generation and shift-load cylinder
▶Starting from the basic display, press
for at least five seconds.
◁The domestic hot water mode is
switched off.
4.5.3 Switching comfort mode
on/off
Note
Comfort mode keeps the domestic
hot water generation ready and
supplies hot water at the desired
temperature without you having to
wait for the heat-up time.