1.1 Action-related warnings
Classification of action-re-
lated warnings
The action-related warnings
are classified in accordance
with the severity of the possible danger using the following
warning signs and signal words:
Warning symbols and signal
words
Danger!
Imminent danger to life
or risk of severe personal
injury
Danger!
Risk of death from electric
shock
Warning.
Risk of minor personal
injury
Caution.
Risk of material or environmental damage
1.2 Intended use
There is a risk of injury or death
to the user or others, or of damage to the product and other
property in the event of improper use or use for which it
is not intended.
The product is intended as a
heat generator for closed cent-
ral heating installations and for
hot water generation.
Intended use includes the following:
– observance of the operating
instructions included for the
product and any other system
components
– compliance with all inspection
and maintenance conditions
listed in the instructions.
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 supervision or instruction concerning
use of the product in a safe way
and understand the hazards involved. Children must not play
with the product. Cleaning and
user maintenance work must
not be carried out by children
unless they are supervised.
Any other use that is not specified in these instructions, or
use beyond that specified in this
document shall be considered
improper use. Any direct commercial or industrial use is also
deemed to be improper.
Caution.
Improper use of any kind is
prohibited.
0020224356_00 HOME Operating instructions3
1 Safety
1.3 General safety
information
1.3.1 Installation by skilled
tradesmen only
The installation, inspection,
maintenance and repair of the
product, as well as the gas ratio
settings, must only be carried
out by a competent person.
1.3.2 Danger caused by
improper operation
Improper operation may present
a danger to you and others, and
cause material damage.
▶ Carefully read the enclosed
instructions and all other applicable documents, particularly the "Safety" section and
the warnings.
1.3.3 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, doorbells, 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 isol-
ator cock 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 com-
pany or National Grid Transco
+44 (0) 800 111999 by telephone from outside of the
building.
1.3.4 Risk of death due to a
blocked or leaking flue
gas pipe
What to do if you smell flue gas
in the property:
▶ Open all accessible doors
and windows fully to provide
ventilation.
▶ Switch off the product.
▶ Inform a competent person.
1.3.5 Risk of death from
escaping flue gas
If you operate the product with
an empty condensate siphon,
flue gas may escape into the
room air.
4Operating instructions HOME 0020224356_00
Safety 1
▶ In order to operate the
product, ensure that the condensate siphon is always full.
1.3.6 Risk of death due to
explosive and flammable
materials
▶ Do not use or store explosive
or flammable materials (e.g.
petrol, paper, paint) in the installation room of the product.
1.3.7 Risk of death due to lack
of safety devices
A lack of safety devices (e.g.
expansion relief valve, expansion vessel) can lead to potentially fatal scalding and other
injuries, e.g. due to explosions.
▶ Ask a competent person
to explain how the safety
devices work and where they
are located.
1.3.8 Risk of death due
to changes to the
product or the product
environment
▶ Never remove, bridge or
block the safety devices.
▶ Do not alter the safety
devices in any way.
▶ Do not damage or remove
any seals on components.
▶ Do not make any changes:
– The product itself
– to the gas, air, water and
electricity supplies
– to the entire flue gas install-
ation
– to the entire condensate
drain system
– to the expansion relief valve
– to the drain lines
– to constructional condi-
tions that may affect the
operational reliability of the
product
1.3.9 Risk of injury and
material damage due to
maintenance and repairs
carried out incorrectly or
not carried out at all
▶ Never attempt to carry out
maintenance work or repairs
on your product yourself.
▶ Faults and damage should
be immediately rectified by a
competent person.
▶ Adhere to the maintenance
intervals specified.
1.3.10 Risk of corrosion
damage due to
unsuitable combustion
and room air
Sprays, solvents, chlorinated
cleaning agents, paint, adhesives, ammonia compounds,
dust or similar substances may
lead to corrosion on the product
and in the air/flue pipe.
0020224356_00 HOME Operating instructions5
1 Safety
▶ Ensure that the supply of
combustion air is always free
of fluorine, chlorine, sulphur,
dust, etc.
▶ Ensure that no chemical sub-
stances are stored at the installation site.
1.3.11 Risk of material
damage caused by
frost
▶ Ensure that the heating in-
stallation always remains in
operation during freezing conditions and that all rooms are
sufficiently heated.
▶ If you cannot ensure the op-
eration, have a competent
person drain the heating installation.
6Operating instructions HOME 0020224356_00
Notes on the documentation 2
2Notes on the
documentation
2.1 Observing other applicable
documents
▶ You must observe all operating instruc-
tions enclosed with the system components.
2.2 Storing documents
▶ Keep this manual and all other applic-
able documents safe for future use.
2.3 Applicability of the
instructions
These instructions apply only to:
Product article number
Article number
HOME SYSTEM 12 -A
(H-GB)
HOME SYSTEM 15 -A
(H-GB)
HOME SYSTEM 18 -A
(H-GB)
HOME SYSTEM 25 -A
(H-GB)
001001993441-044-94
001001993541-044-95
001001993641-044-96
001001993741-044-97
These products are only designed for natural gas systems.
Gas Council
Number
3Product description
3.1 CE label
The CE label shows that the products
comply with the basic requirements of the
applicable directives as stated on the identification plate.
The declaration of conformity can be
viewed at the manufacturer's site.
3.2 Serial number
The serial number is on the identification
plate on the underside of the product.
3.3 Information on the
identification plate
The identification plate is mounted on the
underside of the product in the factory.
The identification plate keeps record of
the country in which the product is to be
installed.
Information
on the identification plate
Serial number For quality control purposes;
HOME SYSTEM
XX, Gxx –
xx mbar
(x kPa)
Meaning
Barcode with serial number
3rd and 4th digits = year of
production
For quality control purposes;
5th and 6th digits = week of
production
For identification purposes;
7th to 16th digits = product
article number
For quality control purposes;
17th to 20th digits = place of
manufacture
Product description
Gas group and gas connection pressure as set at the
factory
0020224356_00 HOME Operating instructions7
3 Product description
1
1
2
34
5
Information
on the identification plate
Cat.Approved gas category
Condensing
technology
Type: Xx3(x)Permissible flue gas connec-
PMSMaximum water pressure in
PMWMaximum water pressure in
V/HzElectric connection
WMax. electrical power con-
IPLevel of protection
PnNominal heat output range
PncNominal heat output range
PNominal heat output range
QnNominal heating load range
QnwNominal heating load range
T
max.
NOxNOx class for the product
Code (DSN)Specific product code
Meaning
Efficiency class of the boiler
in accordance with EC Directive 92/42/EEC
tions
heating mode
hot water handling mode
sumption
Heating mode
Hot water generation
in heating mode
in heating mode (condensing
technology)
in hot water handling mode
in heating mode
in hot water handling mode
Max. flow temperature
→ "CE label" section
3.4 Product design
1Control elements
3.5 Overview of the operator
control elements
Read the instructions.
→ "Recycling and disposal"
section
GC no.Gas council number
8Operating instructions HOME 0020224356_00
1Display
2
3
button
button
4
button
5
button
Product description 3
1
2
3
3.6 Description of the display
1Operating in-
formation
2Active operating
mode, selecting
and confirming
the operating
mode
SymbolMeaning
3Display showing
the current heating flow temperature, the filling
pressure in the
heating installation, the operating mode or a
fault code
Burner operating correctly
– Burner on
Heating installation filling
pressure
– Permanently on: Filling
pressure in the permitted
range.
– Flashing display: Filling
pressure is outside of the
permissible range or the
purging function has been
activated.
DHW mode
– Permanently on: Hot wa-
ter activated
– Flashing: Burner on when
the domestic hot water
cylinder is in reheating
mode
Hot water saving mode
– Hot water temperature <
50 °C
– Normal operating temper-
ature
SymbolMeaning
Heating mode
– Permanently on: Heating
mode activated
– Flashing: Burner on in
heating mode
Display flashing:
– Switching on the product
– Fault
Setting confirmed
/
OFF– Appears when the
Fault in the product
– Appears instead of the
basic display.
product goes into standby
mode.
3.7 Description of button
functions
ButtonMeaning
– Selecting the operating mode
– Confirm the operating mode
– Confirm setting
– Increase the display contrast
– Setting the hot water temperat-
or
ure
– Setting the heating flow tem-
perature
– Increase or decrease the selec-
ted setting
– Increase the display contrast
– Activate the product: On/off
(standby)
– Reset the product
Adjustable values flash on the display.
You must confirm any change to a value.
Only then is the new setting saved.
If you do not press any buttons for five
seconds, the displays switches back to
the basic display.
If you do not press any buttons for one
minute, the display contrast decreases.
0020224356_00 HOME Operating instructions9
4 Operation
12
3.8 Operating levels
The product has two operating levels:
– The operator level shows the most im-
portant information and offers set-up
options which do not require any special
prior knowledge.
– Specialised knowledge is required in or-
der to use the installer level (access for
competent persons). This is therefore
protected by an access code.
Operator level – overview (→ Page 15)
4Operation
4.1 Starting up the product
4.1.1 Opening the isolator devices
Conditions: The competent person who installed
the unit will explain where the isolator devices are
and how to handle them.
▶ Ensure that the gas isolator cock is fully
open.
▶ Ensure that the stop cocks in the heat-
ing installation's flow and return are
open.
▶ Ensure that the cold water stop cock is
open.
4.1.2 Starting up the product
4.2 Basic display
The filling pressure in the heating installation and the operating mode are shown in
the display's basic display.
To return to the basic display:
– Wait more than five seconds without
pressing any buttons.
If a fault message is present, the basic
display switches to the fault code.
4.3 Checking the heating system
pressure
1. Once a month, check that the pressure
in the central heating system, which
is displayed on the user interface,
is between 0.1 MPa and 0.15 MPa
(1.0 bar and 1.5 bar).
◁ If the filling pressure is correct, no
action needs to be taken.
▽ If the filling pressure is too low, add
more water to the heating installation.
Note
If the heating flow temperature
is shown in the display, press
and hold theandbuttons
▶ Press the (2) button.
◁ When the unit is switched on, the
"Basic display" is shown in the
display (1).
2. Fill the heating installation. (→ Page 11)
at the same time for longer than
five seconds, or temporarily
deactivate heating mode in
order to display the pressure.
10Operating instructions HOME 0020224356_00
Operation 4
4.4 Filling the heating installation
Caution.
Risk of material damage due
to heating water that is extremely calciferous or corrosive or contaminated by chemicals.
Unsuitable tap water damages
the seals and diaphragms,
blocks components in the
product and heating installation
through which the water flows
and causes noise.
▶ Only fill the heating install-
ation with suitable heating
water.
▶ In case of doubt, ask a com-
petent person for details.
Note
The competent person is responsible for filling the heating installation the first time, any subsequent
top-ups and the water quality.
The operator alone is responsible for topping up the water in the
heating installation.
1. Open all radiator valves (thermostatic
radiator valves) of the heating installation.
2. Slowly open the filling cock, as shown
to you by the competent person.
3. Fill with water until the required filling
pressure is reached.
4. Check the filling pressure in the
display.
5. Close the filling cock after filling.
4.5 Selecting the operating mode
Note
The unit is always activated with
the preselected operating mode.
▶ Pressrepeatedly until the display
shows the required operating mode.
SymbolOperating mode
Heating + hot water
+
Heating only
Hot water only
‒No requirement
4.6 Setting the hot water
temperature
Conditions: The temperature is controlled via the
domestic hot water cylinder's thermostat.
▶ Set the hot water temperature on the
controller.
Note
If you press theorbutton,
the display shows thesymbol.
Conditions: The temperature is controlled via the
domestic hot water cylinder's temperature sensor.
▶ Set the hot water temperature on the
controller.
4.7 Setting the heating flow
temperature
Conditions: Temperature controlled by the boiler,
with heating mode activated
▶ Set the heating flow temperature on the
boiler (→ Page 12).
Note
The competent person may
have adjusted the maximum
possible temperature.
0020224356_00 HOME Operating instructions11
4 Operation
Conditions: Temperature controlled by the control-
ler, with heating mode activated
▶ Set the maximum heating flow temper-
ature on the boiler (→ Page 12).
▶ Set the room temperature on the con-
troller.
◁ The actual heating flow temperature
is set automatically by the controller.
Conditions: Outside temperature sensor connected
to the boiler, with heating mode activated
▶ When you press the,orbut-
ton.
◁ The display shows the heating flow
temperature calculated by the boiler.
◁ The actual heating flow temperature
is set automatically by the boiler.
4.8 Product settings
Note
The sequence in which the available settings are shown depends
on the operating mode selected.
If the Domestic hot water + Heat-ing operating mode is selected,
the hot water temperature must be
confirmed in order to set the flow
temperature of the heating.
1. Press theorbutton to set the temperature.
2. Press thebutton to confirm.
4.9 Switching the product to
standby mode
▶ Press thebutton for less than three
seconds.
◁ Once the requirement currently in
use has finished, the display will
show OFF and go out.
◁ The product is now in standby mode.
◁ The product's frost protection func-
tion is activated.
◁ The main power supply is not inter-
rupted. The product continues to be
supplied with power.
4.10 Frost protection
4.10.1 The product's frost
protection function
The frost protection function switches on
the boiler and the pump as soon as the
protection temperature in the heating circuit is reached.
– Protection temperature: 12 ℃
The pump stops once the minimum water temperature in the heating circuit is
reached.
– Minimum water temperature: 15 ℃
If the burner ignition temperature in the
heating circuit is reached, the burner
switch is switched on and continues
to operate until the burner anti-cycling
temperature is reached.
The hot water circuit (cold and hot water)
is not protected by the boiler.
Frost protection for the system can only be
guaranteed by the boiler.
A controller is required to control the temperature of the system.
4.10.2 Frost protection for the
system
Note
Ensure that the product's power
and gas supply are working correctly.
Conditions: If you are away from home for several
days, Without controller
▶ Switch the product to standby mode.
(→ Page 12)
12Operating instructions HOME 0020224356_00
Troubleshooting 5
Conditions: If you are away from home for several
days, With controller
▶ Program the number of days you will
be away in the controller to activate the
frost protection devices.
Conditions: If you are away from home for a pro-
longed period
▶ Contact a qualified competent person,
who can completely drain the system or
protect the heating circuit by adding a
special frost protection agent for heating
installations.
5Troubleshooting
5.1 Detecting and rectifying faults
▶ If problems occur whilst operating the
product, you can carry out certain selfchecks with the aid of the table in the
appendix.
Troubleshooting (→ Page 15)
▶ If the product still does not function
without problems after the checks have
been carried out using the table, contact your competent person to rectify
the problem.
5.2 Fault codes in the display
Fault codes have priority over all other displays. If several faults occur at the same
time, the corresponding codes are displayed alternately for two seconds each.
▶ If your product displays a fault code
(F.xx), contact a competent person.
6Care and maintenance
6.1 Maintenance
An annual inspection of the product carried
out by a competent person is a prerequisite for ensuring that the product is permanently ready and safe for operation, reliable,
and has a long working life.
6.2 Caring for the product
Caution.
Risk of material damage
caused by unsuitable cleaning agents.
▶ Do not use sprays, scouring
agents, detergents, solvents
or cleaning agents that contain chlorine.
▶ Clean the casing with a damp cloth and
a little solvent-free soap.
6.3 Checking the condensate
drain pipework and tundish
The condensate drain pipework and tundish must always be penetrable.
▶ Regularly check the condensate drain
pipework and tundish for faults and,
particularly, for blockages.
You must not be able to see or feel any
obstructions in the condensate drain pipework and tundish.
▶ If you notice a fault, have it rectified by
a competent person.
0020224356_00 HOME Operating instructions13
7 Decommissioning
7Decommissioning
7.1 Temporarily decommissioning
the product
▶ Temporarily decommission the product
only if there is no risk of frost.
▶ Switch off the product via the main
switch provided on-site.
◁ The display goes out.
▶ When decommissioning for an exten-
ded period (e.g. holiday), you should
also close the gas isolator cock and the
cold water stop cock.
7.2 Permanently
decommissioning the product
▶ Have a competent person permanently
decommission the product.
8Recycling and disposal
▶ The competent person who installed
your product is responsible for the disposal of the packaging.
If the product is identified with this
symbol:
▶ In this case, do not dispose of the
product with the household waste.
▶ Instead, hand in the product to a collec-
tion centre for old electrical or electronic
appliances.
If the product contains batteries that
are marked with this symbol, these batteries may contain substances that are
hazardous to human health and the environment.
▶ In this case, dispose of the batteries at
a collection point for batteries.
9Guarantee and customer
service
9.1 Guarantee
– Two year guarantee
Vaillant provides this appliance with a
parts and labour guarantee against defects
that may occur within twenty-four months
of the installation date. For the 2nd year of
the guarantee to be valid an annual service must be carried out by a competent
person approved at the time by the Health
and Safety Executive one year after installation. The cost of this annual service is not
included in the guarantee.
– Registering with us
Registration is simple. Just complete the
Guarantee Registration Card and return to
Vaillant within 30 days of installation. Your
details will then be automatically registered
within the Vaillant scheme.
– Immediate help
If your Vaillant boiler develops a fault your
first action should be to contact your installer, as his professional assessment is
needed under the terms of our Guarantee.
If you are unable to contact your installer,
phone Vaillant Service Solutions: 0870
6060 777
9.2 Customer service
To ensure regular servicing, it is strongly
recommended that arrangements are
made for a Maintenance Agreement.
Please contact Vaillant Service Solutions
for further details.
The gas isolator cock installed on-site
and/or the gas isolator cock on the
product is closed.
The cold water stop cock is closed.Open the cold water stop cock.
The power supply in the building is disconnected.
The product is switched off.Switch on the product (→ "Switch-
The heating flow temperature or hot
water temperature has been set too
low.
The system pressure is insufficient.
Low water pressure in the heating installation (fault code: F.22).
The system pressure is too high.Purge a radiator in order to re-
There is air in the heating installation.Purging the radiators
Open both gas isolator cocks.
Check the fuse in the building. The product automatically
switches on after the power
supply is restored.
ing on the product" section).
Set the heating flow temperature and hot water temperature (→
"Setting the heating flow temperature" section/→ "Setting the hot
water temperature" section).
Fill the heating installation (→
"Filling the heating installation"
section).
If the pressure drops frequently,
contact your competent person
about this.
duce the pressure in the heating
installation, or contact your competent person about this.
If the problem occurs again: Inform the competent person
tings
0020224356_00 HOME Operating instructions15
Appendix
FaultCauseMeasure
Product does not
start up:
– No hot water
– Heating does
not heat up
Hot water generation functioning
correctly; heating
does not start up.
After three successive failed ignition
attempts, the system switches to fault
mode (fault code: F.28).
The external controller is not set correctly.
Press thebutton. The product
carries out a new ignition attempt.
If the ignition problem is not rectified after three fault clearance
attempts, contact a competent
person.
Set the external controller correctly (→ Controller operating instructions).