Vaillant ecoTEC pro VUW 6/5-3 Series User manual

en Installation and maintenance instructions
ecoTEC pro
VUW ..6/5-3
0020244995_04 - 29.07.2020

2Installation and maintenance instructions ecoTEC pro 0020244995_04
Installation and maintenance
instructions
Contents
1 Safety .................................................................... 4
1.1 Intended use .......................................................... 4
1.2 Qualification ........................................................... 4
1.3 General safety information .................................... 4
1.4 Regulations (directives, laws, standards) .............. 6
1.5 List of relevant standards for Great Britain and
Ireland.................................................................... 6
2 Guarantee and Customer Service...................... 7
3 Technical data...................................................... 8
4 Notes on the documentation ............................ 11
5 Product description........................................... 11
5.1 CE marking .......................................................... 11
5.2 Energy Saving Trust Endorsed Products ............ 11
5.3 Hot Water Association ......................................... 11
5.4 Information on the identification plate.................. 11
5.5 Serial number ...................................................... 12
5.6 Product design..................................................... 12
5.7 Safety Devices..................................................... 12
6 Set-up.................................................................. 13
6.1 Checking the scope of delivery............................ 13
6.2 Dimensions .......................................................... 13
6.3 Installation site ..................................................... 14
6.4 Minimum clearances............................................ 14
6.5 Compartment Ventilation ..................................... 14
6.6 Air/flue pipe.......................................................... 14
6.7 Using the installation template............................. 18
6.8 Wall-mounting the product................................... 18
6.9 Removing/installing the front casing.................... 18
6.10 Removing/installing the side section ................... 19
7 Installation.......................................................... 20
7.1 Installation requirements ..................................... 20
7.2 Installing the gas connection ............................... 20
7.3 Checking the gas line for leak-tightness.............. 20
7.4 Installing the hot and cold water connection........ 20
7.5 Connecting the heating flow and heating
return ................................................................... 21
7.6 Connecting the drain pipework for the
expansion relief valve .......................................... 21
7.7 Connecting the condensate discharge pipe ........ 21
7.8 Flue installation.................................................... 23
7.9 Electrical installation ............................................ 24
8 Operation............................................................ 26
8.1 Operating concept ............................................... 26
8.2 Installer level overview......................................... 26
8.3 Calling up the installer level................................. 26
8.4 Live Monitor (status codes) ................................. 26
8.5 Setting the hot water temperature ....................... 26
9 Start-up ............................................................... 27
9.1 Carrying out the initial start-up............................. 27
9.2 Checking and treating the heating water/filling
and supplementary water .................................... 27
9.3 Filling the condensate trap .................................. 28
9.4 Switching the product on and off ......................... 28
9.5 Using check programmes.................................... 28
9.6 Preventing low water pressure ............................ 28
9.7 Flushing the heating installation for the first
time ("cold") ......................................................... 28
9.8 Filling the heating installation .............................. 28
9.9 Purging the heating installation ........................... 29
9.10 Filling and purging the hot water system ............. 29
9.11 Gas inspection ..................................................... 29
9.12 Thoroughly flushing the heating installation
("hot")................................................................... 31
9.13 Checking leak-tightness ...................................... 31
10 Adapting the unit to the heating
installation.......................................................... 31
10.1 Calling up diagnostics codes ............................... 31
10.2 Burner anti-cycling time ....................................... 31
10.3 Setting the maintenance interval ......................... 32
10.4 Setting the pump output....................................... 32
10.5 Setting the bypass valve...................................... 32
11 Handing over to the end user........................... 33
12 Inspection and maintenance ............................ 34
12.1 Complete Service Interval Record section .......... 34
12.2 Using original seals.............................................. 34
12.3 Inspection and maintenance................................ 34
12.4 Preparing the maintenance work......................... 34
12.5 Removing the compact thermal module .............. 34
12.6 Cleaning the heat exchanger............................... 35
12.7 Checking the burner ............................................ 35
12.8 Cleaning the condensate trap.............................. 35
12.9 Cleaning the filter in the cold water inlet.............. 35
12.10 Installing the compact thermal module ................ 36
12.11 Draining the product ............................................ 36
12.12 Checking the pre-charge pressure for the
internal expansion vessel .................................... 36
12.13 Checking the filling pressure of the heating
installation............................................................ 36
12.14 Checking the quality of the heating water............ 36
12.15 Completing inspection and maintenance work .... 36
12.16 Checking the product for leak-tightness .............. 37
13 Troubleshooting ................................................ 37
13.1 Checking service messages................................ 37
13.2 Eliminating faults.................................................. 37
13.3 Calling up and clearing the fault memory ............ 37
13.4 Resetting parameters to factory settings ............. 37
13.5 Preparing the repair work .................................... 37
13.6 Replacing defective components......................... 37
13.7 Completing repair work........................................ 39
13.8 Checking the product for leak-tightness .............. 39
14 Decommissioning.............................................. 39
14.1 Temporarily decommissioning the product.......... 39
14.2 Permanently decommissioning the product......... 39
15 Recycling and disposal..................................... 39
Appendix ............................................................................ 40
A Inspection and maintenance work................... 40

0020244995_04 ecoTEC pro Installation and maintenance instructions 3
B Overview of diagnostics codes........................ 41
C Status codes –Overview .................................. 45
D Overview of fault codes .................................... 46
E Check programmes –Overview ....................... 48
F Wiring diagrams................................................. 49
F.1 Product connection diagram with integrated
hot water generation............................................ 49
G Commissioning Checklist................................. 50
H Commissioning Flow Chart .............................. 54
Index ................................................................................... 55

4Installation and maintenance instructions ecoTEC pro 0020244995_04
1 Safety
1.1 Intended use
The product is intended as a heat generator
for sealed heating installations and for do-
mestic hot water generation.
Improper use of any kind is prohibited.
Intended use also includes the following:
–use of the product only in mobile homes
that are made, transported once and per-
manently situated in Great Britain and Ire-
land. After the transportation of the mo-
bile home to its destination the complete
product must be checked for leak-tightness
again
–validity of the product only for Great Britain
and Ireland and for the gas types in Great
Britain and Ireland as listed on the data
plate
–Installing and operating the product only
in conjunction with accessories for the
air/flue pipe which are listed in the other
applicable documents and comply with the
type of unit
–Using the product while observing the ac-
companying operating, installation and
maintenance instructions for the product
along with all other components of the in-
stallation
–Installing and setting up the product while
observing the product and system ap-
proval
–Observing all inspection and maintenance
conditions listed in the instructions
–Installing while observing the IP code
The following is classed as improper use:
–Using the product in vehicles, such as mo-
bile homes or caravans. Units that are not
classed as vehicles are those that are in-
stalled in a fixed and permanent location
(known as "fixed installation").
–Any direct use in industrial or commercial
processes
–Any use other than those described in
these instructions and any use that goes
beyond what is described here
1.2 Qualification
The person carrying out the work described
here must have completed professional train-
ing. The competent person must demon-
strably have all of the knowledge, skills and
capabilities that are required in order to carry
out the work mentioned below.
The following work must only be carried out
by competent persons who are sufficiently
qualified to do so:
–Set-up
–Dismantling
–Installation
–Start-up
–Inspection and maintenance
–Repair
–Decommissioning
▶Proceed in accordance with current tech-
nology.
▶Use the correct tool.
The above-mentioned work must always only
be carried out by persons with sufficient qual-
ifications.
This product can be used by children over
eight years old and also by persons with lim-
ited physical, sensory or mental capabilities
or insufficient experience and/or knowledge if
they are supervised or have been provided
with instructions on how to safely use the
product, and they understand the risks res-
ulting from using the product. Children must
not play with the product. Cleaning and user
maintenance work must not be carried out by
children unless they are supervised.
1.3 General safety information
The following sections convey important
safety information. It is essential to read and
observe this information in order to prevent
risk of death, risk of injury, material damage
or environmental 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.

0020244995_04 ecoTEC pro Installation and maintenance instructions 5
▶Do not use any electrical switches, mains
plugs, doorbells, telephones or other com-
munication 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 immediately and ensure
that others do not enter the building.
▶Alert the police and fire brigade, and in-
form the emergency service department of
the gas supply company as soon as you
are outside the building.
1.3.2 Flue gas
Flue gases may cause poisoning, while hot
flue gases may also cause burns. Flue gases
must therefore never be allowed to escape
uncontrollably.
What to do if you smell flue gas in the prop-
erty:
▶Open all accessible doors and windows
fully to provide ventilation.
▶Switch off the product.
▶Check the flue gas routes in the product
and the flue gas diversions.
To prevent flue gas exit:
▶Only operate the product if the air/flue pipe
has been completely installed.
▶With the exception of short periods for
testing purposes, only operate the product
when the front casing is installed and
closed.
▶In order to operate the product, ensure that
the condensate siphon is always full.
–Water seal level for units with condens-
ate siphon (third-party accessory):
≥200 mm
To ensure that the seals are not damaged:
▶Instead of grease, use only water or com-
mercially available soft soap to aid installa-
tion.
1.3.3 Electricity
The power supply terminals L and N remain
live.
To prevent electric shocks, proceed as fol-
lows before working on the product:
▶Disconnect the product from the power
supply by switching off all power supplies
at all poles (electrical partition with a con-
tact gap of at least 3 mm, e.g. fuse or cir-
cuit breaker) or remove the mains plug (if
present).
▶Secure against being switched back on
again.
▶Wait at least three minutes until the con-
densers have discharged.
▶Check that there is no voltage.
1.3.4 Weight
To prevent injuries when transporting the
product:
▶Make sure that the product is transported
by at least two people.
To prevent material damage to the flexible
gas pipe:
▶Never suspend the compact thermal
module on the flexible gas pipe.
1.3.5 Explosive and flammable substances
To prevent explosions and fire:
▶Do not use the product in storage rooms
that contain explosive or flammable sub-
stances (such as petrol, paper or paint).
1.3.6 High temperatures
To prevent burns:
▶Only carry out work on components once
they have cooled down.
To prevent material damage that is caused
by heat transfer:
▶Only solder connectors if the connectors
are not yet screwed to the service valves.
1.3.7 Heating water
Both unsuitable heating water and air in the
heating water may cause material damage to
the product and in the heat generator circuit.
▶Check the quality of the heating water.
(→Page 27)

6Installation and maintenance instructions ecoTEC pro 0020244995_04
▶If you use non-diffusion-tight plastic pipes
in the heating installation, ensure that no
air gets into the heat generator circuit.
1.3.8 Neutralisation device
To prevent contamination of the waste water:
▶Check whether a neutralising unit must
be installed in accordance with national
regulations.
▶Observe local regulations on neutralising
condensate.
1.3.9 Frost
To prevent material damage:
▶Do not install the product in rooms prone
to frost.
1.3.10 Safety devices
▶Install the necessary safety devices in the
installation.
1.3.11 Risk of death from leaks if the
product is installed below ground
level
Liquid gas accumulates at floor level. If the
product is installed below ground level, liquid
gas may accumulate at floor level if there
are any leaks. In this case, there is a risk of
explosion.
▶Make sure that liquid gas cannot escape
from the product or the gas pipe under any
circumstances.
1.4 Regulations (directives, laws,
standards)
▶Observe the national regulations, stand-
ards, directives, ordinances and laws.
1.5 List of relevant standards for Great
Britain and Ireland
▶Observe the national regulations, stand-
ards, directives, ordinances and laws.
You can find a list of relevant standards at:
https://www.vaillant.co.uk/standards

0020244995_04 ecoTEC pro Installation and maintenance instructions 7
2 Guarantee and Customer Service
Thank you for installing a new Vaillant appliance in your home.
Vaillant appliances are manufactured to the very highest standard so we are pleased to offer our
customers a comprehensive guarantee.
To maintain your guarantee, the boiler must be serviced annually by a competent person who
holds the required qualifications in accordance with the rules in force of the country where the
product is installed and in accordance with the manufactures recommendations.
We recommend you complete your guarantee registration as soon as possible.
Guarantee Registration
Sales Support:
Telephone: [phone]
Technical Enquiries:
Telephone: [phone]
Email: [e-mail]
General Enquiries:
Telephone: [phone]
Training Enquiries:
Telephone: [phone]
Email: [e-mail]
Spares Enquiries:
Telephone: [phone]
To register your Vaillant appliance visit:
https://self-service.vaillant.co.uk/warranty-registration
Vaillant is a licensed member of the Benchmark Scheme. Benchmark places responsibilities on both manufacturers and installers.
The purpose is to ensure that customers are provided with the correct equipment for their needs, that it is installed, commissioned
and serviced in accordance with the manufacturer’s instructions by a competent person approved at the time by the Health and
Safety Executive and that it meets the requirements of the appropriate Building Regulations.
The Benchmark Checklist can be used to demonstrate compliance with Building Regulations and should be provided to the customer
for future reference.
Installers are required to carry out installation, commissioning and servicing work in accordance with the Benchmark Code of
Practice which is available from the Heating and Hotwater Industry Council who manage and promote the Scheme.
Benchmark is managed and promoted by the Heating and Hotwater Industry Council.

8Installation and maintenance instructions ecoTEC pro 0020244995_04
3 Technical data
Technical data –General
VUW 246/5-
3 (H-GB)
ecoTEC pro
24
VUW 286/5-
3 (H-GB)
ecoTEC pro
28
VUW 286/5-
3 (P-GB)
ecoTEC pro
28
Designated country (des-
ignation in accordance
with ISO 3166)
GB (Great
Britain), IE
(Ireland)
GB (Great
Britain), IE
(Ireland)
GB (Great
Britain), IE
(Ireland)
Approved unit categories II2H3P II2H3P II2H3P
Gas connection, boiler
side
15 mm 15 mm 15 mm
Flow/return heating con-
nections, boiler side
22 mm 22 mm 22 mm
Hot and cold water con-
nection, boiler side
G 3/4″G 3/4″G 3/4″
Expansion relief valve
connection pipe (min.)
15 mm 15 mm 15 mm
Air/flue gas connection 60/100 mm 60/100 mm 60/100 mm
Condensate drain pipe-
work (min.)
19 mm 19 mm 19 mm
G20 natural gas flow
pressure
2.0 kPa
(20.0 mbar)
2.0 kPa
(20.0 mbar)
–
G31 propane gas flow
pressure
––3.7 kPa
(37.0 mbar)
Gas flow rate at 15 °C
and 1013 mbar (based
on domestic hot water
generation, if applicable),
G20
2.5 m³/h 2.9 m³/h –
Gas flow rate at 15 °C
and 1013 mbar (based
on domestic hot water
generation, if applicable),
G31
––2.2 kg/h
Min. flue gas mass flow
rate (G20)
2.47 g/s 2.47 g/s –
Min. flue gas mass flow
rate (G31)
––3.49 g/s
Max. flue gas mass rate 10.8 g/s 12.6 g/s 12.6 g/s
Min. flue gas temperature 40 ℃40 ℃40 ℃
Max. flue gas temperat-
ure
70 ℃70 ℃70 ℃
Approved gas-fired units C13, C33,
C43, C53
C13, C33,
C43, C53
C13, C33,
C43, C53
30% efficiency 109.4 % 109.4 % 108 %
NOx class 666
Test symbol/registration
no.
CE‑
0085CM0320
CE‑
0085CM0320
CE‑
0085CM0320
SAP 2009/2012 annual
efficiency (%)
89.5 % 89.5 % 89.7 %
Boiler dimension, width 440 mm 440 mm 440 mm
Boiler dimension, height 720 mm 720 mm 720 mm
Boiler dimension, depth 338 mm 338 mm 338 mm
Approx. net weight 38 kg 38 kg 38 kg

0020244995_04 ecoTEC pro Installation and maintenance instructions 9
Technical data –G20 power/loading G20
VUW 246/5-
3 (H-GB)
ecoTEC pro
24
VUW 286/5-
3 (H-GB)
ecoTEC pro
28
Nominal heat output
range P at 50/30 °C
5.9 to 24.8 kW 5.9 to 25.9 kW
Nominal heat output
range P at 80/60 °C
5.2 to 23.0 kW 5.2 to 24.0 kW
Maximum heat output
for domestic hot water
generation
23.5 kW 24.5 kW
Maximum heat input for
domestic hot water gen-
eration
23.7 kW 27.5 kW
Maximum heat input,
heating side
23.5 kW 24.5 kW
Minimum heat input 5.5 kW 6.6 kW
Heating adjustment range 5 to 19 kW 5 to 19 kW
Nominal heat input ef-
ficiency (stationary) at
40/30 °C
107.0 % 107.0 %
Nominal heat input ef-
ficiency (stationary) at
50/30 °C
106.0 % 106.0 %
Nominal heat input ef-
ficiency (stationary) at
60/40 °C
101.0 % 101.0 %
Nominal heat input ef-
ficiency (stationary) at
80/60 °C
98.0 % 98.0 %
Technical data –Power/loading G31
VUW 286/5-
3 (P-GB)
ecoTEC pro
28
Nominal heat output
range P at 50/30 °C
7.9 to 25.3 kW
Nominal heat output
range P at 80/60 °C
7.2 to 24.0 kW
Maximum heat output
for domestic hot water
generation
24.5 kW
Maximum heat input for
domestic hot water gen-
eration
27.5 kW
Maximum heat input,
heating side
24.5 kW
Minimum heat input 7.7 kW
Nominal heat input ef-
ficiency (stationary) at
40/30 °C
105.0 %
Nominal heat input ef-
ficiency (stationary) at
50/30 °C
103.0 %
Nominal heat input ef-
ficiency (stationary) at
60/40 °C
101.0 %
Nominal heat input ef-
ficiency (stationary) at
80/60 °C
98.0 %

10 Installation and maintenance instructions ecoTEC pro 0020244995_04
Technical data –Heating
VUW 246/5-
3 (H-GB)
ecoTEC pro
24
VUW 286/5-
3 (H-GB)
ecoTEC pro
28
VUW 286/5-
3 (P-GB)
ecoTEC pro
28
Maximum flow temperat-
ure
85 ℃85 ℃85 ℃
Max. flow temperature
adjustment range (default
setting: 75 °C)
30 to 80 ℃30 to 80 ℃30 to 80 ℃
Permissible total over-
pressure
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
Minimum pressure for
full operation
0.08 MPa
(0.80 bar)
0.08 MPa
(0.80 bar)
0.08 MPa
(0.80 bar)
Expansion vessel capa-
city
10 l 10 l 10 l
Circulation water volume
(with reference to
ΔT= 20 K)
813 l/h 813 l/h 813 l/h
Approx. condensate rate
(pH value 3.5 to 4.0) in
50/30 °C heating mode
1.9 l/h 1.9 l/h 1.9 l/h
Remaining feed head of
pump (at nominal circula-
tion water volume)
0.025 MPa
(0.250 bar)
0.025 MPa
(0.250 bar)
0.025 MPa
(0.250 bar)
Technical data –Hot water handling mode
VUW 246/5-
3 (H-GB)
ecoTEC pro
24
VUW 286/5-
3 (H-GB)
ecoTEC pro
28
VUW 286/5-
3 (P-GB)
ecoTEC pro
28
Lowest water volume 2.0 l/min 2.0 l/min 2.0 l/min
Water volume (at
ΔT = 30 K)
11.2 l/min 13 l/min 13 l/min
Water volume (at
ΔT = 35 K)
9.6 l/min 11.1 l/min 11.1 l/min
Water volume (at
ΔT = 42 K)
8.0 l/min 9.3 l/min 9.3 l/min
Permitted overpressure 1.0 MPa
(10.0 bar)
1.0 MPa
(10.0 bar)
1.0 MPa
(10.0 bar)
Required connection
pressure
0.035 MPa
(0.350 bar)
0.035 MPa
(0.350 bar)
0.035 MPa
(0.350 bar)
Hot water output temper-
ature range
35 to 65 ℃35 to 65 ℃35 to 65 ℃
Technical data –Electrics
VUW 246/5-
3 (H-GB)
ecoTEC pro
24
VUW 286/5-
3 (H-GB)
ecoTEC pro
28
VUW 286/5-
3 (P-GB)
ecoTEC pro
28
Electric connection 230 V/50 Hz 230 V/50 Hz 230 V/50 Hz
Permissible connected
voltage
190 to 253 V 190 to 253 V 190 to 253 V
Built-in fuse (slow-blow) 2 A 2 A 2 A
Min. electrical power con-
sumption
35 W 35 W 35 W
Max. electrical power
consumption
80 W 85 W 85 W
Standby electrical power
consumption
<2W <2W <2W
Level of protection IP X4 D IP X4 D IP X4 D

0020244995_04 ecoTEC pro Installation and maintenance instructions 11
4 Notes on the documentation
▶Always observe all operating instructions enclosed with
the installation components.
▶Store these instructions and all other applicable docu-
ments for further use.
These instructions apply only to:
Product article number
Article num-
ber
Gas Council
Number
VUW 246/5-3 (H-GB)
ecoTEC pro 24
0010021836 47-044-88
VUW 286/5-3 (H-GB)
ecoTEC pro 28
0010021837 47-044-89
VUW 286/5-3 (P-GB)
ecoTEC pro 28
0010021838 47-044-90
5 Product description
5.1 CE marking
The CE marking shows that the products comply with the
basic requirements of the applicable directives as stated on
the declaration of conformity.
The declaration of conformity can be viewed at the manufac-
turer's site.
5.2 Energy Saving Trust Endorsed Products
Only the most energy efficient products can carry the
‘Energy Saving Trust Endorsed Product’ brandmark making
it easy for consumers to choose products that have met strict
energy performance criteria.
Available for: Boilers, Heating controls and chemical inhib-
itors, the Energy Saving Trust endorsed product brandmark
gives consumers confidence that a product will cost less to
run, help lower energy bills and reduce carbon emissions.
About the Energy Saving Trust
Energy Saving Trust is an independent and impartial organ-
isation that provides trusted energy saving advice to em-
power millions of people to lead affordable, low energy life-
styles. For more information visit energysavingtrust.org.uk
5.3 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
5.4 Information on the identification plate
The identification plate is mounted on the underside of the
product in the factory.
Information on the
data plate
Meaning
Read the instructions.
VUW… Vaillant gas-fired wall-hung boiler for
heating and domestic hot water genera-
tion
..6/5-3 Gross calorific value power/product
generation equipment
ecoTEC pro Product designation
2H, G20 –20 mbar
(2.0 kPa)
Gas group and gas connection pressure
as set at the factory
ww/yyyy Date of manufacture: Week/year
Cat. Permissible gas categories
Types Approved gas-fired units
PMS Permissible total overpressure in heating
mode
PMW Permissible total overpressure during
domestic hot water generation
Tmax. Max. flow temperature
ED 92/42 Current efficiency directive fulfilled with
4* rating
V Hz Mains voltage and mains frequency
W Max. electrical power consumption
IP IP rating
Heating mode
Domestic hot water generation
P Nominal heat output range
Q Heat input range
D Nominal domestic hot water draw-off rate
Barcode with serial number,
7th to 16th digit = product article number
Note
Make absolutely sure that the product is compat-
ible with the gas group at the installation site.

12 Installation and maintenance instructions ecoTEC pro 0020244995_04
5.5 Serial number
The serial number can be found on a plastic label at the bot-
tom of the front casing and on the identification plate.
5.6 Product design
5.6.1 Functional elements, product with
integrated domestic hot water generation
6
7
8
9
10
11
13
14
16
4
3
1
2
19
18
17
15
5
12
1 Gas valve assembly
2 Water pressure sensor
3 Heat exchanger
4 Connection for the
air/flue pipe
5 Flue gas analysis point
6 Expansion vessel
7 Air intake pipe
8 Compact thermal
module
9 Ignition electrode
10 Fan
11 Automatic air vent
12 Manometer
13 Internal pump
14 Prioritising diverter
valve
15 Expansion relief valve
16 Electronics box
17 Impeller sensor (do-
mestic hot water)
18 Bypass valve
19 Secondary heat ex-
changer
5.7 Safety Devices
5.7.1 Electrical Supply Failure
The boiler will not work without an electrical supply. Normal
operation of the boiler should resume when the electrical
supply is restored.
Reset any external controls, to resume normal operation of
the central heating.
If the boiler does not resume normal operation press the
reset button. If the boiler does not resume normal operation
after this call your Installation/Servicing company or Vaillant
service.
5.7.2 Overheating Safety
The boiler software is designed to recognise the potential for
an overheat lockout and will shutdown before this happens.
To restart the boiler, press the reset button on the boiler
interface.
If the boiler fails to resume normal operation and all external
controls are calling for heat, then call your Installation/ Servi-
cing company or Vaillant service.
5.7.3 Frost protection
The appliance has a built in frost protection device that pro-
tects the boiler from freezing. With the gas and electric sup-
plies ON and irrespective of any room thermostat setting, the
frost protection device will operate the pump when the tem-
perature of the boiler water falls below 12 °C.
A timer is used so that the temperature can be checked peri-
odically. After 10 minutes the pump will be stopped if the
temperature is higher than 10 °C or has already reached
35 °C. The burner will activate if the boiler temperature does
not reach 10 °C after 30 minutes or at any time if the temper-
ature drops to 5 °C.
The burner will switch off when the temperature reaches
35 °C.
5.7.4 Condensate Drain Blockage
As a safety feature the boiler will stop working if the con-
densate drain becomes blocked. During freezing conditions
this may be due to the forming of ice in the condense drain
external to the house. Release an ice blockage by the use
of warm cloths on the pipe. After pressing reset the boiler
should restart.

0020244995_04 ecoTEC pro Installation and maintenance instructions 13
6 Set-up
6.1 Checking the scope of delivery
▶Check that the scope of delivery is complete and intact.
6.1.1 Scope of delivery
Num-
ber Designation
1Heat generator
1 Installation set containing the following:
1- Unit mounting bracket
1- Expansion relief valve connection pipe
1 - Domestic hot water connection pipe
4 - Service valve
3- Bag with small parts
1Mounting template
1Condensate discharge hose
1 Enclosed documentation
6.2 Dimensions
720
20
624
160
125
188
100 100
3535
440
A
338
180
125
2
1
3
5
7
9
8
4
6
6
47
11 10
3512
1 Air/flue pipe wall duct
2 Unit mounting bracket
3 Heating flow (22 ×1.5
diameter)
4 Domestic hot water
connection (15 ×1.5
diameter)
5 Gas connection
(15 ×1.5 diameter)
6 Cold water connection
(15 ×1.5 diameter)
7 Heating return (22 ×1.5
diameter)
8 R1 tundish/condensate
trap connection
9 Air/flue pipe connection
10 Condensate discharge
connection, 19 mm
diameter
11 Condensate trap
12 Drain pipework connec-
tion, expansion relief
valve, heating, 15 mm
diameter

14 Installation and maintenance instructions ecoTEC pro 0020244995_04
Consult the installation template that is supplied to find the
dimension A.
6.3 Installation site
This boiler is not suitable for outdoor installation. This boiler
may be installed in any room. However if the boiler is being
installed in a room containing a bath or shower it must only
be installed in zones 2 or 3. In GB this is the current I.E.E.
WIRING REGULATIONS and BUILDING REGULATIONS. In
IE reference should be made to the current edition of I.S.813
“Domestic Gas Installations” and the current ETCI rules.
If the boiler is to be installed in a timber frame building it
should be fitted in accordance with the current version of the
Institute of Gas Engineers document IGE/UP/7. If in doubt
seek advice from local gas undertaking or the manufacturer.
6.4 Minimum clearances
B A
C C D
Minimum clearance
A 165 mm: Air/flue pipe, 60/100 mm diameter
275 mm: Air/flue pipe, 80/125 mm diameter
B 180 mm; optimum approx. 250 mm
C 5 mm; optimum approx. 50 mm
D 500 mm in front of the heat generator to enable
easy access for maintenance work (may be
provided by an opening door).
It is not necessary to maintain a clearance between the
product and components made of combustible materials that
go beyond the minimum clearances.
6.5 Compartment Ventilation
The boilers are very high efficiency appliances.
As a consequence the heat loss from the appliance casing
during operation is very low.
Compartment ventilation is not required as the products are
only certified, and can only be fitted with a concentric flue
system.
6.6 Air/flue pipe
6.6.1 Regulation
Different flue outlet configurations can be carried out.
–Consult the installation manual for air/flue gas systems
for more information about the other possibilities and
associated accessories.
Minimum fall
44 mm/m
–Standard flue terminal kits have an in-built fall back to
the boiler to drain the condensate. These can be fitted
level between the appliance and the termination position.
All other extended flues must have a fall of at least 44
mm/m.
The maximum length of the flue outlet is defined according to
its type (for example C13).
–Whatever the kind of flue system chosen, observe the
minimum distances to position the flue terminals.
–To install the flue, refer to the separate flue instruction
supplied with your appliance.
–Explain these requirements to the user of the appliance.
In GB the minimum acceptable siting dimensions for the
terminal from obstructions, other terminals and ventilation
openings are shown in diagram overleaf.
In IE the minimum distances for flue terminal positioning
must be those detailed in I.S. 813 “Domestic Gas Installa-
tions”.
The terminal must be exposed to the external air, allowing
free passage of air across it at all times.
Being a condensing boiler some pluming may occur from
the flue outlet. This should be taken into consideration when
selecting the position for the terminal.

0020244995_04 ecoTEC pro Installation and maintenance instructions 15
6.6.2 Position of the air/flue terminal
J
J
N
Q
S
S
P
UB
Boundary
G
D
J
JR
VM
T
G
C
W
E
F
L
A
K
S
P
S
F
X
A
Y
Boundary
Z
H
Aa
S
Z
Ba
6.6.2.1 Positioning the terminal of a fan-supported flue system
Installation site Dimen-
sions
AAdjacent to a boundary. 300 mm
B1) The dimension below eaves, balconies and car ports can be reduced to this value, as long as the flue terminal is
extended to clear any overhang. External flue joints must be sealed with a suitable silicon sealant. 25 mm
C Between a vertical flue terminal and a window or dormer window on a roof. 1,500 mm
D Between terminals facing each other. 1,200 mm
E Vertical flue clearance, adjacent to a boundary line. 300 mm
F2) Distance to a boundary line, unless it will cause a nuisance. BS 5440:Part 1 recommends that care is taken when
siting terminal in relation to boundary lines. 600 mm
G Minimum clearance from a skylight to a vertical flue or to another vertical flue. Min.
300 mm
HVertical flue clearance, to noncombustible building material.
Vertical flue clearance to combustible building material.
500 mm
1,500 mm
J Above, below and either side of an opening door, air vent or opening window. 300 mm
K Diagonally to an opening door, air vent or opening window. 600 mm
L2) To an internal or external corner. 200 mm
MBelow a Velux window.
Above or to either side of the Velux window.
2,000 mm
600 mm
NFrom a pitched roof.
In regions with heavy snowfall.
400 mm
500 mm
P From vertical drain pipes and soil pipes. 25 mm
1) There should be no ventilation/opening in the eaves within 300 mm distance of the terminal.
2) These dimensions comply with the building regulations, but they may need to be increased to avoid wall staining
and nuisance from pluming depending on site conditions.
–Terminals must be positioned so to avoid combustion products entering the building.
–Support the flue at approximately one metre intervals and at a change of direction, use suitable brackets and
fixings.
–Installations in car ports are not recommended.
–The flue cannot be lower than 1 metre from the top of a lightwell due to the build up of combustion products.
–Dimensions from a flue terminal to a fanned air inlet to be determined by the ventilation equipment.

16 Installation and maintenance instructions ecoTEC pro 0020244995_04
Installation site Dimen-
sions
QBelow eaves.
Below gutters, pipe and drains.
200 mm
75 mm
RThe dimension below eaves, balconies and car ports can be reduced to this value, as long as the flue terminal is
extended to clear any overhang. External flue joints must be sealed with suitable silicon sealant. 25 mm
S Above adjacent ground or balcony. 300 mm
T2) Distance to a surface facing a terminal, unless it will cause a nuisance. BS 5440: Part 1 recommends that care is
taken when siting terminals in relation to surfaces facing a terminal.
600 mm
U Clearance alongside another terminal. 300 mm
V Above roof level. 300 mm
W Minimum to vertical structure on roof, roof vent. Min.
300 mm
X Minimum to opening in adjacent building. Min.
2000 mm
Y Minimum at an angle to a boundary which is not less than 300 mm to the terminal Min.
600 mm
Z Minimum measured to the nearest corner of the OPEN window Min.
600 mm
Aa No more than this value above ridge. Max.
300 mm
Ba Not less than this value below the opening window Min.
300 mm
1) There should be no ventilation/opening in the eaves within 300 mm distance of the terminal.
2) These dimensions comply with the building regulations, but they may need to be increased to avoid wall staining
and nuisance from pluming depending on site conditions.
–Terminals must be positioned so to avoid combustion products entering the building.
–Support the flue at approximately one metre intervals and at a change of direction, use suitable brackets and
fixings.
–Installations in car ports are not recommended.
–The flue cannot be lower than 1 metre from the top of a lightwell due to the build up of combustion products.
–Dimensions from a flue terminal to a fanned air inlet to be determined by the ventilation equipment.
6.6.2.2 Horizontal terminal positioning
BS 5440-1 recommends that fanned flue chimney terminals should be positioned as follows:
a) at least 2 m from an opening in the building directly opposite, and
b) so that the products of combustion are not directed to discharge directly across a boundary if the products are likely to
cause a nuisance to a neighbour or discharge over a walkway or patio.
For IE see current issue of IS 813.
For boilers covered within this manual.
Dimensions B and R:
These clearances may be reduced to 25 mm without affecting the performance of the boiler. In order to ensure that the con-
densate plume does not affect adjacent surfaces the terminal should be extended as shown below.
Balcony/eaves
Gutter
Adequately secured
air/flue gas pipe
The flue pipe must
protrude beyond any overhang
You can use a plume management kit to enable the termination point to be positioned and directed away from the building
fabric.

0020244995_04 ecoTEC pro Installation and maintenance instructions 17
6.6.3 Flue Configuration Description
6.6.3.1 Horizontal Concentric Flue ⌀60/100 mm or
⌀80/125 mm (C13 type installation)
1
1 Gasket (fitted)
Note
If the terminal is at less than 1.80 m from the
ground, you must install a terminal protection kit.
Consult the separate installation manual for air/flue gas sys-
tems supplied with your appliance for all possibilities and as-
sociated accessories and how to install the flue system.
6.6.3.2 Terminal protection
A terminal guard is required if persons could come into con-
tact with the terminal or the terminal could be subject to dam-
age.
If a terminal guard is required, it must be positioned to
provide minimum of 50 mm clearance from any part of the
terminal and be central over the terminal.
The guard should be similar to that shown in the figure.
6.6.3.3 Vertical Concentric Flue ⌀60/100 mm or
⌀80/125 mm (C33 type installation)
Consult the separate installation manual for air/flue gas sys-
tems supplied with your appliance for all possibilities and as-
sociated accessories and how to install the flue system.
6.6.3.4 Multiple boiler chimney Flue ⌀60/100 mm
(C43 type installation)
A
B
L
4
5
1
2
3
1 Pressure balancing
system
2 Air-inlet pipe
3 Collector pipe

18 Installation and maintenance instructions ecoTEC pro 0020244995_04
4 Boiler
5 Inspection hatch
A Final storey
B Ground floor
Note
The flue connecting from the appliance to the flue
system must be supplied from the manufacturer of
the boiler.
C43 flue systems must not be a 'pressurised sys-
tem' but act under natural draught principles.
C43 type flue systems must have their own con-
densate drain fitted and not allow condensate to
mix into other appliances.
The flue length must be calculated and installed according to
the relevant standards EN 13384-1 and 2 (C43 flue systems
only) with reference to the manufacturer's instructions sup-
plied. The appliance maximum flue length must be taken into
account when calculating the overall design of the flue sys-
tem.
Consult the separate installation manual for air/flue gas sys-
tems supplied with your appliance for all possibilities and as-
sociated accessories and how to install the flue system.
6.7 Using the installation template
▶Use the installation template to ascertain the locations at
which you need to drill holes and make breakthroughs.
6.8 Wall-mounting the product
1. Check the load-bearing capacity of the wall.
2. Note the total weight of the product.
3. Only use fixing material that is permitted for the wall.
4. If required, ensure that mounting apparatus on-site has
sufficient load-bearing capacity.
5. Wall-mount the product as described.
1
6. Install the product bracket (1) on the wall.
7. Hang the product on the product bracket from above
using the hanging bracket.
6.9 Removing/installing the front casing
6.9.1 Removing the front casing
▶Remove the front casing as shown in the illustration.
6.9.2 Installing the front casing
▶Refit the components in the reverse order.

0020244995_04 ecoTEC pro Installation and maintenance instructions 19
6.10 Removing/installing the side section
6.10.1 Removing the side section
2x
B
A
C
D
Caution.
Risk of material damage caused by mech-
anical deformation.
Removing both side sections may cause
mechanical distortion in the product, which
may cause damage to the piping, for ex-
ample, and potentially result in leaks.
▶Always only remove one side section –
never both side sections at the same time.
▶Remove the side section as shown in the illustration.
6.10.2 Installing the side section
▶Refit the components in the reverse order.

20 Installation and maintenance instructions ecoTEC pro 0020244995_04
7 Installation
7.1 Installation requirements
7.1.1 Information on the gas group
In the as-supplied condition, the product is preset for opera-
tion with the gas group indicated on the data plate.
7.1.2 Purging the liquid gas tank
If the liquid gas tank is not purged properly, this may result in
ignition problems.
▶Ensure that the liquid gas tank has been purged properly
before installing the product.
▶If required, contact the filler or the liquid gas supplier.
7.1.3 Using the correct gas type
Using the incorrect gas type may cause fault shutdowns in
the product. Ignition and combustion noise may occur in the
product.
▶Only use the gas type listed on the data plate.
7.1.4 Preparing for installation
1. Make sure that the existing gas meter is capable of
passing the rate of gas supply required.
2. Consider the maximum heat output given in DHW
mode.
3. Install a system separator (to be provided on-site) dir-
ectly on the cold water connection for the combi boiler.
4. Install the following components:
–Draining cocks at the lowest points in the heating
installation (→current version of "BS 2879")
–A stopcock on the cold water connection
–A stopcock in the gas pipe
5. Check that the volumetric capacity of the expansion
vessel is sufficient for the system volume.
Condition: The volume of the installed expansion vessel is insufficient
▶Install an additional expansion vessel, connected as
close to the product as possible, in the heating return.
Condition: External expansion vessel installed and warm start active
▶Install a non-return valve in the product outlet (heating
flow) or decommission the internal expansion vessel
in order to prevent the warm start function from being
increasingly activated due to backflow.
6. Install the connection pipes such that they are free from
mechanical stress.
7. If you use non-diffusion-tight plastic pipes in the heating
installation, ensure that no air gets into the heat gener-
ator circuit.
8. Only solder connectors if the connectors are not yet
screwed to the service valves.
9. Only bend connection pipes if they have not yet been
connected to the product.
10. Flush the heating installation thoroughly before
installing the product.
11. Check the leak-tightness of the gas valve assembly
using a pressure of ≤11 kPa (110 mbar).
7.1.5 Descaling the water
Scale deposition increases as the water temperature in-
creases.
▶Descale the water as required.
7.2 Installing the gas connection
1. Install the gas pipe in accordance with the recognised
rules of technology.
2. Connect the product to the gas line as shown in ac-
cordance with the recognised rules of good engineer-
ing practice.
3. Remove the residues from the gas line by blowing
through the gas line beforehand.
4. Purge the gas line before start-up.
7.3 Checking the gas line for leak-tightness
▶Check the entire gas line properly for leak-tightness.
7.4 Installing the hot and cold water connection
1. Make the water connections as shown in accordance
with the relevant standards.