Wolf FGB-K Series Instruction Manual

GB
IE
Wolf GmbH / Postfach 1380 / D-84048 Mainburg / Tel. [phone] / Fax [phone] / www.wolf.eu
Document no.: 3064458_201811 Subjecttotechnicalmodications
Installation and maintenance instructions for contractors
Wall mounted gas
condensing boiler
FGB wall mounted gas condensing boiler
FGB-K wall mounted gas condensing combi boiler
FGB-28
FGB-35
FGB-K-28
FGB-K-35
from FW 1.20

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Table of contents
1. Information on documentation / standard delivery ...........................3
2. Safety instructions............................................................................5
3. Dimensions ......................................................................................8
4. Specification.....................................................................................9
5. Set-up.............................................................................................10
6. Standards and regulations .............................................................12
Installation
7. Positioning......................................................................................15
8. Installation dimensions...................................................................16
9. Opening the casing ........................................................................17
10. Installation ......................................................................................18
11. Gas connection ..............................................................................19
12. Fitting the trap ................................................................................20
13. Air/flue gas routing .........................................................................21
Control unit
14. Electrical connection ......................................................................22
15. Control unit.....................................................................................28
16. HG control parameters...................................................................33
17. Parameter description ....................................................................35
Commissioning
18. Filling the heating system / trap .....................................................44
19. Filling for optional appliance versions ............................................50
20. Draining the heating system...........................................................51
21. Determining the gas type ...............................................................52
22. Checking the gas supply pressure ................................................. 53
24. Adjusting the maximum heating output .......................................... 56
25. Checking the combustion parameters............................................57
26. High efficiency pump function description......................................58
27. Commissioning report ....................................................................60
Maintenance
28.1. Maintenance – Fault messages .....................................................62
28.2. Maintenance – Spare parts maintenance set.................................63
28.3. Preparing for maintenance ............................................................64
28.4. Determining the soiling level on the heating water heat exchanger
(flue gas side)..........................................................................................65
28.5. Burner maintenance.......................................................................66
28.6. Checking the ignition ionisation electrode......................................68
28.7. Cleaning the trap / checking the expansion vessel ........................ 69
28.8. Removing the heat exchanger .......................................................70
28.9. Assembling the heat exchanger.....................................................72
29. Checking the DHW heating............................................................75
Specication
30. Safety devices................................................................................76
32. Design information, underfloor heating / DHW circulation .............93
33. Service report.................................................................................94
34. Troubleshooting..............................................................................95
35. FGB wiring diagram .......................................................................99
36. Product fiche according to Regulation (EU) no. 811/2013 ...........100
37. Technical parameters according to EU regulation no. 813/2013.. 102
EU DECLARATION OF CONFORMITY................................................103

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1. Information on documentation /
standard delivery
Operating instructions for users
Also applicable are the instructions for all accessory modules and any further acces-
sories used.
The system user or operator should ensure the safekeeping of all instruction manuals
and documents.
Pass on these installation instructions as well as all other applicable manuals to the
system user or operator.
- Instruct the system user to take out an inspection and maintenance contract with an
approved contractor.
- Inform the system use that the annual inspection and maintenance may only be per-
formed by an approved contractor.
- Inform the system use that repair work may only be performed by an approved con-
tractor.
- Inform the system user that only original spare parts may be used.
- Inform the system user that no technical changes may be made to the boiler or control
unit.
- Inform the system user that they are responsible for the safety, environmental compat-
ibility and energy quality of the heating system (German Immission Control Act/Energy
Saving Ordinance) [Germany].
- Inform the system user that these instructions and the other applicable documents
must be kept in a safe place
These installation instructions apply to the FGB-(K) gas condensing boilers.
- Old equipment may only be disconnected from the gas and electricity supply by a
qualied contractor.
- Always dispose of materials according to environmental, recycling and waste manage-
ment standards.
- Old equipment, worn parts, defective components and liquids and oils which are a
hazard to the environment must be disposed of or recycled according to the applicable
waste disposal regulations in an environmentally compatible manner.
They must not be disposed of as household waste.
- Dispose of packaging made of cardboard, recyclable plastics and synthetic ller mate-
rials in an environmentally compatible manner through appropriate recycling systems
or a recycling centre.
- Please observe the applicable national and local regulations
Other applicable documents
Safekeeping of these documents
Instructing the system user
Applicability of these instructions
Recycling and disposal

43064458_201811
1 x gas condensing boiler, ready to connect, with casing
1 x suspension bracket for wall mounting
1 x installation and maintenance instructions for contractors
1 x operating instructions for users
1 x commissioning checklist
1 x
power cable with standard plug, exible, 3 x 0.75 mm²
1 x M16 cable gland
3 x M12 cable glands
5 x cable ties
1 x trap
1 x 1000 mm condensate hose
1 x bleed key
The following accessories are required for installing the gas condensing boiler:
- Air / ue gas accessories (see design information)
- Condensate drain outlet with hose retainer
- Maintenance shut-off valves for heating ow and return
- Gas ball valve with re protection
- Safety assembly for DHW
- Cylinder connections short circuiting pipework (for heating operation only)
Other accessories as per pricelist.
Standard delivery
Accessories
1. Information on documentation /
standard delivery

3064458_201811 5
2. Safety instructions
Authorised personnel should read these instructions
before any installation, commissioning or maintenance
work. Observe the instructions given in this document.
Failure to observe these installation instructions voids
any WOLF warranty.
In some countries, the installation of a gas boiler must
benotiedtoandapprovedbytherelevantgassupply
company.
Please note that regional permits may be required for
theuesystemandforconnectingthecondensate
drain to the public sewer.
Beforeinstallationworkbegins,thelocaluegas
inspector and water authority must be informed.
The gas condensing boiler must be installed,
commissionedand maintained byqualied andtrained
personnel only. In accordance with VDE 0105 Part 1,
work on electrical components (e.g. control units) must
onlybecarriedoutbyqualiedelectricians.
Electrical installation work is governed by VDE/ÖVE
regulations and those of your local power supply utility.
Only operate the gas condensing boiler within its output
range, which is stated in the technical documentation
supplied by WOLF. Intended use of the boiler includes
the exclusive use for hot water heating systems in ac-
cordance with DIN EN 12828.
The gas condensing boiler is intended solely for instal-
lation and operation in sealed unvented heating sys-
tems.
Never remove, bypass or otherwise disable any safety
or monitoring equipment. Only operate the boiler when
it is in perfect technical condition.
Any faults or damage which impact or might impact
upon safety must be remedied immediately by a
qualiedcontractor.Onlyreplacefaultycomponentsand
equipment with original WOLF spare parts.
Danger: if you smell gas
- Close the gas tap.
- Open the windows.
- Do not operate any electrical switches.
- Extinguish naked flames.
- Phone the gas supply utility company and an ap-
proved contractor from an external location.
Danger:ifyousmelluegas
- Switch OFF the appliance.
- Open windows and doors.
- Notify an approved contractor.
Danger from "live" electrical components
Never touch electrical components or contacts
when the ON/OFF switch is in the ON position.
There is a danger of electrocution, resulting in
a risk to health or death. The main terminals are
'live', even when the ON/OFF switch is in the OFF
position.
The main terminals are ‘live’, even when the ap-
pliance is set to “OFF”.
Risk of scalding
Boilers may contain hot water.
Hot water can cause severe scalding.
Before working on parts which are in contact
with water, allow the appliance to cool to below
40 °C, shut off all valves and, if necessary, drain
the appliance.
Risk of burns
Boiler components may be extremely hot.
Hot components can cause burns.
Before working on the opened up appliance, al-
low it to cool below 40 °C or wear suitable gloves.
The boiler is intended solely for installation and
operation in sealed unvented heating systems.
Symbols
The following warning symbols are used in these instruc-
tions.
These relate to personal safety and operational reliability.
Instructions that must be followed precisely in order
to prevent risk and injury to persons.
Instructions that must be followed precisely in order
to prevent risk and injury to persons from live electri-
cal components.
Indicates technical instructions that must be
observed to prevent damage to the boiler and
malfunctions.
Please note

63064458_201811
Danger from pressurised water
Boilers are subject to high water pressure.
Water pressure can cause severe injuries.
Before working on parts which are in contact
with water, allow the appliance to cool to below
40 °C, shut off all valves and, if necessary, drain
the appliance.
Note:
Sensors can be in contact with water and there-
fore exposed to pressure.
Working on the system
- Close the gas shut-off valve and secure it against uninten-
tional reopening.
- Isolate the system from the power supply (e.g. by remov-
ing the separate mains fuse or by means of a main switch
or a heating emergency stop switch) and check to ensure
there is no voltage.
- Safeguard the system against reconnection.
Inspection and service
- Ensure the correct operation of the gas boiler by having a
contractor carry out inspections at least once a year and
maintenance/repair when required.
- (DVGW - TRGI 2008 - G600).
We recommend arranging a suitable maintenance con-
tract.
- The operator is responsible for the safety, environmental
compatibility and energy quality of the heating system
(German Immission Control Act/Energy Saving Ordi-
nance) [Germany].
- Only use genuine WOLF spare parts.
2. Safety instructions

3064458_201811 7
2. Safety instructions
Fig: Ignition transformer, high voltage ignition electrode, combustion
chamber, 3-way diverter valve, pump and fan
Danger through 'live' electrical components, danger from ignition
voltage, danger of burns from hot components.
Fig: Gas combination valve
Risk of poisoning or explosion in the event of gas escaping.
Fig: Gas connection: Risk of poisoning or explosion in the event of
gas escaping.
Fig: Terminal box: Danger through 'live' electrical components.

83064458_201811
Cold water
connection
G 1/2
DHW connection
G 1/2
Heating ow
G 3/4
Heating return
G 3/4
38 at 28 kW 83 at 35 kW
3. Dimensions

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Type FGB-28 FGB-35 FGB-K-28 FGB-K-35
Rated heating output at 80/60 °C kW 24.4/27.3 1) 31.1/34 1) 24.4/27.3 1) 31.1/34 1)
Rated heating output at 50/30 °C kW 27.3 34.9 27.3 34.9
Rated heat input kW 25/28 1) 32/35 1) 25/28 1) 32/35 1)
Lowest heating output (modul.) at 80/60 °C kW 4.8 6.7 4.8 6.7
Lowest heating output (modul.) at 50/30 °C kW 5.3 7.5 5.3 7.5
Lowest heat input (modul.) kW 4.9 6.9 4.9 6.9
Heating ow connection G 3/4"(DN 20) 3/4"(DN 20)
Heating return connection G 3/4"(DN 20) 3/4"(DN 20)
DHW connection / DHW circulation G 1/2“ 1/2“
Cold water connection G 1/2“ 1/2“
Gas connection R 1/2“ 1/2“
Balanced ue connection mm 60/100 60/100
Dimensions Depth mm 310 310
Width mm 408 408
Height mm 720 (incl. device connection ange)
Balanced ue system Type B23P, B33P, C13(x), C33(x), C43(x), C53(x),
C63(x), C83(x), C93(x)
Gas category see table an page 44
Gas supply details
Natural gas E/H (Hi [net cv]=9.5 kWh/m³=34.2 MJ/m³) m³/h 2.63/2.94 3.36/3.68 2.63/2.94 3.36/3.68
Natural gas LL (Hi [net cv]=8.6 kWh/m³=31.0 MJ/m³) m³/h 2.90/3.25 3.72/4.06 2.90/3.25 3.72/4.06
LPG (Hi [net cv]=12.8 kWh/m³=46.1 MJ/m³) kg/h 1.95/2.18 2.5/2.73 1.95/2.18 2.5/2.73
Natural gas supply pressure (permissible min./max.) mbar see table on page 44 see table on page 44
LPG supply pressure (permissible min./max.) mbar see table on page 44 see table on page 44
Efciency at rated load at 80/60 °C (Hi[net cv]/Hs[gross cv]) % 98/88 98/88 98/88 98/88
Efciency at 30 % partial load and TR=30 °C (Hi[net cv]/Hs[gross cv]) % 109/98 109/98 109/98 109/98
Flow temperature. factory setting °C 75 75
Flow temperature up to approx. °C 85 85
Max. overall positive pressure. heating circuit bar 2.5 2.5
Max. residual head for heating circuit: High efciency pump (EEI<0.20)
1075 l/h pump rate (25 kW at dt=20 K) mbar 450 450 450 450
1376 l/h pump rate (32 kW at dt=20 K) mbar - 350 - 350
Max. permiss. overall positive pressure bar 10 10
DHW throughput l/min 2.0-14.4 2.0-14.4
Minimum ow pressure 15502-2-2 bar 0.2 0.3
DHW temperature range (adjustable) °C 30-65 30-65
Spec. water throughput "D" at ΔT = 30 K l/min 13.4 16.3
Expansion vessel. total capacity l 8 8 8 8
Expansion vessel. pre-charge pressure bar 0.75-0.95 0.75-0.95 0.75-0.95 0.75-0.95
Flue gas temperature 80/60-50/30 at Qmax °C 85-65 70-50 85-65 70-50
Flue gas temperature 80/60-50/30 at Qmin °C 50-40 50-40 50-40 50-40
Flue gas mass ow rate at Qmax g/s 11.2/12.50 14.26/15.50 11.2/12.50 14.26/15.50
Flue gas mass ow rate at Qmin g/s 2.33 3.25 2.33 3.25
Available gas fan draught at Qmax Pa 150 160 150 160
Available gas fan draught at Qmin Pa 8 12 8 12
Flue gas category G52 G52
NOx class 6 6
Amount of condensate at 50/30 °C l/h ca. 1.0 ca. 1.7 ca. 1.0 ca. 1.7
pH value of condensate ca. 4.3 ca. 4.3 ca. 4.3 ca. 4.3
Power consumption in standby W 2 2 2 2
Power consumption W max. 102 max. 114 max. 102 max. 114
IP rating IP IPX4D IPX4D IPX4D IPX4D
Power supply/fuse/MCB protection 230V / 50Hz / 3.15A 230V / 50Hz / 3.15A
Total weight (wall mounted gas condensing boiler) kg 27 28 27 28
CE ID number CE-0085CQ0261 CE-0085CQ0261
1) Heating mode / DHW mode
4. Specication

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1 Flue pipe
2 Burner
3 Boiler water temperature sensor
4 Heating water heat exchanger
5 Gas fan
6 Mixing valve (venturi insert)
7 Gas valve
8 Inlet pipe
9 Trap
10 Control unit casing
11 Air vent valve
12 Combustion chamber - high limit safety cut-out
13 Expansion vessel
14 Pressure sensor
15 Return temperature sensor
16 Flue gas temperature sensor
17 3-way valve (motor)
18 Heating circuit pump with air vent valve
19 Heating ow
20 Cylinder ow
21 Gas supply pipe
22 Cylinder return
23 Heating return
FGB wall mounted gas condensing boiler
1
8
9
10
11
12
13
14
15
16
17
18
19 20 21 22 23
2
3
4
6
5
7
5. Set-up

3064458_201811 11
1 Flue pipe
2 Burner
3 Boiler water temperature sensor
4 Heating water heat exchanger
5 Gas fan
6 Mixing valve (venturi insert)
7 Gas valve
8 Inlet pipe
9 Trap
10 Control unit casing
11 DHW outlet temperature sensor
12 Plate heat exchanger
13 Air vent valve
14 Combustion chamber - high limit safety cut-out
15 Expansion vessel
16 Pressure sensor
17 Return temperature sensor
18 Flue gas temperature sensor
19 3-way valve (motor)
20 Heating circuit pump with air vent valve
21 Flow limiter
22 Flow sensor
23 Heating ow
24 DHW connection
25 Gas supply pipe
26 Cold water connection
27 Heating return
1
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23 24 25 26 27
2
3
4
6
5
7
FGB-K wall mounted gas condensing combi boiler
5. Set-up

12 3064458_201811
Observe all standards and guidelines applicable to the installation and
operation of this heating system in your country.
Observe the information on the boiler type plate.
The following local regulations must be complied with during installation and
operation of the heating system:
• Siting conditions
• Ventilation and exhaust air facilities and connection to a chimney
• Electrical connection to the power supply
• Technical regulations of the gas supply utility company regarding the connection of
the gas appliance to the local gas mains
• Regulations and standards regarding the safety equipment of the water heating
system
• DHW installation
6. Standards and regulations
The following general regulations, rules and guidelines must be observed for
installation in particular:
• (DIN) EN 806 Specications for installations inside buildings conveying water for
human consumption
• (DIN) EN 1717 Protection against pollution of potable water installations
• (DIN) EN 12831 Heating systems in buildings – Method for calculating the design
heat load
• (DIN) EN 12828 Heating systems in buildings – Design of water-based heating
systems
• (DIN) EN 13384 Chimneys – Thermal and uid dynamic calculation methods
• (DIN) EN 50156-1 (VDE 0116 Part 1) Electrical equipment for furnaces and
ancillary equipment
• VDE 0470/(DIN) EN 60529 Degrees of protection provided by enclosures
• VDI 2035 Prevention of damage in water heating installations
- Scale formation (Sheet 1)
- Water-side corrosion (Sheet 2)
- Corrosion by fuel gases (Sheet 3)

3064458_201811 13
6. Standards and regulations
The following also apply to installation and operation in Germany:
• Technical Regulations for Gas Installations DVGW-TRGI 1986/1996
(DVGW Code of Practice G600 and TRF)
• DIN 1988 Drinking water supply systems
• DIN 18160 Chimneys
• DWA-A 251 Condensate from condensing boilers
• ATV-DVWK-M115-3 Indirect discharge of non-domestic waste water – Part 3:
Indirect discharge monitoring in practice
• VDE 0100 Erection of power installations with rated voltages below 1000 V
• VDE 0105 Operation of high voltage systems, general stipulations
• KÜO German Federal Sweeping and Inspection Act
• Energy Savings Act (EnEG) and related ordinances:
EnEV Energy Saving Ordinance (currently applicable version)
• DVGW Code of Practice G637
The following apply to installation and operation in Austria in particular:
• ÖVE regulations
• Provisions of the ÖVGW and the corresponding Austrian standards
• ÖVGV TR-Gas (G1), ÖVGW-TRF (G2)
• Provisions of ÖVGW guideline G41 for condensate drainage
• Local regulations of building and industry regulatory agencies (usually represented
by the ue gas inspector [Germany])
• Local regulations of the gas supply utility
• Regulations and requirements of the local power supply utility
• Provisions of regionally applicable building regulations
• The minimum heating water requirements in accordance with ÖNORM H5195-1
must be observed
The following apply to installation and operation in Switzerland in particular:
• SVGW regulations
• VKF regulations
• BUWAL and local regulations must be observed.
• G1 gas guidelines
• EKAS form 1942; LPG guideline Part 2

14 3064458_201811
FGB ... wall mounted gas condensing boiler
Gas condensing boiler, with electronic ignition and electronic
ue gas temperature monitoring, for low temperature heating
and DHW heating in heating systems with ow temperatures
up to 90 °C and 2.5 bar permissible operating pressure to
DIN EN 12828. This Wolf gas condensing boiler is also
approved for installation in garages.
6. Standards and regulations
Gas condensing boilers operated with an open
uemayonlybeinstalledinroomsthatcomply
with the appropriate ventilation requirements.
Otherwise there is a risk of asphyxiation
or poisoning. Read the installation and
maintenance instructions before installing
the boiler. Also take into consideration all
technical information.
When operating the boiler with LPG use only
propane according to DIN 51 622, otherwise
faults may arise when starting and operating
the gas condensing boiler, which may lead to
injury and material losses.
A poorly vented LPG tank can lead to problems
with ignition. In such a case, contact the
companythatllstheLPGtank.
The adjustable cylinder water temperature
can exceed 60 °C. Short-term operation at
temperatures above 60 °C must be monitored
in order to prevent scalding. For permanent
operation, appropriate precautions should be
taken to prevent draw-off temperatures above
60 °C, e.g. thermostatic valve.
To protect against scaling, the DHW temperature should
be set to max. 50 °C when the total water hardness is
15 °dH (2.5 mol/m³) or above.
In accordance with the Drinking Water Ordinance
[Germany], this is the lowest permissible value for
DHW temperatures, as it practically rules out the risk
of legionella proliferation with daily use of the hot
water system. (When installing a DHW cylinder ≤ 400
l; complete exchange of water in the cylinder through
usage within 3 days.)
With a total hardness of 20 °dH or higher, the use of a
water treatment facility in the cold water supply line
when heating DHW is essential, in order to extend the
maintenance intervals.
Even if water hardness is below 20 °dH, a higher risk of
scale build-up may occur locally, necessitating suitable
softening measures. Failure to take such measures will
result in premature scaling of the appliance and reduced
DHW convenience. The contractor should always check
the local conditions.
Fig: Wolf wall-mounted gas condensing boiler

3064458_201811 15
First determine where the appliance is to be installed.
For this, consider the ue outlet, the lateral clearances
towards walls and ceiling and any existing connections for
gas, central heating, DHW and electrics.
Minimum clearances
We recommend observing minimum clearances to facilitate
inspection and maintenance work on the boiler. This ensures
that adequate inspection and function tests can be carried
out on the appliance.
The boiler may only be installed in rooms that
are protected from frost.
The temperature in the installation room must be between
0°C and 40°C.
In addition, all components of the condensing boiler must
be freely accessible from the front. It must be possible to
carry out ue gas emissions tests. If minimum clearances
and accessibility are not observed, Wolf may stipulate
accessibility for on-site customer service attendance.
Operation in wet rooms
In the delivered condition and for balanced ue operation,
the Wolf gas condensing boiler has IP rating IPx4D.
When installing it in wet rooms, the following conditions must
be met:
- Balanced ue operation
- Compliance with IP rating IPX4D
- All outgoing and incoming cables must be routed through
the strain relief cable glands and secured. Tighten the
cable glands securely, to ensure that no water can enter
the casing.
Sound insulation: Under certain critical installation conditions
(e.g. installation on a drywall), additional measures may
be necessary to soundproof the boiler. In such a case, use
anti-vibration rawl plugs and, if necessary, rubber mounts or
insulation strips.
The installation room and the combustion air
supplied to the appliance must be free from
chemicals,e.g.uorideandchlorineorsulphur.
Such materials are contained in sprays, paints,
adhesives, solvents and cleaning agents.
Under unfavourable conditions, these may
leadtocorrosion,includingintheuesystem.
Clearance between the boiler and combustible
materials or components is not required, as
temperatures are limited to 85 °C at the rated
boiler heating output. However, explosive or
readilyammablematerialsmustnotbeused
in the installation room as this would cause a
riskofreorexplosion.
During boiler installation, ensure that no
contaminants (e.g. drilling dust) enter the gas
boiler, as this could lead to appliance faults.
Please note
Fig: Minimum clearances
Lateral clearances min. 40 mm
min. 552 mm
min. 500 mm
7. Positioning
The appliance is not suitable for outdoor
installation.
The boiler is intended solely for installation
and operation in sealed unvented heating
systems.

16 3064458_201811
Flue system component
60/100
Flue system component
80/125
min. 552 mm
Securing the appliance, suspension bracket /
uegassystem
When installing the appliance, ensure that the
xings have sufcient load-bearing capacity. Also
take into account the condition of the wall, to
prevent gas or water from escaping, resulting in a
risk of explosion and ooding.
1.Mark the Ø12 holes to be drilled for the suspension bracket,
taking into account the minimum clearances.
2. Insert the rawl plugs and t the suspension bracket using
the screws supplied.
3.Hook the boiler onto the suspension bracket using the
mounting stay.
8. Installation dimensions
min. 552 mm
146
230

3064458_201811 17
Screw
• Undo the central screw at the bottom of the front casing.
• Push in the two locking hooks at the bottom left and right
and pull the casing forwards.
• Lift the front casing upwards to release it and remove it.
9. Opening the casing

18 3064458_201811
Heating circuit
We recommend installing a maintenance valve in both the heating ow and heating return – straight design for surface mounting.
The return line to the appliance must have a dirt trap. A sludge separator with magnetite separator should be
usedtoprotecttheapplianceandthehighefciencypumpfromdirt/sludgeandmagnetite.
Deposits in the heat exchanger may lead to boiling noise, a drop in performance or faults in the appliance.
Please note
Fig: Drinking water installation
Cold water and DHW connection
A maintenance valve must be installed in the cold water
supply line.
If the cold water supply pressure is above the maximum
permissible operating pressure of 10 bar, install a tested and
certied pressure reducer.
If mixer taps are used, provide a centralised pressure reducer.
Observe the regulations of EN 806 as well as those of your
local water supply utility when connecting cold water and
DHW.Your warranty is void if the installation does not comply
with the illustration shown.
Note: When selecting the installation material for the
system, observe engineering standards and take
into account possible electrochemical processes
(mixed installation).
When installing make sure that, according to
EN 1717, a non return valve is installed in the
drinking water pipeline.
In wall mounted boilers without DHW heating,
install a short circuiting section (accessories)
betweencylinderowandcylinderreturn.
Fig: Cylinder ow / return connections
Cylinder return
G½"
Cylinder ow
G½"
Safety valve Drain outlet Shut-off valve Pressure reducing valve Shut-off valve Cold water supply Drinking water lter Pressure gauge connection Drain outlet Non return valve
10. Installation

3064458_201811 19
Fig: Gas ball valve, straight (accessories)
Fig: Gas ball valve, angled (accessories)
Fig: Gas connection installation
Seite 16
Gaskugelhahn, Durchgangsform
Gaskugelhahn, Eckform
Connect the gas supply line at the gas connection or the
expansion joint (recommended) using gas connection
R½" and an approved sealant. Ensure the supply line is
stress-free.
Only a licensed gas tter may route the gas pipe
and make the gas connections.
Remove all residues from the heating pipework
and the gas line prior to connecting the
condensing boiler, particularly in older systems.
Prior to commissioning, test all pipe and gas
connections for leaks. Inappropriate installation
or using unsuitable components or assemblies
may lead to gas escaping, which results in a risk
of poisoning and explosion.
Install a gas ball valve with re protection in the
gas supply line upstream of the condensing
boiler. This prevents a risk of explosion during a
re. Size the gas supply line in accordance with
DVGW-TRGI regulations.
Mount the gas ball valve in an easily
accessible place.
Carry out a tightness test on the gas line
without the gas condensing boiler. Never
release the test pressure via the gas valve.
Gas ttings on the appliance should be
pressure tested to a maximum of 150 mbar.
Higher pressure may damage the gas valve,
resulting in a risk of explosion, asphyxiation
or poisoning. When pressure testing the
gas line, close the gas ball valve on the gas
condensing boiler.
When installing the gas connection, ensure
all ttings are sufciently tightened to
prevent gas leaks.
11. Gas connection

20 3064458_201811
Before commissioning, carry out a tightness
test on all hydraulic pipework:
Test pressure on the DHW water side max.
10 bar
Test pressure on the heating water side max.
4.5 bar
Fig: Trap
Note:
The condensate hose attached to the trap must not form a
loop or roll up, as this could lead to impaired operation.
12. Fitting the trap
Condensate drain connection
The trap must be tted before commissioning the appliance.
The trap included in the standard delivery must be tted
from underneath the appliance. Before installing, apply
silicone grease to the sealing collar. After insertion, secure
the screw tting of the trap to the connector and check the
connection is rm. Secure the sealing collar.
Ensure that the sealing collar seals the casing base.
The drain hose must be safely secured above the tundish
(trap).
If the condensate is directly routed to the sewer pipe, provide
a ventilation facility. This is to prevent retroactive effects from
the sewer pipe to the gas condensing boiler.
If installing a neutralising system (accessories), observe the
instructions supplied.
According to Code of Practice ATV-DVWK- A251, no
neutralising system is required for condensing boilers up to
200 kW.
If a neutralising system is used, the national regulations
regarding the disposal of residues from such systems apply.
The trap is lled via the ue; see chapter 18 "Filling the
heating system / trap".
Please note
Sealing collar
Tundish for drain hose
Condensate pan connector
Thetrapmustbelledwithwaterpriorto
commissioning. Operating the appliance with
an empty trap presents a risk of poisoning
orasphyxiationduetouegasesescaping.
Unscrewthetrap,removeandlluntilwater
runsoutofthedrainholeontheside.Ret
the trap and ensure the gasket seals tightly.