Viessmann Vitodens 100-W WB1B Series Quick guide

Installation and Service
Instructions
VITODENS
d
100-W
5600 332 v1.3 08/2012
for use by heating contractor
Vitodens 100-W
WB1B Series
Wall-Mounted, gas-fired condensing boiler
with optional on demand hot water CombiPLUS Kit
Read and save these instructions
for future reference.
IMPORTANT
Please file in Service Binder
Heating input 37 to 118 MBH
10.8 to 34.5 kW
Vitodens 100-W, WB1B (with pre-installed coaxial vent pipe adaptor)
and with CombiPLUS Kit installed.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Safety, Installation and Warranty Requirements
Safety
Please ensure that these instructions are read and understood before commencing installation. Failure to comply with
the instructions listed below and details printed in this manual can cause product/property damage, severe personal
injury, and/or loss of life. Ensure all requirements below are understood and fulfilled (including detailed information
found in manual subsections).
WARNING
Installers must follow local regulations with respect
to installation of carbon monoxide detectors. Follow
manufacturer’s maintenance schedule of the boiler.
Product documentation
Read all applicable documentation before commencing
installation. Store documentation near boiler in a
readily accessible location for reference in the future
by service personnel.
uFor a listing of applicable literature,
please see section entitled “Important
Regulatory and Safety Requirements”.
Warranty
Information contained in this and
related product documentation must
be read and followed. Failure to do
so renders the warranty null and void.
Licensed professional heating contractor
The installation, adjustment, service and maintenance
of this equipment must be performed by a licensed
professional heating contractor.
uPlease see section entitled
“Important Regulatory and Installation
Requirements”.
Contaminated air
Air contaminated by chemicals can cause by-products
in the combustion process, which are poisonous to
inhabitants and destructive to
Viessmann equipment.
uFor a listing of chemicals which
cannot be stored in or near the
boiler room, please see subsection
entitled “Combustion Air Supply”.
Advice to owner
Once the installation work is complete, the heating
contractor must familiarize the system operator/
ultimate owner with all equipment, as well as safety
precautions/requirements, shutdown procedure, and
the need for professional service annually before the
heating season begins.
Carbon monoxide
Improper installation, adjustment, service and/or
maintenance can cause flue products to flow into
living space. Flue products contain poisonous carbon
monoxide gas.
uFor information pertaining to the
proper installation, adjustment, service
and maintenance of this equipment to
avoid formation of carbon monoxide,
please see instructions supplied with
burner.
Fresh air
This equipment requires fresh air for
safe operation and must be installed
ensuring provisions for adequate
combustion and ventilation air exist.
uFor information pertaining to the
fresh air requirements of this product,
please see subsection entitled
“Combustion Air Supply”.
Equipment venting
Never operate boiler without an installed venting
system. An improper venting system can cause
carbon monoxide poisoning.
uFor information pertaining to
venting and chimney requirements,
please see section entitled “Venting
Connection”. All products of
combustion must be safely vented
to the outdoors.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Table of Contents
Safety, Installation and Warranty Requirements..............2
Important Regulatory and Installation Requirements........5
About these Installation Instructions..............................6
Applicability. .............................................................7
Product Information.....................................................7
Mechanical Room. .....................................................8
Before Set-up.............................................................9
Minimum Clearances. ................................................10
CombiPLUS Installation Options..................................10
Preparing the Connections..........................................11
Connections overview............................................11
Dimensions overview without bottom piping connections..12
CombiPLUS connections and piping connections.......13
Piping connections for Vitodens 100W, WB1B-26
and -35 (factory supplied).......................................14
Wall Mounting..........................................................15
Boiler and CombiPLUS installation............................15
Boiler mounting bracket and CombiPLUS installation..16
Mounting Vitodens 100-W boiler.............................17
Boiler Connections....................................................17
Flue gas connection................................................17
Proper piping practice.............................................18
Gas connection and piping......................................18
Gas piping pressure test..........................................19
Heating water connections......................................20
Condensate connection...........................................21
Fill siphon with water.............................................21
Safety Connections and Pressure Testing.....................22
Installing safety devices on the boiler.......................22
Low water cut-off..................................................22
Performing pressure test on the boiler......................23
Hot water temperature and system pressure.............23
Preparing the CombiPLUS Connections........................24
CombiPLUS Preparations for all Vitodens.....................25
Additional CombiPLUS Prearations for
Vitodens 100-W, WB1B-26 only.................................26
Mounting the CombiPLUS..........................................27
CombiPLUS Installation Options.................................27
Connecting the CombiPLUS Piping................................28
Connecting the CombiPLUS Wiring..............................29
Accessing the Boiler Controls.....................................30
Preparing the Boiler Power Pump Module...................31
Connecting the CombiPLUS Cables to the
Power Pump Module of the Boiler...............................32
Re-installing Covers...................................................33
Adding PRV and Label...............................................34
Programming............................................................35
Safety
General Information
Dimensions
Connections
Page

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Table of Contents
Installation Examples.................................................36
General.................................................................36
Clearances...........................................................36
Pressure drop of Vitodens 100-W.............................36
Typical system flow rates........................................36
Heating circuit pumps.............................................36
CombiPLUS Built-in Pump.......................................37
System layout 1 to 4..............................................38
Vitodens and CombiPLUS Layout...............................44
Boiler in heating/cooling application..........................47
Boiler with low water cut-off (remote mounted, field supplied)..48
Low-loss header.....................................................49
Venting Connection...................................................50
Electrical Connections................................................50
Rotating the control unit and opening the power/pump module...50
Electrical connections to the power/pump module.....51
Optional operating control - OpenTherm...................51
Closing the power / pump module and reinstalling
the control unit....................................................52
Reinstalling the front panel.....................................52
Necessary Tools.......................................................53
Testing/analysis equipment....................................53
Overview of Controls and Indicators............................53
Control and display elements.................................53
Overview of Boiler Components..................................54
Overview of CombiPLUS Components.........................55
Procedure (Overview)................................................56
Steps.......................................................................57
Troubleshooting Steps...............................................73
Changing Room Temperature......................................73
Diagnosis................................................................74
Sequence of operation and potential faults during
each start-up cycle................................................74
Diagnostics table: Faults with fault display on control unit..75
How to reset faults...............................................76
Boiler Connection....................................................77
Remove front panel...............................................77
Check boiler temperature sensor.............................77
Check outdoor temperature sensor..........................78
Determining the boiler set-point..............................79
Check fixed high limit............................................80
Check flue gas temperature sensor..........................80
Check fuses.........................................................81
CombiPLUS Connection...........................................82
Check outlet temperature sensor.............................82
Replacing the flow limiter.......................................82
Checking or replacing the plate typeheat exchanger..83
Electrical connections to the Terminal Strip for
Accessories.............................................................84
Technical Data........................................................85
Call for heat priority logic table...............................85
Burner Program Sequence of Operation........................89
Wiring Diagram - Natural gas / Propane........................91
Service Function Overview.........................................92
Parts List................................................................93
Maintenance Record..................................................98
Lighting and Operating Instructions.............................99
Connections (continued)
Venting Connections
Control Connections
Start-up, Inspection and Maintenance
Troubleshooting
Additional Information
Page

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Safety
Important Regulatory and Installation Requirements
Codes
The installation of this unit shall be in accordance with
local codes or, in the absence of local codes, use CAN/
CSA-B149.1 or .2 Installation Codes for Gas Burning
Appliances for Canada. For U.S. installations use the
National Fuel Gas Code ANSI Z223.1. Always use latest
editions of codes.
In Canada all electrical wiring is to be done in accordance
with the latest edition of CSA C22.1 Part 1 and/or local
codes. In the U.S. use the National Electrical Code ANSI/
NFPA 70. The heating contractor must also comply with
both the Standard for Controls and Safety Devices for
Automatically Fired Boilers, ANSI/ASME CSD-1, and
the Installation Code for Hydronic Heating Systems,
CSA B214-01, where required by the authority having
jurisdiction.
u Leave all literature at the installation site and advise
the system operator/ultimate owner where the
literature can be found. Contact Viessmann for
additional copies.
u This product comes with several safety instruction
labels attached. Do not remove!
Contact Viessmann immediately if replacement labels
are required.
For installations on the Commonwealth of Massachusetts, the following modifications to NFPA-54 chapter 10 apply:
Excerpt from 248 CMR 5-08:
2(a) For all side-wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used
in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where
the side-wall exhaust vent termination is less than (7) feet above finished grade in the area of the venting,
including but not limited to decks and porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side-wall horizontal
vented gas fueled equipment, the installing plumber or gas fitter shall observe that a hard wired carbon
monoxide detector with an alarm and battery back-up is installed on the floor level where the gas equipment
is to be installed. In addition, the installing plumber or gas fitter shall observe that a battery operated or hard
wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling, building or
structure served by the side-wall horizontal vented gas fueled equipment. It shall be the responsibility of
the property owner to secure the services of qualified licensed professional for the installation of hard-wired
carbon monoxide detectors.
a. In the event that the side-wall horizontally vented gas fueled equipment is installed in a crawl space or an
attic, the hard-wired carbon monoxide detector with alarm and battery back-up may be installed on the next
adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of completion of installation,
the owner shall have a period of thirty (30) days to comply with the above requirements; provided, however,
that during said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall
be installed.
2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in accordance
with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.
3. SIGNAGE. A metal or plastic identification plate shall be permanently mounted to the exterior of the building
at a minimum height of eight (8) feet above grade directly in line with the exhaust vent terminal for
the horizontally vented gas fueled heating appliance or equipment. The sign shall read, in print size no
less than one-half (1/2) inch in size, “GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.
4. INSPECTION. The state or local gas inspector of the side-wall horizontally vented gas fueled equipment shall
not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and
signage installed in accordance with the provisions of 248 CMR 5.08(2)(a) 1 through 4.
(b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a) 1 through 4:
1. The equipment listed in Chapter 10 entitled “Equipment Not Required To Be Vented” in the most current
edition of NFPA 54 as adopted by the Board; and
2. Product Approved side-wall horizontally vented gas fueled equipment installed in a room or structure separate
from the dwelling, building or structure used in whole or in part for residential purposes.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Safety/ General Information
Important Regulatory and Installation Requirements (continued)
Working on the equipment
The installation, adjustment, service, and maintenance of
this boiler must be performed by a licensed professional
heating contractor who is qualified and experienced in the
installation, service, and maintenance of hot water boilers.
There are no user serviceable parts on the boiler, burners,
or control.
Ensure main power supply to equipment, the heating
system, and all external controls has been deactivated.
Close main gas supply valve. Take precautions in all
instances to avoid accidental activation of power during
service work.
Technical literature
Literature for the Vitodens boiler:
- Technical Data Manual
- Installation and Service Instructions
- Operating Instructions and User's Information Manual
- Vitodens Venting System Installation Instructions
- Instructions of other products utilized and installed
- Installation codes mentioned
in this manual and as locally applicable
u The completeness and functionality of field supplied
electrical controls and components must be verified
by the heating contractor. This includes low water
cut-offs, flow switches (if used), staging controls,
pumps, motorized valves, air vents, thermostats, etc.
u Leave all literature at the installation site and advise
the system operator/ultimate owner where the
literature can be found. Contact Viessmann for
additional copies.
u This product comes with several safety instruction
labels attached. Do not remove!
Contact Viessmann immediately if replacement labels
are required.
About these Installation Instructions
Take note of all symbols and notations intended to draw attention to potential hazards or important product
information. These include “WARNING”, “CAUTION”, and “IMPORTANT”. See below.
u
IMPORTANT
CAUTION
uWarnings draw your attention to the presence of
potential hazards or important product information.
uCautions draw your attention to the presence of
potential hazards or important product information.
uHelpful hints for installation, operation or maintenance
which pertain to the product.
uThis symbol indicates that additional, pertinent
information is to be found.
uThis symbol indicates that other instructions must
be referenced.
WARNING
Indicates an imminently hazardous situation which,
if not avoided, could result in death, serious injury
or substantial product/property damage.
Indicates an imminently hazardous situation which,
if not avoided, may result in minor injury or product/
property damage.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service General Information
Applicability
The boiler serial number must be provided when ordering
replacement parts. Both the 16-digit serial number bar
code label and the 12-digit ASME/NB serial number
correlate to each other. Providing either serial number is
sufficient.
Model No. Serial No.
WB1B 26 7457960£££££££££
and
WB1B 35 7457961£££££££££
Product Information
Natural / propane gas-fired wall-mounted hot water heating boiler for space heating.
For operation with constant (set-point) and outdoor temperature responsive control in closed loop, forced circulation
hot water heating circuits. An external controller is required for indirect storage tank DHW production (an optional
CombiPLUS kit providing reliable on demand hot water without a DHW tank is available).
The Vitodens 100-W comes factory set for operation with natural gas. Propane conversion kit is included with each boiler.
Boiler model must be selected based on an accurate heat loss calculation of the building. Ensure boiler model is
compatible with connected radiation.
Vitodens 100-W boilers are factory tested and calibrated. Further gas valve adjustments are typically not required
during field start-up.
Follow the Vitodens Venting System Installation Instructions to vent this boiler.
ASME/NB stamp 12-digit
serial number location
(metallic plate riveted on
the heat exchanger) H
Stainless steel Inox-Radial
heat exchanger
IMPORTANT
Serial No. location (16-digit
bar code white label located
on the boiler as shown in
this drawing)
Note: Check the boiler rating plate on the Vitodens 100-W,
models WB1B-26 or WB1B-35 to ensure it states
compatibility with the CombiPLUS kit.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Mechanical Room
General Information
During the early stages of new home design, we
recommend that proper consideration be given to
constructing a separate mechanical room dedicated to
gas- or oil-fired equipment including domestic hot water
storage tanks.
The boiler must be located in a heated indoor space,
near a floor drain, and as close as possible to the wall.
Whenever possible, install boiler near an outside wall so
that it is easy to duct the venting system to the boiler.
Locate boiler on walls capable of supporting the weight
of the boiler filled with water (see section entitled
“Technical Data" on page 86 for information required for
total boiler weight calculation). Ensure that boiler location
does not interfere with proper circulation of combustion
and ventilation air of other fuel burning equipment (if
applicable) within the mechanical room.
The maximum room temperature of the mechanical room
where the boiler is located must not exceed 104° F (40° C).
Boiler operation in marine environments (damp, salty
coastal areas):
The service life of the boiler’s exposed metallic surfaces,
such as the casing and fan housing, is directly influenced
by proximity to damp and salty marine environments. In
such areas, higher concentration levels of chlorides from
sea spray, coupled with relative humidity, can lead to
degradation of the exposed metallic surfaces mentioned
above. Therefore, it is imperative that boilers installed
in such environments not be installed using direct vent
systems which draw outdoor air for combustion. Such
boilers must be installed using room air dependent vent
systems; i.e. using room air for combustion. The indoor
air will have a much lower relative humidity and, hence,
potential corrosion will be minimized.
IMPORTANT
WARNING
If you notice fire coming from the appliance, call the
fire department immediately! Do not attempt to
extinguish the fire unless qualified to do so.
WARNING
Fire causes a risk of burns and explosion!
nShut down the boiler
nClose fuel shut-off valves
nUse a tested fire extinguisher, class ABC.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Installation area conditions
gEnsure ambient temperatures are higher than 32° F
(0° C) and lower than 104° F (40° C).
gPrevent the air from becoming contaminated by
halogenated hydrocarbons (e.g. as contained in
paint solvents or cleaning fluids) and excessive dust
(e.g. through grinding or polishing work).
Combustion air for the heating process, and ventilation
of the boiler room must be free of corrosive
contaminants. To that end, any boiler must be installed
in an area that has no chemical exposure. The list to
the right indicates the main, currently known sources.
gAvoid continuously high levels of humidity
(e.g. through frequent drying of laundry).
gNever close existing ventilation openings.
WARNING
Incorrect ambient conditions can lead to damage to
the heating system and put safe operation at risk.
Mechanical Room (continued)
Sources of combustion and ventilation air contaminants.
Areas likely to contain contaminants:
- New building construction
- Swimming pools
- Remodelling areas, hobby rooms
- Garages with workshops
- Furniture refinishing areas
- Dry cleaning/laundry areas and establishments
- Auto body shops
- Refrigeration repair shops
- Metal fabrication plants
- Plastic manufacturing plants
- Photo processing plants
- Beauty salons
Products containing contaminants:
- Chlorine-type bleaches, detergents and cleaning
solvents found in household laundry rooms
- Paint and varnish removers
- Hydrochloric acid, muriatic acid
- Chlorine-based swimming pool chemicals
- Spray cans containing chlorofluorocarbons
- Chlorinated waxes and cleaners
- Cements and glues
- Refrigerant leaks
- Calcium chloride used for thawing
- Sodium chloride used for water softening salt
- Permanent wave solutions
- Adhesives used to fasten building products and other
similar items
- Antistatic fabric softeners used in clothes dryers
Before Set-up
Before placing boiler in its installation location, ensure all
necessary accessories are installed. CAUTION
The boiler must be installed in such a way that gas ignition
system components are protected from water (spraying,
splashing, etc.) during boiler operation and service.
General Information

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Minimum Clearances
Recommended minimum service clearances
Note:The Vitodens 100-W boiler has passed the zero
inches vent clearance to combustibles testing
requirements dictated by the boiler Harmonized
Standard ANSI Z21.13. CSA 4.9.2007 and
therefore is listed for zero clearance to combustibles
when vented with a single-wall special venting
system (AL-29-4C material) or UL/ULC-listed CPVC
gas vent material. The zero inches vent clearance
to combustibles for the Vitodens 100-W boiler
supercedes the clearance to combustibles listing
that appears on the special venting system label.
Top clearance - 12” (30 cm).
See the Vitodens Venting System
Installation Instructions.
Clearance to combustibles
AL = Alcove
CL = Closet
Top Front Rear Left Right Vent
pipe*1
0 0 AL,
CL
0 0 0 0
Front
Side
Side
Back
Top *
7”/178mm
5
*1Refer to the Installation Instructions of the Vitodens
Venting System for details.
CombiPLUS Installation Options
Shown is the distance between the boiler and CombiPLUS
with Viessmann supplied 7” flex piping connection fittings.
Shown is the maximum distance between the boiler
and CombiPLUS using field supplied fittings and pipes.
Note: The maximum distance between
the boiler and the CombiPLUS
is restricted by the communication
cable to 36” (915 mm).
Dimensions

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Preparing the Connections
Connections overview
Note: Use an approved pipe sealant or teflon tape when
connecting the following installation fittings.
This section is an overview only!
Refer to subsequent sections for detailed information on
individual piping connections.
Piping connections for Vitodens 100-W, WB1B 26 and 35
(factory supplied)
Legend
BWR Boiler water return, ¾”
BWS Boiler water supply, ¾”
BD Boiler drain
BF Boiler fill
GC Gas connection, ¾” NPTM (male thread)
PRV Pressure relief valve
NPT National Pipe Thread
VC Vent connection
CAI Combustion air inlet connection (optional)
Dimensions

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Preparing the Connections (continued)
Dimensions overview without bottom piping connections
Connections Vitodens 100-W, WB1B 26, 35
Legend
Connections
ACondensate drain, plastic hose Ø 0.87” (22 mm)
BBoiler water supply, NPT ¾” (male thread)
CGas connection, NPT ¾” (male thread)
DBoiler water return, NPT ¾” (male thread)
ECombustion air opening for double pipe system
FCombustion air opening for coaxial system
Dimensions
a 14” (355 mm)
b 15¾” (400 mm)
c 2f” (68 mm)
d 28½” (725 mm)
e 47/8” (123 mm)
f 6d” (156 mm)
g 14d” (360 mm)
h 5” (125 mm)
j 97/8” (250 mm)
k 1a” (31 mm)
m 77/8” (200 mm)
n 3d” (80 mm)
The maximum ambient temperature must not exceed
104º F (40º C).
gHeating water connections and gas connection to be
made in the field. See connection-specific section for
details.
gSee subsection entitled “Power supply connection"
for details regarding power supply to the Vitodens
100-W boiler.
IMPORTANT
When preparing gas, water and electrical
connections in the field, see section entitled
“Wall Mounting” on page 15 of this manual for
information regarding the installation of the wall
mounting bracket.
Front view Side view Top view
Dimensions

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Dimensions
Preparing the Connections (continued)
CombiPLUS connections and piping connections
Top view
Side view
Front view
A B
C DE F
Front view
Legend
ABoiler water supply, NPTM ¾” (male thread)
BBoiler water return, NPTM ¾” (male thread)
CSystem water supply, NPTM ¾” (male thread)
DSystem water return, NPTM ¾” (male thread)
EDHW, NPTM ½” (male thread)
FDCW, NPTM ½” (male thread) Shown is the distance between the boiler and CombiPLUS
with Viessmann supplied 7” flex piping connection
fittings.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Dimensions
Preparing the Connections (continued)
Legend
BWR Boiler water return, ¾”
BWS Boiler water supply, ¾”
BD Boiler drain
BF Boiler fill
GC Gas connection, ¾” NPTM (male thread)
PRV Pressure relief valve
PG Pressure gage
VC Venting connection
CAI Combustion air inlet connection (optional)
This section is an overview only! Refer to subsequent sections for detailed information on individual piping connections.
Piping connections for Vitodens 100-W, WB1B 26 and 35 (factory supplied)
Note: If using the optional CombiPLUS see page 10 and 24.

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Dimensions
Wall Mounting
Boiler and CombiPLUS installation
The Vitodens 100-W boiler and CombiPLUScan be
wall-mounted on:
- a brick/concrete wall
- wood studs
- metal studs
Following are the installation instructions for the mounting
bracket on each material. Skip to the installation
instructions applicable to your installation requirements.
Installation of mounting bracket on brick/concrete wall:
1. Drill holes [Ø e”(10 mm)], using mounting templates
supplied with the boiler and the CombiPLUS.
2. Align wall mounting boiler bracket and attach to wall
with the screws and plastic anchors supplied. The
CombiPLUS is mounted directly to the wall with the
screws and plastic anchors supplied.
CAUTION
Whichever mounting method is used, ensure that the
boiler bracket and CombiPLUS is tightly and securely
fastened to wall. Failure to secure boiler or CombiPLUS
properly could cause loosening, posing a severe safety
hazard.
1.
1.
2.
mm
2.
1.
mm
Legend
AMounting template
BCombiPLUS mounting template

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Dimensions
Wall Mounting (continued)
Install mounting bracket and CombiPLUS on wood studs
as per illustration. Drill 3/16” pilot holes to insert mounting
bolts. Ensure that holes are located in the center of each
wood stud. Secure with bolts to wooden studs as shown.
Install mounting bracket and CombiPLUS on metal studs
as per illustration. Drill f” pilot holes to insert anchors.
Ensure that holes are located in the center of each metal
stud. Use appropriate fasteners to mount CombiPLUS to
metal studs (not supplied). Secure with bolts to metal
studs as shown.
Boiler mounting bracket and CombiPLUS installation
Installation on wood studs
Boiler bracket
CombiPLUS
Boiler bracket
CombiPLUS
Installation on metal studs

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Dimensions/Connections
Wall Mounting (continued)
Mounting Vitodens 100-W boiler
Boiler Connections
Flue gas connection
Note: Prior to installing the boiler, if a CombiPLUS kit
is also required, verify that the minimum mounting
clearances are met.
1. Loosen the screws at the bottom of the boiler; do not
remove completely.
2. Remove the front panel.
3. Mount boiler onto the mounting bracket.
For installation of the mounting bracket, see
subsection entitled “Wall mounting installation”
on page 16 of this manual.
The Vitodens 100-W boiler comes with a preinstalled vent
pipe adaptor (as shown).
Run venting system, single-pipe, double-pipe or coaxial,
through the side wall, roof or chimney, taking the shortest
possible route and at a rising angle (min. 3º).
Installation Instructions Vitodens Venting System.
For double pipe installation, the combustion
air inlet cover Cmust be in place. Also refer
to the Venting Manual.
Remove and discard combustion air
inlet cover Cwhen installing coaxial
vent pipe system.

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Vitodens 100-W, WB1B Installation & Service
Connections
Boiler Connections (continued)
Proper piping practice
Gas connection and piping
Support piping by proper suspension method.
Piping must not rest on or be supported by boiler.
Legend
AWater supply connection
BCondensate drain connection
CGas connection
DWater return connection
1. Make gas connection in accordance with codes
CAN/CSA B149.1 or 2 in Canada. In the United
States, use the National Fuel Gas Code ANSI Z223.1/
NFPA 54, as well as local codes where applicable.
2. Close gas shutoff valve on boiler.
3. Perform leak test.
4. Bleed air from gas supply pipe.
See following page for details on gas connection and piping.
2 imperfect threads Use moderate amount of dope
Leave 2 threads bare

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5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service Connections
Boiler Connections (continued)
Gas connection and piping (continued)
Legend
AGas connection
BAccessible manual gas
shutoff (factory supplied)
CDrip leg
Max. gas supply pressure: 14 “w.c.
1. Refer to current CAN/CSA B149.1 or 2 in Canada.
In the United States, use the National Fuel Gas Code
ANSI Z223.1/NFPA 54, as well as local codes for gas
piping requirements and sizing. Pipe size to the boiler
must be determined based on:
- pipe length
- number of fittings
- maximum input requirements of all gas appliances in
the residence.
Design piping layout in such a way that piping does not
interfere with serviceable components.
2. Before connecting boiler to gas line, install ground
joint union, capped drip leg and a manual equipment
shutoff valve. Valves must be listed by a nationally
recognized testing agency. Make boiler gas
connection as shown on the left.
Gas connection (NPT)..........∅¾”
3. Perform gas piping pressure test as described in the
following subsection.
4. Identify shutoff valves as such with a tab and
familiarize operator / ultimate owner of boiler with
these valves.
CAUTION
WARNING
The gas supply piping must be leak tested before
placing the boiler in operation.
Ensure that gas piping is large enough for all appliances
in the residence. No noticeable gas pressure drop in the
gas line must occur when any unit (or combination of
units) lights or runs.
IMPORTANT
IMPORTANT
Gas piping pressure test
½ psig = 14 “w.c.
1. Isolate the boiler from the gas supply piping system
using the individual manual shutoff valve during
pressure tests equal to or less than ½ psig (14 “w.c.)
2. The boiler and its individual shutoff valve must be
disconnected from the gas supply piping system
during any pressure testing of that system at test
pressures in excess of ½ psig (14 “w.c.)
3. Perform leak test. Use approved liquid spray solution
for bubble test. Ensure that no liquid is sprayed on
any electrical components, wires or connectors. Do
not allow leak detection fluid to contact gas valve
regulator or regulator vent opening.
4. Correct any and all deficiencies.
5. Remove air from gas line.
When performing the gas piping pressure test, ensure the
following requirements are met.
WARNING
Never check for gas leaks with an open flame.
WARNING
Exposing boiler gas pressure regulator and gas valve to
extreme pressures renders warranty null and void.
IMPORTANT

20
5600 332 v1.3
Vitodens 100-W, WB1B Installation & Service
Boiler Connections (continued)
Connections
Heating water connections
Legend
BWR Boiler water return, ¾”
BWS Boiler water supply, ¾”
BD Boiler drain
BF Boiler fill
GC Gas connection, ¾” NPTM
PRV Pressure relief valve
NPT National Pipe Thread
PG Pressure gage
1. Thoroughly flush heating system (particularly before
connecting the boiler to an existing system).
2. Connect boiler to the heating system.
Max. operating pressure.......................3 bar (45 psig)
Test pressure......................................4 bar (60 psig)
Damage resulting from pressure exceeding those values
stated is not covered by Viessmann warranty.
gUse a two-hand wrench method when tightening
fittings or piping onto the boiler connectors. Use
one wrench to prevent the boiler pipes from twisting
and the second wrench to tighten the fitting or
piping. Failure to support the boiler connection could
damage the boiler and its internal piping.
SUPPORT ALL PIPING USING HANGERS. DO NOT support
piping by the unit or its components.
gUse isolation valves to isolate system components.
gAll plumbing must meet or exceed all local state and
national plumbing codes.
WARNING
The pressure gage is a sensitive component and may
be damaged if the boiler connections are not supported
by using a second wrench when tightening fittings
and/or piping.
IMPORTANT
IMPORTANT